WO2019139580A1

WO2019139580A1 - A class of connectors to fast assembling of parts into a structure with robust connection and vibration mitigation

Info

Publication number: WO2019139580A1
Application number: PCT/US2018/013205
Authority: WO
Inventors: Su Hao; Alexander J HAO
Original assignee: Su Hao
Priority date: 2015-01-24
Filing date: 2018-01-10
Publication date: 2019-07-18
Also published as: CN110637125B; CN110637125A; WO2016118430A1

Abstract

A class of connecting-apparatuses that can be used as a connecter to connect two units in a structural system, such as a bridge or a building, and as a supporter to carry the loads transferred from one unit to another, for examples, gravity load. Said apparatus, termed as V-connector, is originated from the V-concept in [1], which provides robust connection as cast-in-place concrete structure under regular service condition while works as isolation device when the structural system is struck by strong earthquakes. Said apparatus is an assembly that comprises a designed stabilization-pin and a pad that is mounted onto one surface of the first unit, whereas a designed V-shaped cavity is pre-cut or precast on one surface of the second unit that, optionally, is with a builtin V-shaped guiding tubes, another pad on its surface, and a washer between the two pads.

Description

A Class of Connectors to Fast Assembling of Parts into a Structure with Robust

Connection and Vibration Mitigation

Citation: Previous invention patents that have similar functions as the disclosed embodiments but do not cover the unique technique of the claimed inventions in this application:

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PCT WO 2005/031088 A2 Apr. 7, 2005

Other References

[1] Federal Emergency Management Agency (FEMA), Reports 350-353, 2000

[2] USGS Records:

[3] California Department of Transportation (Caltrans), "The Continuing Challenge: The Northridge Earthquake of January 17, 1994".

[4] ASCE/SEI, "Minimum Design Loads for Buildings and Other Structures", 1995-2015 versions.

[5] "LRFD Bridge Design Specifications", AASFITO, the 1^st (1994) to the 7^th Editions (2015)

[6] AASFITO "Guide Specifications for Seismic Bridges' Design", 2^nd Ed., Second Edition, 2014

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

[8] TRB NCFIRP 12-68, Final Report: Rotational Limits for Elastomeric Bearings, 2004.

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

[10] Texas Transportation Institute 2012 URBAN MOBILITY REPORT, December, 2012.

[11] FHWA, Urban Congestion Trends (annually)

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

[13] Kelly, J. M., 1997, "Earthquake-resistant design with rubber", 2nd Ed., Springer, London. [14] "Rotation Limits for Elastomeric Bearings", Report 12-68, University of Washington, 2006 (published as report NCHRP 596, 2008). Civil, Structural & Environmental Eng. , University at Buffalo

[15] Buckle, I., Nagarajaiah, S., and Ferrell, K. 2002. "Stability of elastomericisolation bearings: Experimental study." J. Struct. Eng., 128(1), pp3-ll.

[16] Hao, S., PCT/US2012/061327

[17] Hao, S., Presentation at the Research Institute of Highway (RIOH), Beijing, China, "Exploration,

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[18] Hao, S., Presentation at the AFF50 Committee Meeting, 2015 TRB Annual Conference, Jan. 11^th,

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16 figures, 23 claims Reference to Related Applications

This application is a continuation-in-part of PCT application No. PCT/US2016/013741, filed on January 16, 2016 and entitled“A Class of Seismic-Isolation Connectors Providing Robust Connection Close to Cast-in-Place While Enabling On-Site Assembling and Fast Construction for Bridges and Buildings”, the entire contents of which are incorporated by reference herein, which claims the benefit of the following applications, the entire contents of each of which are incorporated by reference herein:

U.S. Provisional Patent Application No. 62/163,258, filed January 24, 2015 and entitled“A Class of Seismic-Proof Connectors to Protect Buildings and Bridges from Earthquake Hazards and Enable Fast Construction” ;

ET.S. Provisional Patent Application No. 62/356,043, filed June 19, 2011 and entitled“3V- Bearings for Bridges and Buildings Seismic Isolation, with and without Sliding Pin(s)” ;

ET.S. Provisional Patent Application No. 61/163,258, filed June 16, 2011 and entitled“Designs of V-Shaped Elastomeric Bearings (VEB) for Seismic Isolation” ;

U.S. Non-Provisional Patent Application No. 14/986,725, filed January 4, 2016 and entitled “Class of Seismic-Isolation Connectors Providing Robust Connection Close to Cast-in-Place While Enabling On-Site Assembling and Fast Construction for Bridges and Buildings” ;

