CN117500989A

CN117500989A - V-connection for concrete member cross-joint and shear key

Info

Publication number: CN117500989A
Application number: CN202080105093.8A
Authority: CN
Inventors: 郝苏; A·J·郝
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-07-12
Filing date: 2020-07-19
Publication date: 2024-02-02
Also published as: WO2022013587A1

Abstract

The invention discloses a device for cross-connecting and reinforcing connection of multi-directional structural members, which is characterized by a combination of designed details, including V-shaped cavities, pins or reinforcing bars penetrating the cavities, and additional V-shaped reinforcing sleeves and shear keys. The key innovation is to eliminate high stress concentration in local areas through design details including asymptotic contact, and to design a pull-up mechanism to maintain structural integrity by utilizing structural prestress and self-gravity under extreme loading conditions when the structural function is lost.

Description

V-connection for concrete member cross-joint and shear key

Applicant-related patent invention or patent invention application

PCT/US2012/063127 PCT/US2016/013741 PCT/US2018/013205

US62,163,258 US14,986,725 US13,163,724

Other inventions or invention applications:

US1,647,925 US2,645,090 US2,950,517

US3387417A US3,703,748 US3,899,891

US3,794,433 US6,021,992 US 6,560,939B2

JP2008050820A JP2011001717A CN201310051667

RU185 762U1 US 9,926,698 B2 CN105804241A

PCT/KR2004/001539 PCT/KR2006/004958

other documents

[1]Hao,S.,Report of NCHRP(National Cooperation Highway Research Program)188

[2] Hao, S. (Hao Su), "Retrofit/Replacement for Free Bridge Road over Running Reelfoot Bayon and Discussion of the SVC Application ofSTD6-1 Seismic Detailing for SDC D Bridge", presentation at the Structural Division, tennessee Department of Transportation, US, sept.5,2019

[3]Federal Highway Administration(FHWA):Post-Tensioning Tendon Installation and Grouting Manual,2013

[4] JTG 3362-2018, "reinforced concrete and prestressed concrete bridge and culvert design Specification for highway

[5]Federal Highway Administration(FHWA):Post-Tensioning Tendon Installation and Grouting Manual,2013

[6]ASCE/SEI,"Minimum Design Loads for Buildings and Other Structures",1995-2016versions.

[7]"LRFD Bridge Design Specifications",AASHTO,the 1st(1994)to the 7th Editions(2016)

[8]AASHTO"Guide Specifications for Seismic Bridges'Design",,1st Ed.,Second Edition,2011

[9]Amendment to AASHTO LRFD Bridge Design Specification-4th Ed.,Section 14:Joints and Bearings,Caltran,2010.

[10]Post-Tension Institute(PTI)Publication:"Anchorage Zone Design,"Post-Tensioning Institute,First Edition,October,2000.

[11]Post-Tension Institute(PTI)Publication:"Post-Tensioning Manual,"Sixth Edition,2006.

[12]American Segmental Bridge Institute(ASBI)Publication:"Construction Practices Handbook for Concrete Segmental and Cable-Supported Bridge"Third Edition,2019.

[13]Touaillon J.,"Improvement in Buildings",United States Patents Office,Letters Patent No.99.973,February 15,1870.

[14]"Experimental Investigation on the Seismic Response of Bridge Bearings",Univ.of California,Berkeley,EERC-2008-02,2008.

[15]Kelly,J.M.,1997,"Earthquake-resistant design with rubber",2nd Ed.,Springer,London.[16]"Rotation Limits for Elastomeric Bearings",Report 12-68,University of Washington,2006

[17]Hao,S.,"Retrofit/Replacement for Free Bridge Road over Running Reelfoot Bayon and Discussion of the SVC Application of STD6-1 Seismic Detailing for SDC D Bridge",Presentation at the Structural Division,Tennessee Department of Transportation,US,Sept.5,2019

[18]Hao,S.,"V-connection against Bridge's Deck Overturn",Presentation at the Chinese National Bridge Annual Conference,Nov.15th,2019

[19]Hao,S.,"V-connector to Protect Bridges from Earthquake Damage and Deck's Overturn",Presentation at the Chinese Bridge Magazine Annual Road Showing:Dec.7th,2019

Technical Field

The present invention discloses a class of design details for connection methods for constructing components of large civil engineering structures (e.g., bridges and buildings) made primarily of concrete elements or a combination of concrete and steel elements. Concrete is a practical building material and is characterized by high compressive capacity but lacking in tensile strength. One common method of reducing tensile stress in a curved concrete member, such as a beam or column, is the "prestressing" technique which uses tendons or rods to apply compressive forces on both ends of the member before it begins to be used, which will maintain its concrete matrix in a compressed condition to counteract the tensile stress caused by the load actually applied during use, see figure 1.

Obviously, the conventional prestressing method in this figure is only applicable to members whose geometry is much larger in one direction than the other two orthogonal directions, for example, curved members, whose tensile stress peaks appear in the length direction when they are subjected to bending moments caused by external loads. However, when multiple curved members meet at a crossover joint along one, two, or three paths, how to apply the prestressing remains a challenge for the construction industry; fig. 2 (a) is an example of connection of a bridge center sill and a column, and fig. 2 (b) is an example of connection of three-way cross piers in a building. On the other hand, for horizontally aligned structural members, such as prefabricated segment bridges, the weight of the structure is transferred substantially to the shear force on the contact surface pairs between the two connecting segments. To maintain this shear force, two common methods are grouting through epoxy or dry joints with additional concrete shear keys. However, grouting is a time consuming process that may offset the benefits of the prefabricated segment components in accelerating construction, and the shear capacity of concrete shear keys is limited, while ensuring good installation of the shear keys on the contact surface remains another challenge.

In general, the strength of structural cross joints is critical to large civil engineering works from the standpoint of structural integrity and safety. This is because, obviously, failure of such a joint will result in failure of all relevant components. Since the stress levels at the intersections are typically higher than in other parts, the robustness and strength of such locations substantially determine the load carrying capacity of the structure, especially under extreme loading conditions such as hurricanes, strong shocks, collisions between bridges and barges or vehicles, and explosions.

Another common construction engineering method is the "cast-in-place" (CIP) method, i.e., pre-arranging a rebar grid within a structural prefabrication formwork; the liquefied concrete mixture is then poured and the tension and shear forces are resisted by the rebar grid embedded in the concrete matrix. However, by this process, the curing and necessary ageing of the cast-in-place concrete takes at least 28 days; the cost of building a form for casting is about 20% to 60% of the construction extra budget.

In contrast, when the main components of the structure can be manufactured at the factory, i.e. beams and columns are manufactured at the factory, prefabricated and prestressed, then these components are assembled on site, the construction process will be significantly reduced and significant economic benefits will be brought about. This modular structure highlights the decisive role of connecting the prefabricated component joints in the load-bearing capacity and the robustness of the structure. To this end, the invention discloses a device and a method of connection with innovative design details for reinforcing the cross joints of structural components and increasing the load carrying capacity perpendicular to the normal prestressing direction, realizing a modular structure.

Background

One long-standing challenge faced by the civil engineering community is how to achieve rapid construction while ensuring structural integrity and durability. In densely populated areas, a bridge may take a long time to build, and traffic jam is often caused, which not only brings inconvenience to the public driving, but also causes indirect economic loss due to time loss caused by traffic delay. On the other hand, natural disasters with devastating consequences, such as strong earthquakes over the past decades, alert our nature to the continued threat to human life, especially in the united states and other areas of the world where the risk of earthquakes is high. Needless to say, the method includes: techniques and methods to accelerate construction are of course desirable or necessary, but the integrity and robustness of the precondition must be able to guarantee public safety. The present invention is directed to achieving this goal.

Most large civil engineering structures are built from structural concrete or composite concrete-steel composites. To avoid the disadvantage of lack of tensile strength in concrete, prestressing is a commonly used technique. However, as previously mentioned, this technique is generally applicable to elongate members such as beams and columns. The cross-joints of concrete structures are often in complex stress states, possibly the weakest link of such structures. An extreme example is the unfortunate collapse event of a pedestrian overpass at the campus of the international university florida, month 3 of 2018. However, as reviewed in the "literature review" section below, this is the focus of widespread attention so far. A class of engineering solutions is proposed in the art to enhance earthquake resistance and modular construction capacity by multidirectional prestressing of the connection between structural members, in particular the cross-joints of concrete members or the combination of concrete and steel members.

Summary of past invention literature

Large concrete or steel-concrete composite structures, i.e. bridges and buildings, essentially comprise four main structural members: horizontal curved members (e.g., beams and roof shells), vertical curved members (e.g., columns), foundation members (e.g., footings), and cross-joints connecting these members. The prestressing of the flexing member as shown in fig. 1 is a common engineering practice today. Continued effort and related inventions can be seen with respect to post-tensioning of the assembled blocks and footings.