U.S. Non-Provisional Patent Application No. 14/672, 172, filed May 28, 2015 and entitled“A Class of Seismic-Proof Connectors and Methods to Protect Buildings and Bridges from Earthquake Hazards and Enable Fast Construction” ;

U.S. Non-Provisional Patent Application No. 13/163,724, filed June 11, 2011 and entitled“One- Way and Two-Way(360 degrees) V-Shaped Elastomeric Bearings for Seismic Isolation, with and without Sliding Pin(s)”; PCT/US2012/063127, filed on November 2, 2012 and entitled“A Class of Bearings to Protect Structures from Earthquake and Other Similar Hazards”.

The innovative embodiments were disclosed to public through the first inventor’s presentations at the 2015 to 2018 Annual Conferences of TRB (Transportation Research Board) at Washington DC[ 18-20] as well as through the inventor’s materials sent to research partners and government officers with legal records.

Field of Invention

This application relates to the inventions for a class of apparatuses applied for engineering structures such as bridges and buildings, wherein a structure comprises multiple major structural parts, wherein each part has its own functions to said structure’s integrity; for example, a bridge has a superstructure that includes the beams that span over piers, and a substructure that contains piers and footing or other kinds of foundations. Similarly, a building’s superstructure can be an assembly of several stories. Wherein said apparatuses, termed“V- Connector”, connecting adjacent two said parts within a said structure. Wherein said V- Connector has the following functions: (i) provide a robust tie between the connected two said parts in a said structure; (ii) reduce vibrations and associated transient force flows, for example, inertia, from one part to another when the structure is struck by dynamic loads, for example, that caused by an earthquake; (iii) be able to shift said structure’s natural frequency when struck by said dynamic loads, so as to avoid resonated vibration that may destroy said structure; (iv) enable to prefabricate said parts in remote factory and assemble them into a said structure on designated construction site while assure required integrity and robustness; (v) assembled said part can be easily replaced or retrofitted when it is necessary. Therefore, said V-Connector can be used as seismic isolation bearing or connector in bridges and buildings for seismic-protection, or as connectors for fast construction of such a structure, or for the both. Method for fast construction is often termed“accelerated construction and replacement” by civil engineers; for example, “accelerated bridge construction (ABC)” is a direction currently promoted by FHWA(Federal Highway Administration) for US bridges’ construction community. The invention disclosed by this application is an innovative method for ABC: assembling a bridge on site as a module structure while preserving the same integrity and robustness as those bridges constructed by conventional method.

Background of the invention

The devastations earthquakes, such as Sendai of Japan in 2011 and Haiti of 2009, remind us of the continuing threat from nature to human-being’s life, particularly, for the regions with high seismic risk in United States and those in the world. A mission to engineering community forever is to build our habitations and facilities that will sustain these kinds of disasters.

An earthquake is a sudden tectonic-plate’s movement that radiates stress waves, by which the lethality to a structure comes from the inertia force due to wave-induced ground accelerations. The amplitude of such an acceleration and resulted inertia force in a structure can be elevated significantly when the structure’s self-vibration is resonated by an earthquake.

In the perspective of seismic protection, a primary requirement for a civil engineering structure, such as a building or a bridge, is integrity, which means that major structural parts of a construction system are supposed to be integrated as a solid frame that can be survive during future earthquakes. The design philosophy from this perspective can be termed“robust design”. Nevertheless, from the viewpoints of economy and construction capability, it is not always feasible to build a building or a bridge as strong as a banker.

Hence, another philosophy in modern engineering community, termed“isolation design”, emerges. It’s concept is to allow a structure temporally losing its integrity when struck by an earthquake through intentionally designed mechanism, for example, temporally weakening some structural parts or the connections in-between, so as to reduce or isolate inertia forces within the part directly exposure to earthquake and to minimize the damage to entire structure. This is because such temporally wakening is able to shift a structure’s natural frequency, which may avoid the resonant vibrations associated with the frequencies window caused by an earthquake. For example,“strong column and weak beam” is such a principle for seismic-resistant design for buildings [1]; it requires to design a building’s components, such as beams, with relatively-high flexibility so that these components will deflect first during an earthquake, in exchange of the stability of vertical load-carrying parts such as columns. Another method by this philosophy is to utilize seismic isolation bearings to provide the flexibility that a weak beam does; such a bearing allows temporally relative movement between connected parts, such as sub and superstructure of a building or a bridge, which confines the related impacts within the substructure exposure to earthquake-induced ground acceleration while shift the structure’s natural frequency to avoid resonance.