In 1953, patent US2645090 describes a method of casting a monolithic or segmented concrete pile with a longitudinally extending central bore, in which a pre-stressed steel cable is passed through the joints at both ends, whereby the cable is placed in tension and the pile is placed in compression, as shown in figure 3 (a). This concept is extended in US389891, where the pile is an assembly of a plurality of vertically arranged tubular drive housing parts, which are connected one after the other by means of penetrating tendons; the rebar end anchoring technique is described in US3703748, fig. 3 (b). In contrast, US1647925, fig. 4 (a), discloses the invention using steel socket anchor rods at footings and nuts to secure the rods to the pile heads. Chinese application CN110685215a describes the assembly of a plurality of pile segments and footings with through-reinforcing steel segments; the steel bushings are used to connect the steel bars of adjacent pile segments directly above their contact faces as shown in fig. 4 (b). Similar to the embodiment of fig. 4 (b), tendons pass through the pile section, adding cavities at the interface, top post-tensioning as shown in fig. 4 (c) CN109610304 a. With regard to the technical details of the coupler connecting the cable and the rebar, US 6560939B2 describes an intermediate anchoring system that is connected to two tendon ends that are not aligned on the same axis. Fig. 5 (a). PCT/KR2006/004958, a threaded connection of two rods with threaded ends is described in detail in FIG. 5 (b). A structural assembly is introduced in US6742211 in which a stake having a concave bottom surface is dropped onto another stake having a convex top surface to increase resistance to lateral displacement, fig. 6. Each pile block has a cylindrical opening in its convex upper surface and is filled with concrete grout around it by passing through tendons. Fig. 7 shows the wet joint between two spans and one pier in US3794433, which does provide a revolutionary improvement in the construction of post-tensioned concrete bridges. Fig. 8 is a cross-over joint of two rear Zhang Daoguan and saddle anchors in US2950517 1960, which is part of a cross-laid rebar grid embedded in the plane of a road deck. JP2011001717a uses sets of side bolts (called "temporary brackets") to position the posts on the bi-directional plate cross joint to connect the rebar extending from the bottom of the posts with the rebar extending from the plate cross joint surface by means of "couplers"; a form containing these couplers is then made for casting concrete, as shown in fig. 9. Although the struts are prefabricated and may be pre-stressed, no back tension is applied to the joint during operation.

Although [5] provides a general guide line for post-tensioning of concrete bridges, the U.S. department of transportation in tennessee (TDOT) has been in daily engineering practice for decades to pre-stress wet joints between two spans at the tops of piers to prevent earthquakes. The corresponding procedure is as follows: the bolt is first cast as a post and protrudes at its top; then placing the ends of the two spans on the tops of the two sides of the bolt; the concrete mixture is then poured into the gap between the two span ends while tightening the bolt tops to apply pressure to a portion of the wet joint. Fig. 10 (a) and 10 (b) are two standard designs showing two support pads of a wet crossover joint to provide some lateral sliding capability. First, an elastic pad is placed between the bottom of the joint and the top of the pier, and an asphalt fiberboard is laid as a load bearing pad. However, such designs do not take into account the load-bearing capacity of the anchor bolt in terms of shear strength when lateral sliding occurs. Fig. 10 (c) is an example of a rebar grid layout within a wet joint.

The prior art with top fastening is JP200 8050820a, fig. 11, for two structural blocks connected vertically by through bolts; wherein the lower end of the bolt is anchored in the lower block and the upper end thereof is fastened on top of the upper block. Instead of the elastomer or asphalt fiberboard in fig. 10, the V-shaped interface between the two blocks is designed to allow relative horizontal sliding; to accommodate this movement, the diameter of the bore in the upper cylinder through the rod is much larger than the diameter of the rod; a thick cushion washer is provided between the nut and the top surface of the upper block.

As shown in fig. 1, the back tension provides compressive force in the longitudinal direction through the tendon, and thus a practical problem is how to increase the resistance of such a structure to shear in a plane intersecting the back tension direction. Taking bridge piers as an example, extreme loading conditions such as earthquakes, hurricanes, vehicle collisions, and explosions are often characterized by extremely high lateral forces. The rod-fastened crossover joint design in fig. 10 and 11 means that the transverse forces will shear the rod or bolt fixed in that position, as shown in the left-hand diagram of fig. 11, given that when the bridge is subjected to a strong seismic impact, relative transverse sliding is allowed to reduce the transverse inertial forces, but the design details of both do provide enough consideration to sustain such movement. The vertical extreme load also introduces extremely high combined tension and shear forces on the post-tensioned tendons or rods; these loads can occur when a tsunami strikes a bridge, or a bridge near the middle of an earthquake, or an overweight vehicle on the deck side.

In order to introduce proper vibration energy dissipation mechanism and ensure the reliability of structural member connection, international intellectual property priority PCT/US2016/013741 discloses a connection mode of combination of anti-seismic connecting pins and V-shaped openings, which is mainly used for connecting pier beams of a structure and connecting piers with a foundation; as shown in fig. 12. The anti-seismic pins have stronger side shearing resistance; to further relieve its stress concentration near the contact surface of the two connecting structural members, this document discloses an anti-seismic pin design with locally increased diameter and an additional shear reinforcement ring, as shown in fig. 13. Such devices are focused on shock resistance and may be used for the joining of steel or concrete components, rather than prestressing. As a continuing innovation of the shock resistant connection pin and V-shaped opening combination, two design details of the fixed end pin and the hinge end pin are disclosed in PCT/US2018/013205, see fig. 14.

Fig. 15 is a type of bridge or building seismic isolation apparatus disclosed in U.S. patent No. 6021992, also known as a friction pendulum sliding support (FPS). Inventions based on the principle of equivalent pendulum also include tens of other U.S. and other national/regional patents which utilize the gravity of the loaded superstructure to cause a horizontal component on the camber to resist the horizontal inertia caused by ground movement. The disadvantage of this device is that it is unconstrained in the vertical separation of the connecting structure, and requires a larger base, resulting in a larger pier diameter and foundation; according to the california highway office experience in the united states, the use of friction pendulum will increase bridge budget by 25% to 125%. In contrast, PCT/US 2012/0631127 discloses an invention that utilizes the horizontal consequences of the weight of the superstructure carried on a V-shaped sliding surface to resist seismic induced lateral motion. For this purpose, horizontal sliding pins and vertical stiffening pins (known in the art as fasteners) are compatible with the horizontal displacement of the relative sliding, respectively, to resist horizontal inertial forces with the horizontal component of the upper structure gravity force on the ramp while limiting the vertical separation between the connected upper and lower structures, see fig. 16.

The technology disclosed by the invention focuses on the earthquake resistance of a prestressed concrete structure connecting system; meanwhile, the bridge anti-overturning device also has the function of bridge anti-overturning according to the similarity of load and structural response.

Disclosure of Invention

As described in the previous section, the conventional construction method uses post-tensile stress to pre-stress compression in one direction in the structural member to balance the peak of tensile stress caused by the work load, however, when the peak stress is not parallel to the rear Zhang Fangxiang (e.g., the intersection joint between a plurality of concrete members), it does not always provide sufficient ability to resist the deformation and the generation of the deformation in the other direction, nor can it improve the adverse stress state at the position having the complex geometry. Extreme loading conditions, such as severe earthquakes, can result in horizontal forces and corresponding structural deformations that may be perpendicular to the post-tensioning direction of the column, and also perpendicular to the post-tensioning of the segmented deck. In order to solve these engineering problems, the object of the present invention is summarized as follows:

(a) A novel class of design details and associated innovative means for establishing and reinforcing structural joints that enable post-tensioning in multiple directions, particularly for joining concrete members or cross joints of a combination of concrete and steel members.

(b) The disclosed invention is directed to the following aspects: (i) Increasing the ability to withstand strong impacts in directions different from those handled by conventional methods; (ii) The ability to restore the original configuration after time distortion due to extreme external effects; (iii) The installation of the structure and the joint positioning of the auxiliary components are facilitated; (iv) realizing a modular structure; (v) simple and economical.

In the following statements and text, "unit" refers to a "block" or "part" or "member" that is subjected to a prevailing force flow in a civil engineering construction, such as a span beam or column in a bridge or building; and design details refer to all relevant parts and components in the relevant apparatus or device, which parts and components may comprise the units described above, to achieve the above-mentioned object. However, hereinafter "component" refers to a component or assembly of devices.

According to engineering practice, "wet joints" refer to the intersection joints of curved structural members (e.g., beams and a column) joined by in-situ concrete; while "dry seam" is a prefabricated piece of seam that is placed in a designated location to join the components to be joined. As described in the previous section, few techniques have been disclosed due to positioning difficulties.

Connecting two units can be managed by pulling one end of an insertion rod, the other end of which is fixed to one unit, thereby exerting pressure on the contact surface between the units; for example, the beams in fig. 1 may be two short beams that are connected together end-to-end by a back tension, so the robustness of the connection depends on the friction on the contact surfaces. While higher compression may introduce increased friction on the contact surfaces, such increases are limited by the strength limits of the post-tensioned rebar. When extremely high loads (e.g., earthquakes) strike the structure, resulting in forces perpendicular to the back tension, the small relative sliding of the contact faces can result in high shear stress concentrations at the interface, as shown in the leftmost plot of fig. 13; the combined peak stress of shear and post-stretch in the rebar may immediately sever the rebar.

The central idea of an embodiment of the invention is thus to reduce the concentration of shear stresses, locally strengthen the reinforcement and utilize the inherent structural properties, such as weight and back tension of the original design, to accomplish both tasks without changing the overall structure, which also improves the stress conditions at the intersection with back tension in multiple directions.

Three basic conceptual diagrams are given in fig. 17, with emphasis on reducing shear concentration, which adopts a wet joint construction example on a bridge pier proposed by the present inventors, and post-tensioning is performed in the vertical direction by pins; the key example is the combination of V-shaped cavities 3 with pins 1 or 2, into which various methods of anchoring the pins to the pier have been introduced. The V-shaped cavity (hereinafter referred to as V-cavity) is a tapered cavity having an opening at the contact surface between the pier top and the wet joint bottom, wherein the diameter, depth of the opening and curvature of the V-shaped pit are designed according to the preferred function to be disclosed. The underlying innovative mechanisms of these embodiments are explained as follows:

when a strong earthquake strikes the structure in fig. 17, relative sliding between the wet joints and piers is allowed, because (i) only very strong pins or tendons can prevent sliding due to strong earthquake shocks, which may lead to a practically infeasible design; (ii) limited slip has a shock-insulating effect. The V-cavity thus provides a cushioning space for the pin to flex under such load conditions to avoid immediate shear failure.

The curvature of the V-cavity geometry is designed to match the curved configuration of the pin to introduce an asymptotic contact between the pin and the V-cavity surface when a lateral load Q is applied, see fig. 18 (a), where the curved profile of the V-cavity (represented in the figure by the function Y (x)) can be estimated by the following analytical form:

where x, L is the pin coordinate and span length in the V-cavity, i.e., the V-cavity depth; i is the moment of inertia of the pin, E is the Young's modulus of elasticity of the pin material; k1 and k2 are coefficients having values between unity and two.

The asymptotic contact further introduces a pulling-up motion of the upper block when the upper block moves laterally and the lateral displacement reaches a design limit. FIG. 18 (b) illustrates the mechanism of engaging the weight of the connection block against lateral movement, wherein after the deformed pin contacts the side of the V-cavity, the corresponding lateral force Q can be divided into a resultant force perpendicular to the curved pin surfaceResultant force tangential to the surface +.>In the latter case,/->The pulling-up movement of the upper block is introduced, its weight acting as a reaction to the lateral movement and limiting the relative sliding to a specified tolerance.

From FIG. 18 (b), it can be seen that tangential forceIs determined by the angle β by:

wherein, according to the curves in fig. 18 (b) and (eq.1):

Wherein the symbol max _x [f(x)]Refers to taking the maximum of the function f (x) on the x-coordinate.

In practical engineering applications, an earthquake can produce significant high levels of force Q6-9 on the structure. According to a displacement-based seismic design, the time sliding between a pair of connected primary structural units, such as shown in FIG. 2, would be beneficial to maintain structural integrity due to the aforementioned seismic effects. In particular, the time sliding motion will result in (i) dissipation of vibrational energy; (ii) reducing the structural rigidity of the corresponding inertial force; (iii) altering the natural frequency of the structure to avoid resonance.

However, equation 1 applies only to cantilever beams having a fixed length L. As shown in fig. 17, the pin within the V-cavity may deform in three different ways: (i) When the pit opening is too narrow, the pin will first contact the opening edge, the shear stress on the pin being similar to that shown on the left side of fig. 13; (ii) When the contour of the pit exactly matches the curve predicted by equation 1 under load Q1, the pin will fully contact the pit surface in a sudden manner when the transverse force Q reaches the Q1 value; as Q continues to increase, highly localized shear forces may occur; (iii) As Q increases, the pin progressively contacts the V-shaped recess, in other words the contact area between the V-cavity and the pin progressively increases, the pin still deforms like a cantilever, but the span length "L/2-x" progressively decreases, where x increases, resulting in an increase in resistance against further bending, as shown in fig. 18 (c). This mechanism provides better performance and is therefore used for the disclosed design details. In order to find the solution of the asymptotic contact curve, in [1], the V-cavity annular profile is denoted by f (x), and the following first ordinary differential equation is derived from the model in FIG. 18 (c)

And the following two penalty functions ensure that the pin remains in an elastic state:

where λ (x) is the radius of the pin, I (λ (x)) is the cross-sectional bending moment of the pin, which may vary; f (Q, L/2-x, λ (x)) is the pin end deflection as a cantilever under load Q, but the length L/2-x gradually decreases; E. sigma_y, τy are the young's modulus, yield strength, and shear strength, respectively, of the pin.

In fig. 17 (a), there is only one V cavity, which corresponds to cantilever Liang Gongshi (equation 1). But for the case of the coefficient k1=0, the details are similar as in fig. 17 (c), but L in (equation 1) is doubled because there is a pair of opposing V cavities. For both cases, the pin 1 is fixed to the pier by concrete casting. In contrast, when the curvature of the V-cavity is designed to be in asymptotic contact, as shown in fig. 17 (b), an analysis can be made by (equation 4); otherwise (equation 1) applies to the case in fig. 17 (b), but the coefficient k2=0. Optional components are bottom pad 5, top pad 7 and friction washer 6 in fig. 17, which provide weight transfer and lubrication functions. In accordance with the present technique, devices 17 (a) and 17 (c) are classified as "class I V-connection with back tension"; the pin with the hinge end in fig. 17 (b) is classified as "type II V connection with back tension".

Fig. 19 shows the V-cavity and anchor pin combination but with an additional V-guide tube (VGT) 9 or separate protective funnel 10 and protective tube 11, respectively, which protect the connected base body from damage caused by contact with the pin.

From fig. 18 (a, b), by quantitative calculation using equations (1-4), it can be found that a relatively large value of L, i.e., a large V cavity depth, is required to produce significant pull-up force and lateral resistance, as the angle β is typically small for deformed metal cantilevers. On the other hand, when the pulling mechanism is dominant, it will also introduce a significantly high shear force to the pin at the same time. To significantly improve performance without increasing the dimension L, another embodiment is introduced in fig. 20 (a), wherein a combination of a V-shaped protective sleeve 12 (hereinafter V-shaped protective sleeve) and a contact pad 14 is introduced in the design details, wherein the contact pad 14 may be the bottom pad 5 or the top pad 7 in fig. 17. The innovative feature of the V-shaped protective sleeve 12, having the function of the reinforcing pin, similar to that introduced by the shear reinforcement ring in fig. 13, is that it provides a quantified pull-up force with a given V-shaped slope according to the mechanism explained in fig. 18 (b). The connection with the V-shaped protective sleeve is classified as a "class III V-shaped connection with post-tension", for example as shown in fig. 20 (b).

Instead of the V-shaped protective sleeve 12, the embodiment shown in fig. 20 (c) is a design of the pin 13, the pin 13 having a locally enlarged diameter to obtain the specified angle β for the lifting mechanism in fig. 18 (b), while reinforcing the pin against shear forces. Furthermore, the embodiment of the end of the hinge pin 2 in fig. 17 (b) is also applicable to the pin 13 in fig. 20 (c), with friction washers 6 between the pairs of contact surfaces.

Obviously, when the pulling-up movement shown in fig. 18 occurs, an additional pulling force is created on the anchor pin 1, 2 or 13 in these figures. To reduce the magnitude of this additional tensile stress and accommodate large scale pulling-up motions, a buffer spring 18 is added in the detail view of fig. 20 (c), which belongs to the "class II V-connection with post-tension".

Fig. 21 (a) is a case where the V-shaped protection sleeve 12 is completely filled into the space of the V-shaped recess 3, wherein the basic embodiment is to use the protection sleeve as a shear key to strengthen the closed pin and to position the blocks to be connected. Such detail is more suitable for connecting a plurality of structural members vertically or horizontally. Fig. 21 (c) also illustrates an embodiment of forming post-tensioned structural reinforcement lines by connecting a plurality of double threaded pins 20 using connectors Vsocket 19. The coupler housing is secured with a polygonal head that fills in the 43V-shaped recesses with an additional cylindrical cavity in the bottom. In summary, fig. 21 (b, c) briefly illustrates an embodiment of a construction process for dry joining of a plurality of vertically aligned structural components, which means the following three enhanced structural functions: (i) Connecting a plurality of pins or rebars to form post-tensioned structural reinforcement lines; (ii) Reinforcing the structural reinforcement wire at the area around the contact surface pair by a V-shaped protective sleeve or coupler V-shaped protective sleeve; (iii) These blocks are positioned by a V-shaped sleeve or coupler V-shaped sleeve. The connection with connector V-boot shown in fig. 21 (a-c) is classified as a "class IV V-connection with back tension".

The use of pins to connect two structural members while limiting lateral relative movement between them is a common method of engineering and has been used for centuries; however, to the authors' knowledge, for all pin-like connectors applied to bridges and buildings so far, the two ends of the pin are respectively embedded in the connected structural parts, without approaching, except for the prior art figures 12-14 of the applicant of the present invention. However, in those disclosed prior art, the pin is not anchored for prestressing, nor is the pull-up mechanism of the present invention considered in the relevant design. Furthermore, the combination of the embodiment of the V-shaped protective sleeve in fig. 20 with the closing pin can also be regarded as a kind of pin for connection, but with the innovative feature of a locally enlarged diameter around the connection interface. This results in the embodiment of fig. 22 (a), "atypical pin" 48, characterized by a combined function comprising (i) a segment of length Lv2, lv3, lc0 and larger diameter than the other segments designed for shear strengthening and positioning; (ii) The cylinder segments of lengths Lc2 and Lc1 are designed to provide sufficient holding force by the body of the connection unit; (iii) Segments with lengths Lv1 and Lv4 and V-shape and reduced diameter are designed for guiding positioning; where (i) is an innovative feature beyond the traditional pins, the atypical pin 48 is hereinafter referred to as an "A1 pin". Atypical pin 49 is a degenerate case of an A1 type pin, where l_v1=l_v4=0, hereinafter simply referred to as "A2 type pin", whereas atypical pin 50 is another degenerate case of an A1 type pin, l_v2=l_v3=l_c0=0, hereinafter simply referred to as "A3 type pin".

When the atypical pin in fig. 22 (a) is designed as a central through-cylindrical hole through which the pin or tendon passes, this results in another embodiment of an innovative class of protective sleeves designed with additional shear bars around the interface between two connection units for post-tensioning while helping to locate the assembly, hereinafter referred to as "V-shear keys" or "V-shear keys". Fig. 22 (b) shows V-shaped shear keys, which respectively show V1 shear key of the protective sheath 51, V2 shear key of the protective sheath 52, and V3 shear key of the protective sheath 23. The V-shaped protective sleeve 12 previously described in fig. 20 can be regarded as a degenerate case of V1 shear key 51, where l_v2=l_v3=l_c0=l_c1=l_c2=0; degradation of the V1 protective sheath 53 in fig. 22 (c) is similar, but l_v1+.l_v4. Fig. 23 (c) shows how these V-shaped shear keys are additionally reinforced and post-tensioned on pins or tendons passing through the connection units around the contact interface between the units.

In the case of stacked and vertical post-tensioning of the blocks, as in fig. 21 (a-c), the weight of the blocks introduces additional friction on their contact surface pair, plus post-tensioning generated friction, which helps to resist any relative sliding and to facilitate the integrity of the connection structure. In contrast, for the back tension of a horizontally aligned structural block (e.g., a prefabricated segment bridge block in fig. 23), the weight of the structure is completely transferred into the shear force on the contact surface pairs. The V-shaped shear key and pin of fig. 22 is suitable for such applications. Figure 23 shows a segment bridge span back Zhang Shili where V-shaped shear keys 23 and V-shaped pilot pits 27 are used to mount the V-shaped shear keys.

Fig. 24 (a, b) shows the construction of a wet joint connecting two sets of i-beams 33 to the bends 28 at the top of the bridge pier 29, wherein tendon ducts 30 are prefabricated in each i-beam 33, and the post-tensioning operation includes two steps: (I) Tightening the anchor nuts 4 during or after the casting of the wet joint, depending on the location of the anchor location, which applies vertical compression to the joint; (ii) The tendons 35 are inserted through the guide tube 30, and the guide tube 30 connects the guide tube prefabricated in the wet joint and each i-beam 33, respectively. In fig. 24 (b), vertical post-tensioning is performed during the casting of the wet joint. The wet seam in fig. 24 includes two design details: (i) When seismic isolation is a major consideration, the cushion 32 and the cushioning material or bearing cushion 34 are disposed therein, while the V-shaped cavity 12 is not completely filled into the space enclosed by the V-shaped pit; thus, the pin can bend within the pit and may slide laterally relative to one another, which provides the effect of seismic isolation while triggering a heave mechanism to take advantage of the weight of the loaded superstructure to resist lateral sliding. The combination of pin, V-shaped dimple and V-shaped protective sleeve or V-shaped shear key can always be designed to be in a modifiable elastic state, according to equations (4-6), so that the structure has sufficient capacity to drive the connector back to its original state with engineering acceptable tolerances after the impact that caused the relative sliding passes. (ii) When structural integrity is a major consideration, the main beams are laid directly on top of the bent, as are the wet joints to be poured; cushion 32 and cushioning material or support cushion 34 are not required, but V-shaped cavities or V-shaped shear keys are installed on the connection to the pier to protect the pin.

Fig. 25 illustrates the construction process for the same application as fig. 24, but without dry joining by box 36 or block 37. In these dry connection blocks, pipes 44 for the vertical reinforcing pins 1 and pipes 45 for the horizontal tendons are prefabricated. The post-tensioning operation is performed by tightening the nut 4 on top of the dropped dry joint block (e.g. 36 or 37).

The dry connection in fig. 25 may require precise alignment of Ji Gongzi beams along the longitudinal position to ensure that the gap width between the connecting beams conforms to the size of the dry seam block and that the tolerances of the length and structure of the beams can be accommodated by deck seam expansion. For multi-span bridges, this can be tedious or even infeasible. This disadvantage can be resolved by using a combination of wet and dry seams, one after the other, as shown in fig. 26.

The construction of three-way cross-joints of a building structure using the innovative design details described previously and the procedures described in fig. 24-26 is shown in fig. 27

Verification and experimental verification of key embodiments

A series of experimental studies and numerical simulations have been performed to verify the concepts introduced by the authors in the art for post-tension free V-connectors, such as those in [1 ]. The results of these studies actually inspire the examples disclosed in the art.

Computational simulations were performed on a series of three-dimensional finite element models of bridge-to-bridge connection by pins embedded in regular pin connections or V-shaped pits, whether or not V-shaped sockets as described in fig. 20 were employed. The study compares the performance of three methods: (i) The connection is made in a cylindrical hole of the concrete matrix using a conventional pin; the corresponding three-dimensional finite element mesh is shown in fig. 28 (a); (ii) As shown in fig. 28 (e), the connection is made using straight pins within V-shaped pits, and fig. 28 (b) shows a corresponding three-dimensional finite element mesh; (iii) As shown in fig. 28 (f), the connection is made with a V-shaped protective sleeve in a V-shaped pit using straight pins, and two finite element meshes of different sizes are shown in fig. 28 (d), which meshes are used for design optimization. In both grids of fig. (c, d), the V-shaped protective sleeve is meshed as part of the pin; furthermore, the two ends of the pin engage as part of the upper and lower blocks, respectively, to avoid complex engagement of the anchors. These simplifications do not affect the mechanical properties of the connector.

The corresponding simulation includes two groups: a first group: the finite element model in fig. 28 (a, b, c), where the samples have the same vertical load, horizontal acceleration, coefficient of friction and materials of pins, pipes and concrete matrix; and having the same diameter for straight pins and straight portions of pins having different parameters; second group: the finite element model of the mesh in fig. 28 (d), where the pin and V-shaped protective sheath are larger in size than the other dimensions, under the same vertical load as the other dimensions, but with higher horizontal amplitude.

Fig. 29 shows a comparison of Von Mises stress calculation contours under the same loading conditions in fig. 28 (a) and 28 (b), where in theory Von Mises stress is the shear stress on an octahedron, equal to the maximum engineering shear stress multiplied by v 2. As described in the previous section, with respect to the conventional pin inserted into the cylindrical hole in fig. 28 (a), the calculation result of fig. 29 (a) shows that there is a significant high shear concentration in the local area around the contact interface between the upper and lower pier blocks, which in effect cuts off the pin quickly. In contrast, for the pin in the V-shaped cavity, the calculation in fig. 29 (b) shows that there is a high shear force where the pin begins to contact the merle pit in the region near the pit bottom. In the latter, the amplitude of the stress peaks is much lower than in fig. 29 (a). Fig. 30 is a series of snapshots of the calculated Von Mises stress contours under the increasing lateral load Q shown in fig. 18 in the case of fig. 28 (c), indicating that the lift mechanism becomes important when the lateral load Q is greater than Qf. These phenomena replicated by numerical calculation demonstrate the concept of the embodiment in fig. 18.

The experimental verification of the V-connector product series has been performed simultaneously in the university of berkeley in the united states PEER laboratory (pacific seismic engineering research center) and the national river-north-province water seismic research laboratory (HSER). These experimental studies were originally designed according to the embodiment of the V-connector with hinge pin of fig. 14, in which only one end of the pin is hinged as shown in fig. 17 (b), but the other end is free. However, through testing, a doming phenomenon has been observed, which validates the computer simulation in fig. 29, which in fact inspires the invention of the art. Fig. 31 is a photograph of test equipment set up in the pecker division PEER laboratory, california. FIG. 32 is a photograph of a China Hebei seismic isolation laboratory facility. FIG. 33 is a set of measured hysteresis curves for a V-connector sample according to the embodiment of FIG. 20 (c) that connects the upper bridge span and lower pier blocks, identical to the model of FIG. 28. In the figure, the horizontal axis is the lateral displacement and the vertical axis is the corresponding lateral resistance tested. In this figure, the lateral displacement is actually a relative sliding between the cross block and the pier block; the lateral resistance, indicated by the vertical coordinates, is the force generated by the installed V-connector against this relative sliding and the friction on the pair of contact surfaces between the two blocks. When the relative sliding exceeds 80 mm, a significant increase in resistance can be seen, which is about the radius of the opening of the V-shaped recess in the tested V-shaped connector sample. The resistance to abrupt rise at this distance means that the pins contact the edge of the roof pad, which supports the mechanism. This result verifies the critical embodiment of fig. 20 and verifies the feasibility of the V-connector in engineering applications.

Drawings

For a more complete understanding of the prior art, the present disclosure, and the advantages thereof, reference is now made to the following figures, in which:

FIG. 1 (a) illustrates how tensile stress in a bending beam is generated if there is no prestressing; in contrast, fig. 1 (b) shows a schematic diagram illustrating the post-tensioning of a beam with compressive prestressing, the corresponding compressive stress being exchanged with the tensile stress in (a) when the beam is under bending moment.

FIG. 2 highlights the engineering problem to be solved by the present invention, in which two common examples of crossover joints are given to highlight the complexity of stress distribution; for the conventional prestressing in fig. 1, it remains a challenge to ensure tensile and shear stresses in the concrete portion of such joints, two examples of which are: (a) A common joint between the pier top beam and the curved beam, and (b) a beam-to-column intersection joint for construction.

Fig. 3: (a) The prior art US389891, in which the pile is an assembly of a plurality of vertically arranged tubular drive housing parts, which are connected one to the other by means of penetrating prestressing tendons; (b) The critical embodiment of prior art US3703748 introduces details of the wedge-shaped anchors to both ends of the tendon.

Fig. 4: (a) The embodiment of prior art US1647925, which anchors the lower end of the tendon with a steel socket at the footing and secures the upper end of the tendon on top of the pile with a nut; (b) A recent patent application (CN 110685215A/CN 201910897918A) which is similar to the concepts in prior art US389891 and US1647925 but incorporates an additional steel sleeve to connect the rebars in adjacent pile segments directly above their contact surface pairs; (c) Another recent application (CN 109610304a/CN 201811608588.3) in which sockets 8 with constant cross-sectional geometry are present at the contact surface pairs.

Fig. 5 shows two couplers: (a) Means for connecting two tendon ends that are not aligned on one axis, US 6560939B2; (b) PCT/KR2006/004958, a threaded connector for two bars having a threat end along the same axis.

Fig. 6 is an embodiment of a bridge module of prior art US6742211 in which piles are made from vertically overlapping structural blocks on mating pairs of concave-convex downwardly contacting surfaces to increase lateral resistance to misalignment.

Fig. 7 shows a method of constructing a wet joint between two spans on a pier in prior art US3794433, which may be a revolutionary improvement in post-tensioning concrete bridge construction.

Fig. 8 is a cross joint of two rear Zhang Daoguan of US2950517 with saddle-shaped anchors for embedding a portion of a cross-laid rebar grid of a highway deck.

Fig. 9 is a prior art JP2011001717a (japanese patent) for treating the intersection joint of a concrete beam and a superimposed column, wherein an example is a side bolt steel set, ensuring that the column stands vertically and that the gap between the column bottom and the intersection joint of the beam is adjustable.

FIG. 10 is a detailed design of the Tennex department of transportation in the United states, wherein a general procedure is defined for casting a wet joint at the top of a column connecting two spans, either bridge piers or bends in the bridge piers, by which bolts are first cast into the column; then placing the ends of the two spans on the tops of the columns on two sides of the bolts; then casting the concrete mixture into the gap between the two span ends while tightening the bolts to apply pressure to a portion of the joint; wherein (a) and (b) are two standard designs, wherein the former provides an elastic pad below the seam and the asphalt fiberboard is used as a support pad. The network layout of the rebar within the wet seam is shown in (c). However, when the structure is subjected to a strong seismic impact, high shear stress concentrations may occur at the interface between the bridge pier and the wet joint, as shown in the left-hand graph of fig. 13.

Fig. 11 is a prior art JP200 8050820a (japanese patent) which describes the vertical connection of two structural blocks on a V-shaped sliding contact surface pair, and an anchor bolt fastened to the top. To accommodate horizontal sliding separation along the V-shaped surface, holes of larger diameter than the bolts are preformed in the upper block so that the bolts can move freely within the holes, which substantially negates the robustness of the connection provided by the top fastener.

Fig. 12 is an embodiment of the present inventors' prior art PCT/US2016/013741 that utilizes a combination of pins passing through V-shaped dimples to connect bridge piles to beams to increase the resistance to lateral shear, but does not require post tensioning means.

Fig. 13 is another embodiment of PCT/US2016/013741 which describes various designs of pin geometry featuring partial diameter enlargement or the use of additional shear strengthening rings to increase the ability to resist lateral shear forces.

FIG. 14 is another prior art PCT/US2018/013205 embodiment of the present inventors; unlike V-shaped dimples on both surfaces of two joined blocks, there is only one V-shaped dimple in the connector, but with either a fixed or hinge end pin.

Fig. 15 is an embodiment of a Friction Pendulum Bearing (FPB) of prior art US6021992, as well as a set of other FPB prior art. According to the pendulum principle shown on the right side of the figure, the device uses the lateral forces on the curved surface caused by the weight of the upper structure being carried to resist the horizontal inertia caused by the ground movement, but without the limitation of vertical separation between the connected structural components.

Fig. 16 is an embodiment of prior art PCT/US2012/0613127 (another invention of applicant) that uses the horizontal resultant force of the loaded superstructure weight on the V-shaped sliding surfaces to resist seismic induced lateral misalignment, while the horizontal sliding pins in (a) or the vertical stiffening pins (called fasteners) in (b) are, respectively, limiting the connected structural members from vertical separation.

Fig. 17 shows a key embodiment of the invention, characterized by the combination of a V-shaped cavity 3 and an anchoring pin 1 prefabricated in a lower block, wherein the benefits of the V-shaped cavity 3 include: (i) When the structure is subjected to extremely high external loads (such as strong earthquakes), providing a "buffer space" for the pin to bend, relative sliding is unavoidable, thereby avoiding the pin from being cut by the shear stress concentrations explained by the leftmost curve in fig. 13; (ii) The pulling-up motion of the connected superstructure blocks is introduced to take advantage of the horizontal resultant of the weight of the blocks introduced by the curvature of the pins to resist the seismic induced lateral motion, as will be further explained in fig. 18; (iii) providing room to strengthen the pin and expand the effect of the bump. The design details of the post-tensioned connection of the V-shaped cavity with the conventional anchor end in fig. 17 (a) and (c) are categorized as "type I V-shaped connection with post-tensioning force", and the pin with the hinge end in fig. 17 (b) is categorized as type II V-shaped connection with post-tensioning force.

Fig. 18 (a) is a graph of the profile of V-shaped cavity 3 in fig. 17 (b) or 17 (c), denoted Y (x); according to the curved configuration of half the length of pin 1 in fig. 17 (c) or the entire length of pin 2 in fig. 17 (b), designed under lateral force Q, if designed according to equations (1-6), progressive contact may be introduced between the pin and the pit surface, creating progressively increasing shear forces on the pin, as described in (b); (b) When the pin is bent, the transverse force Q is divided into sags according to angleResultant force directed at the contact surfaceAnd resultant force tangential thereto ∈ ->Which may be approximated by the derivative of the function determined by equations 1-4; the N reactant from the weight of the upper mass will be induced, helping to resist further lateral displacement; (c) The model of the asymptotic contact between the pin and the V cavity wall, from which the first ordinary differential equation 4 is derived, determines the curvature of the V-shaped pit.

Fig. 19 shows the protective concrete matrix with the addition of an additional V-guide tube (VGT) 9 or a separate protective funnel 10 and protective tube 11, respectively.

Fig. 20 (a) is an innovative detail view of a pair of parts of the V-shaped protective sleeve 12 and contact pad 14, with the optional angle β indicated by the pull-up effect in fig. 18 (b); this results in embodiments of "class II V-connection with post-tension" in (b) and (c), respectively; wherein (b) is a direct application of the pair of parts (a) of the connector of fig. 17 (a); in contrast, the embodiment of the hinge pin in fig. 17 (b) is applicable to (c), but the diameter of the pin is gradually increased, denoted 13. The V-shaped protective sleeve 12 also enhances the shear strength of the pin according to the mechanism described in (a); (c) The details in (a) include a spring 18, the spring 18 acting as a bumper to accommodate the lifting motion, thereby reducing tensile stress in the pin.

Fig. 21 (a) shows a detail of the V-shaped protective sleeve 12 fully filling the space of the V-shaped cavity 3, wherein the following embodiment is to use the protective sleeve to stiffen the pin while positioning the two blocks for connection. When multiple building blocks are connected for post-tensioning by this method, an embodiment employing a V-shaped boot as the connector for the pin by internal threads and nut heads is described in detail in (c), which is referred to as the connector V-boot, and is denoted as 19 in (b) and (c) of this figure; thus, the V-shaped cavity for coupler Vsocket also includes an additional cylindrical cavity at its bottom, indicated at 43 in this figure; and the pin has threaded ends in addition to one end anchored to the bottom; such pins are indicated as 20 in these figures. The V-connector with this detailed information is classified as "class IV V-connection with back tension".

Fig. 22 (a) atypical pin: a type A1 pin 48 in which segments of lengths Lv2, lv3, lc0 are designed for shear strengthening and positioning; cylinder segments of lengths Lc2 and Lc1 are designed for adequate retention; segments with lengths Lv1 and Lv4 and V-shaped reduced diameters are designed for guiding positioning. The A2 pin 49 is a degenerate case of the A1 pin, where l_v1=l_v4=0, and the A3 pin 50 is another degenerate case of the A1 pin, l_v2=l_v3=l_c0=0. (b) When the atypical pin of fig. 22 (a) is designed as a central through-cylindrical hole through which the pin or tendon passes, this results in another embodiment of an innovative class of protective sleeves designed with additional shear bars around the interface between two connection units for post-tensioning while helping to position for assembly, known as "V-shear keys", or abbreviated as "V-shear keys", an innovative class of protective sleeves designed with additional shear stiffeners around the interface between two connection units for post-tensioning while helping to position for assembly, parallel to the embodiment of (a); the V-shaped protective sleeve 12 previously described in fig. 20 can be regarded as a degenerate case of V1 shear key 51, where l_v2=l_v3=l_c0=l_c1=l_c2=0; similar to V1 protective sheath 53 in (c), wherein L_. Fig. 23 (c) shows how these V-shaped shear keys are additionally reinforced and post-tensioned on pins or tendons passing through the connection units around the contact interface between the units. It is demonstrated how these V-shaped shear keys are additionally reinforced and post-tensioned on pins or tendons passing through the connection units.

Fig. 23 is an example of a segment bridge post-tensioning in which the plurality of V-shaped shear keys 23 disclosed in fig. 22 are used in conjunction with V-shaped guide cavities 27 to mount the V-shaped shear keys.

Fig. 24 shows the construction of a wet joint for connecting two sets of I-beams 33 on the bent tops 28 of piers 29 and post-tensioned vertically by pins 1 and horizontal tendons 35 reinforced by V-shaped cavities 12 or V-shaped shear keys 23; wherein (a) describes the parts and components between castings in a wet joint; (b) presenting the wet joint after casting. Further, the vertical post-tensioning is performed by fastening the pin 1 with the anchor nut 4 in the middle of the wet joint. The combination of pin, V-cavity and V-sleeve or V-shear can always be designed to be modifiable elastic state according to equations (4-6), so that the structure has sufficient capacity to drive the connector back to the original state with engineering acceptable tolerances after the impact causing the relative sliding passes.

The construction process shown in fig. 25 is the same as that shown in fig. 24, but instead of wet seaming, a dry box 36 or a dry block 36 is used. Unlike the wet joint in fig. 24, the vertical post-prestressing is performed by fastening the pin 1 with the anchor nut 4 on the upper surface of the dry joint block.

Fig. 26: in order to install the gap between two connection beams when using the dry joint blocks or joint boxes and to ensure that the deck expansion joints can accommodate tolerances due to the manufacture and construction of the beams, the figure describes a construction process that applies a wet joint after one or both dry joints to accommodate deviations in the manufacture and construction of the multi-span bridge dry joints.

Fig. 27 shows the construction of a three-way cross joint of a building structure using the previously disclosed connection details and post-tensioning methods described in fig. 24-26.

FIG. 28 shows four exemplary three-dimensional finite element models of bridge spans connected to pier blocks by V-connectors; numerical simulations were performed with these models to verify concepts based on embodiments disclosed in the art; wherein (a) is a conventional pin connection; (b) Fig. 17 (e) and 20 (f) are models of V-type connectors according to embodiment (e). In models (c) and (d), the V-shaped protective sleeve is modeled as part of the pin; while the anchors in the model (b, c, d) are modeled as physical connections to the block.

FIG. 29 is a comparison of the calculation results between case (a) and case (b) in FIG. 28; wherein a high shear stress concentration occurs at the interface between the two blocks in (a), i.e. a conventional pinning; in contrast, the highest shear stresses of moderate magnitude occur around the area where the pin contacts the V-shaped cavity.

Fig. 30 shows a series of snapshots of case (c) of fig. 28, wherein the pull-up phenomenon is shown in (d) when the lateral force Q reaches a certain level.

FIG. 31 is a test facility of the PEER laboratory of the university of California Bokrill division civil engineering system; the facility was designed to test the performance of the V-connector in a physical model, as shown in fig. 28.

FIG. 32 is a test facility of the Hebei province of China, hemiq water f seismic research laboratory (HSER) for testing V-connectors.

FIG. 33 is a set of measured hysteresis curves for the V-shaped connector according to the embodiment of FIG. 20 (c) wherein the horizontal coordinate represents lateral displacement and the vertical coordinate represents lateral resistance; when the lateral displacement exceeds 80 mm, the resistance increases significantly, which is about the radius of the V-shaped cavity opening in the test specimen, which means that the pull-up creates resistance.

Claims

1. A device for connecting components of a structural system, wherein the structural system refers to a large civil engineering building structure such as a bridge or a house; here, the components refer to beams, columns, foundations, etc. constituting units of the structure; the device here comprises a connection of at least two parts, the surfaces of which at the connection are called end faces, which are not in complete contact, all of these non-contacting end faces constituting a boundary of a space, which boundary may comprise one or more planes to ensure the space is closed; all the components to which the end faces belong form a connection group, the connection device further comprising:

a) Concrete blocks placed in said space, noted as a "filling member" belonging to said connection group;

b) At least one pin made of a single or different material including, but not limited to, rods, bars, and steel strands made according to prestressed concrete industry specifications;

c) At least one set of anchor assemblies, wherein the at least one set of anchor assemblies may be used to apply a pre-stress;

d) At least one of the parts comprises at least one V-shaped cavity, hereinafter referred to simply as "V-cavity", preformed and open at its surface, through which the pin passes and is inserted at its bottom into the base of this part;

the set of connecting members comprises at least one member below the infill member, this member being hereinafter referred to as "base member", wherein "below" refers to the direction in which gravity is directed; the base part and the parts below the base part constitute a "lower column part set", which may comprise only the base part;

the infill members and the members contacting thereabove constitute an "upper member group", wherein "above" refers to a direction opposite to gravity, the upper member group may include only the infill members;

a first end of the pin is anchored to one part of the lower set of column parts, hereinafter referred to as the "lower anchor part", the pin extends through all parts of the lower set of column parts above the lower anchor part at the end face of the base part, and a second end of the pin penetrates the infill part and is anchored to one part of the upper set of parts, hereinafter referred to as the "upper anchor part";

The lower anchor member, the upper anchor member, and all other members through which the pin passes between the two members constitute an "anchor member set"; the pin binds all the components of the anchoring component group together while the prestressing operation can be accomplished by applying a tensile force to one end thereof;

a pair of contact surfaces of two adjacent parts in the anchor part group is simply referred to as "contact surface pairs", the two adjacent parts are simply referred to as "part pairs", and the contact surface pairs between the infill part and the base part are simply referred to as "main contact surface pairs".

2. The structural connection device of claim 1, wherein at least one of the pins comprises a portion of progressively increasing diameter passing through at least one of the V-shaped cavities.

3. The structural connection of claim 1, wherein said V-cavity comprising at least one preformed and open surface and comprising specific design details to enhance the bearing capacity of said pin in a direction non-parallel to the post-pre-stressing direction, avoiding shear failure by transverse forces perpendicular to the pre-stressing direction when a contact surface through which said pin passes is slipped, said specific design details comprising three design parameters of V-cavity depth, opening diameter, and V-cavity curvature determined according to formulas 1-6 and analysis of the specification, to achieve at least one of the following functions:

a) Reducing stress concentrations created by lateral forces on the pin;

b) Providing a buffer space to allow the pin to bend when one of the contact faces slides relatively to avoid shearing;

c) Gradually contacting the V-chamber wall as the pin flexes, progressively increasing resistance to the relative sliding;

d) The designed lifting separation is caused, so that the gravity and the prestress of the component are utilized to resist the further relative sliding caused by the transverse force;

e) Enhancing the shear capacity of the pin;

f) Ensuring that the pin is in a self-restorable state,

the self-restorable state means that the pin has a function of driving the connected component to automatically restore to the original state after the lateral force is removed, and the deviation is within an error range allowed by engineering design specifications.

4. The structural attachment device of claim 1, wherein the base member further comprises a lower top plate that is preformed or mounted on a surface of the base member that contacts the filler member, such that a surface of the lower top plate that does not contact the base member replaces a surface of the base member that is centered on the primary contact surface.

5. The structural connection device of claim 1, wherein the infill member further comprises an upper top plate that is preformed or mounted on a surface of the infill member that is in contact with the base member, such that a surface of the upper top plate that is not in contact with the infill member replaces a surface of the infill member in the main contact surface pair.

6. The structural connection device of claim 1, further comprising a friction washer interposed between the surfaces of the primary contact surface pairs.

7. The structural attachment device of claim 1, wherein at least one V-shaped cavity comprises at least one V-shaped protective sleeve geometrically conforming to an inner wall thereof, said pin passing through said V-shaped protective sleeve.

8. The structural connection device of claim 1, wherein at least one of the pin penetrating or passing members comprises at least one protective sleeve through which the pin passes.

9. The structural connection device of claim 1, wherein at least one component comprises at least one V-shaped set of protective sleeves, the set of protective sleeves being preformed or embedded in the component, the pin passing through the set of protective sleeves; the V-shaped protective sleeve group comprises a cylindrical part and a bell mouth part.

10. The structural attachment of claim 1, wherein the first end of the pin is welded with an anchor end non-parallel to the pin, the anchor end being pre-anchored in the lower anchor member, the anchor end having a length at least twice the diameter of the first end of the pin.

11. The structural connection device of claim 10, wherein the pin first end is anchored to the lower anchor member by an anchor device.

12. The structural interface of claim 1, wherein the lower column member set comprises only a base member, and wherein the first end of the pin is hinged by a hinge sleeve set comprising a hinge cover and a hinge mount preformed in or bolted to the base member main contact surface.

13. A structural connection device according to claim 3, comprising

At least one pair of said V-cavities, abbreviated as "V-cavity pair", wherein each V-cavity is respectively preformed in adjacent contact surfaces of the pair of contact surfaces comprised by said pair of parts, two V-cavity openings being opposite to each other;

a V-shaped reinforcing sleeve abbreviated as a V1 sleeve is arranged in the cavity contained in the V cavity pair; the geometry of the V1 sleeve is composed of two cones which are connected with opposite inverted bottom surfaces, the bottom surfaces of the two cones are identical, but the heights and the conicity of the two cones may not be completely consistent, the V1 sleeve is provided with a cylindrical hole positioned at the geometric center of the two cones, and the pin penetrates through the cylindrical hole;

the curvature of the inner wall of the first V cavity of the V cavity pair is according to the special design, and the first cone of the V1 sleeve is contained in the first V cavity and the taper angle beta matched with the curvature of the inner wall of the V cavity so as to obtain the lifting mechanism and force as shown in figure 20;

The curvature of the inner wall of the second V cavity of the V cavity pair is designed according to the special design to obtain the self-recovery function, and the curvature of the inner wall of the second V cavity of the V cavity pair is matched with the shape of the second cone of the V1 sleeve in a gapless manner.

14. A structural connection device according to claim 3, comprising

at least one V-shaped reinforcing sleeve called V1 sleeve for short is arranged in a cavity contained in the V cavity pair; the geometry of the V1 sleeve is composed of two cones which are connected with opposite inverted bottom surfaces, the bottom surfaces of the two cones are identical, but the heights and the conicity of the two cones may not be completely consistent, the V1 sleeve is provided with a cylindrical hole penetrating through the geometric center of the two cones, and the pin penetrates through the cylindrical hole;

the tapered opening geometry of the first V-chamber of the V-chamber pair is designed according to the specific design to achieve the self-restoring function and to strengthen the pin strength, which is in gapless fit with the V1 sleeve first cone profile.

The tapered opening geometry of the second V-chamber of the V-chamber pair is designed according to the specific design to achieve the self-restoring function and to strengthen the pin strength, which is in gapless fit with the V1 sleeve second cone profile.

15. A structural connection device according to claim 3, comprising

-at least one V-shaped connecting sleeve, abbreviated as "V-sleeve", the geometry of said V-sleeve being composed of two cones joined at opposite inverted bases and a nut-like extension at the top end of the first cone, the two cones having the same base but possibly not identical heights and conicities, said V-sleeve having a cylindrical screw hole extending through the geometrical centre of said two cones, said cylindrical screw hole containing a preformed internal thread, the threaded ends of said rods being screwed into this cylindrical screw hole and being connected to each other;

-at least one of said pins is formed by connecting at least two segments of bars, each of which is provided with a pre-threaded at least at one end and can be bolted to the other bar by means of said V-connection sleeve;

-at least one pair of said V-cavities, abbreviated as "V-cavity pair", wherein each V-cavity is prefabricated in a respective adjacent contact surface of the pair of contact surfaces comprised by said pair of parts, two V-cavity openings being opposite to each other; the bottom of the first V-shaped buffer cavity of the V-shaped cavity pair further comprises an extended cylindrical cavity, and the cylindrical cavity of the first V-shaped buffer cavity can accommodate a nut-shaped extension body at the top end of the first cone of the V-shaped connecting sleeve;

-the cone opening geometry of the second V-chamber of said V-chamber pair comprises the second cone of said V-nipple without clearance;

-the two V-cavity cone opening geometry of the V-cavity pair is according to the special design to achieve the self-restoring function and to strengthen the pin strength;

the lowermost one of the bars constituting the pin is anchored at a first end to the lower anchor,

the part adjacent to the lower anchoring piece is named as a 2 nd part, and a first V connecting sleeve is embedded in the V cavity pair of the contact surfaces of the two parts to bolt the second end of the lowest rod piece and the lower end of the upper rod piece, and the upper rod piece is named as a 2 nd rod piece;

the part adjacent to the part 2 is designated as part 3, and the V-cavity pair of the contact surfaces of the two parts is internally embedded with a second V-connection sleeve to bolt the upper end of the rod 2 and the lower end of the rod above. This is repeated until the upper end of the uppermost rod is anchored with the upper anchor.

16. The structural connection device of claim 1, wherein at least one set of said anchor assemblies includes an anchor load pad and at least one anchor nut, wherein at least one end of said pin includes threads, and wherein said end is secured by said anchor nut through said anchor load pad.

17. The structural connection device of claim 16, wherein at least one set of the anchor assemblies includes at least one anchor spring between the anchor load pad and the anchor nut.

18. The structural attachment device of claim 16, wherein at least one set of said anchor assemblies further comprises an anchor wedge having a central through bore, said anchor wedge being a trapezoidal cylinder of linearly varying diameter; at least one component of the structural attachment system is anchored by the anchor assembly to the end of the pin, whereby the component contains a preformed V-shaped open cavity open at its surface, the anchor wedge can be wedged into the V-shaped open cavity, and the pin shaft extends from the bottom of the V-shaped open cavity, through a central through hole of the anchor wedge and is anchored by the anchor assembly.

19. The structure connection device of claim 1, wherein the infill part is formed by casting the space with concrete at the site where the structure system is constructed, hereinafter referred to as "wet joint"; a prefabricated reinforcing steel bar network is arranged in the space before the wet joint is molded, prefabricated extension reinforcing steel bars are arranged on the end face of at least one part of the connecting part group except the base part and the wet joint, and the heads of the extension reinforcing steel bars are in binding connection with the prefabricated reinforcing steel bar network; there are one or more prefabricated V-cavities for the reinforcement network, at least one of said pins passing through the V-cavities being prearranged in said space for pouring concrete and then anchored with said wet joint.

20. The structural connection of claim 19, further comprising a steel strand and a plurality of sets of pre-stressing anchors defining the lower and upper sets of anchor members as a "2 nd pre-stressing combination" with at least one of the members having a pre-formed through-hole therein, said through-hole forming a through-passage with the pre-formed through-hole of the other member in said wet joint and in said combination, said steel strand being capable of passing through said passage and being capable of anchoring and pre-stressing at both ends.

21. The structural connection of claim 1, further comprising a steel strand and a plurality of sets of pre-stressed anchors, said infill being formed from concrete in a form that is compatible with said space geometry and may not be in the field, hereinafter referred to as a "dry joint"; the dry joint comprises an internal cavity and at least one preformed through-hole, one opening of the at least one through-hole being directed towards the base part; the components of the anchoring component group excluding the lower column component group and the upper component group are defined as a "2 nd pre-stressing combination" in which at least one through-hole is preformed in at least one component, said through-hole forming a through-going passage with the preformed through-hole of the other component in said dry joint and in said combination, through which passage said steel strand can pass and can be anchored and pre-stressed at both ends.

22. An apparatus for reinforcing a connection in a structural system, wherein the structural system is a civil engineering structure, such as a bridge or a building, wherein the units refer to components consisting of beams, columns, footings and segments of these elements in the structural system, wherein the apparatus comprises:

at least one of the shaped pins is provided with a pin,

a pair of units;

wherein the pair of units (hereinafter simply referred to as "unit pairs") are connected by at least one external force that is not parallel to at least one pair of contact surfaces of the unit pairs, wherein the pair of contact surfaces (hereinafter simply referred to as "surface pairs");

wherein the atypical pin is used to limit relative sliding within the surface pairs; wherein the atypical pin is composed of the following three parts in the length direction:

two ends, each having a constant cross-sectional geometry and size, respectively;

a middle portion having a constant cross-sectional geometry and size, wherein the cross-sectional area of the middle portion is greater than the cross-sectional area of either end portion;

two transition portions starting from both ends of the intermediate portion, the dimensions of which decrease from the dimensions of the intermediate portion cross-section to the dimensions of the two corresponding end portion cross-sections, respectively, at a constant rate;

Wherein the cell pair comprises at least one pair of cavities, referred to as a "cavity pair", wherein in the cavity pair each cavity is preformed into each surface of the surface pair and the openings of the two cavities are opposite to each other; wherein each cavity is adapted to the geometry and size, respectively, of a portion of an atypical pin consisting of one end portion, a transition portion adjacent to said end portion, and half of an intermediate portion adjacent to said transition portion, without being in proximity;

wherein the atypical pin is hereinafter referred to as "A2 profile pin".

23. The apparatus of claim 22, wherein the atypical pin further comprises two extension portions protruding from both ends, respectively, wherein a geometry and a size of a cross section of each extension portion is identical to a geometry and a size of a cross section of each adjacent end portion at each end portion of the A2 pin, but the size is further reduced at a constant rate when a distance between the outer portion and the end portion of the adjacent A2 pin increases, wherein the atypical pin is hereinafter referred to as an "A1 profiled pin".

24. The device of claim 22, further comprising a rod or tendon, a plurality of post-tensioning anchors, and a plurality of units; wherein each unit has at least one prefabricated or pre-machined tube, wherein the A2 pin is further manufactured with a centered through-cylindrical hole, hereinafter referred to as a "V2 shear key", wherein the centered through-cylindrical hole connects one tube in each unit to form a tube, wherein a rod or tendon is anchored through the tubes at both ends for further post-tensioning.

25. The apparatus of claim 22, further comprising at least two rods, a plurality of rear Zhang Maogu for the rods, and a plurality of units; wherein each unit has at least one prefabricated or pre-machined pipe, wherein the A2 profiled pin is further manufactured with a centered through-threaded hole, and is hereinafter referred to as "double V-nipple 2", wherein the centered through-hole connects one pipe in each unit to form a pipe, wherein the pipe is divided into two sub-pipes: the first sub-pipe starts from the middle of the double V-connection sleeve 2 protective sleeve and passes through all units on one side of the double V-connection sleeve 2, wherein the first end of the first rod passes through the first sub-pipe and is screwed halfway into the double V-connection sleeve 2, wherein the second end of the second rod passes through the second sub-pipe and is screwed halfway into the double V-connection sleeve 2 socket.

26. The device of claim 23, further comprising a rod or tendon, a plurality of post-tensioning anchors, and a plurality of units; wherein each unit has at least one prefabricated or pre-machined tube, wherein the A1 profiled pin is further caused to have a central through cylindrical bore, hereinafter referred to as a "V1 shear key", wherein the central through cylindrical bore connects one tube in each unit to form a tube, wherein a rod or tendon is passed through the tube and anchored at both ends for further post-tensioning.

27. The apparatus of claim 23, further comprising at least two rods, a plurality of rear Zhang Maogu for the rods, and a plurality of units; wherein each unit has at least one prefabricated or prefabricated pipe, wherein the A1 profiled pin is further manufactured with a centered through-threaded hole, and is hereafter referred to as "V1 nipple", wherein the centered through-threaded hole connects one pipe in each unit to form a channel, wherein the pipe is divided into two sub-pipes: a first sub-pipe starts from the middle of the V1 connection sleeve and passes through all units on one side of the V1 connection sleeve, wherein a first end of a steel strand passes through the first sub-pipe and is screwed into the V1 connection sleeve halfway, wherein a second end of the steel strand passes through a second sub-pipe and is screwed into the V1 connection sleeve halfway.

28. An apparatus for reinforcing the connection of units in a structural system, wherein the structural system is a civil engineering structure, such as a bridge or a building, wherein a unit refers to one member of the group consisting of beams, columns, footings and segments of these members in the structural system, wherein the apparatus comprises:

at least one special-shaped connecting sleeve is arranged on the connecting sleeve,

at least one of the steel bars or steel strands,

At least one of the pre-stressed anchor ends,

a plurality of units;

wherein each unit comprises at least one prefabricated or prefabricated pipe and the pipes are formed by connecting one pipe of each unit; wherein tendons pass through the conduit and are anchored at both ends by at least one post-tensioned anchor; wherein a prestressing force is performed which connects all the units together;

wherein a pair of cells (hereinafter simply referred to as a "cell pair") are connected by post-prestressing exerting a force non-parallel to a pair of contact surfaces of the cell pair, which pair of contact surfaces are hereinafter simply referred to as a "surface pair";

wherein the special-shaped connecting sleeve is used for limiting the relative sliding in the surface pairs

A middle portion having a constant cross-sectional geometry and size;

the two transition portions start from both ends of the intermediate portion respectively, gradually decreasing in size at a constant ratio;

wherein the cell pair comprises at least one pair of cavities, called a "cavity pair", wherein in the cavity pair each cavity is prefabricated in one surface of the surface pair and the openings of the two cavities coincide with each other; wherein each cavity is adapted to a shaped geometry and size consisting of one transition portion and half of the intermediate portion, respectively, without being in close proximity;

Wherein the rod or tendon passes through a shaped connection sleeve within the conduit, wherein the shaped connection sleeve is hereinafter referred to as a "V3 shear key".

The apparatus of claim 28, further comprising at least two rebars, a plurality of prestressing anchors connecting the rebars, wherein the V3 shear key is further manufactured with a centered through-hole bore and is hereinafter referred to as a "V3 nipple", wherein the centered through-hole bore connects one through-hole in each cell to form a passageway, wherein the through-hole is divided into two sub-passageways: a first sub-passage starting from the middle of the V3 connection sleeve and passing through all units on one side of the V3 connection sleeve, wherein a first end of a first reinforcing bar passes through the first sub-passage and is screwed into the V3 connection sleeve midway through the passage, and the other end of the first reinforcing bar is anchored by a prestressed anchor; wherein a second end of the second rebar passes through the second sub-passageway and is threaded into the V3 connection sleeve midway through the passageway and the other end of the second rebar is anchored with a pre-stressed anchor.