For civil engineering structures, bearing is a component between vertically-overlaid structure’s parts, for which a general function is to transfer the gravity of the part above to the part beneath. Earthquake loads, As compared with gravity, introduce horizontal and vertical accelerated motions and associated inertia forces. The bearing-products currently available in market are designed with the capacity to protect the impact of earthquakes within a given level of lateral accelerated wave motions according to the majority of historic recorded damages caused by past earthquakes, whereby the remaining challenges are: (i) for higher capacity to protect a structure against stronger earthquake, it will request not only bigger bearing’s dimension but also larger seat for the structural part that carries the bearing, which often introduces significantly high additional cost; (ii) in those areas that are close to earthquake’s epicenters, vertical acceleration is generally with the same amplitudes as that of horizontal or higher. Particularly, recent earthquakes, for examples, that in Big Island at 2005, Chili at 2009, and Sendai of Japan at 2011, remarkably-high vertical ground accelerations were presented in the area far away from epicenter. A striking fact revealed by the Sendai’s earthquake is that, for many bridges survived from the first waves of ground motions, their superstructures were washed away by the following tsunami because the seismic-isolation bearings in those bridges only have the capacity to protect horizontal vibrations. Obviously, for structural designs in the region with high seismic risks, it is crucial to find the balance between structural robustness desired in general and temporal flexibility required when an earthquake occurs. When seismic isolation bearing applies, an existing challenge is how to implement vertical reinforcement.

A structure by“robust design” has solid connection between connected parts along all directions. For regular concrete structures, by this design philosophy the common construction procedure is termed“cast-in-place” (CIP), i.e. to build extra formwork to cast a structure as a piece of concrete configuration. In western coast of US, the majority of concrete bridges were built by CIP. As compared with other construction methods, for example, prefabricate concrete beams in factories or other convenient places and then assemble the parts on site by seismic bearings, CIP is generally time-consuming and less cost-effective. The formwork for on-site casting generally takes about 20-70% share of total construction cost. On the other hand, resonated vibrations are easily triggered for CIP-constructed tall buildings or bridges with high piers.

Beside integrated design and isolation bearing, another methodology is termed“vibration mitigation” that has been applied in some buildings and bridges. Its concept is to add additional mass to a structural system through elastic connection, which shifts the original system’s natural frequency into a spectrum of frequencies for the new system depending upon the relative motion between the original and added mass when excited by external vibration; this keeps the new system off resonance. However, though resonant vibration is mitigated, the external excitation’s acceleration transferred to the system remains. Therefore, this method is more successful for the cases with long duration but weak external vibration resource, for example, wind-induced vertices.

While engineers are exploring better design philosophies and methods of seismic- resistant design in the regions with high seismic risks in US, accelerated construct and rapid retrofit are the general needs of bridge engineering for the country. It has been reported [10, 11] that, 2012 in United States, the average congestion time per day is 4.14 hours; the resulted economic loss is about $l2l-billion at the year, as compared with $24-billion at 1982. Historical experiences also tell that after each major earthquake in past, timing for fast retrofit and replacement of damaged buildings and life-line bridges means saving lives, for which economic consideration becomes the secondary. For all of these an outstanding challenge is: how to design a bridge or a building that is sufficiently strong and that can be built economically within minimized construction-duration, with the least efforts for maintenance, and easily to be retrofitted or replaced timely. To this end, innovative apparatuses for large-scaled civil engineering constructions, which has the capability to protect a structure from strong earthquakes and tsunamis while be able to provide both the solidness required under regular service condition and the convenience for fast construction and retrofit, will bring broad impact to construction industries and for public safety. Based on the requirements in the design specifications [4-7], the experiences of the catastrophic earthquakes [2], as well as the research reported in past, for examples, these listed in [1,3,7-9,12-18], the inventor of this application suggests the following basic criteria for a seismic-proof connector that be able to protect a bridge or a building from earthquakes or other kinds of dynamic impacts along all directions:

(A) Robustness: a stable connection under regular operating condition.

(B) Fuser: capable to accommodate a temporal separation between connected structural parts when one of them is dragged by a sudden accelerated motion that may be caused by earthquake, barge or vessel’s collision, or explosion; such a separation is able to reduce inertia-induced forces in both parts substantially.

(C) Self-healing: capable to self-restore the structure back to original state after an accelerated motion or back to a state that is with engineering acceptable deviation from original state.

(D) Integrity: during a temporal separation the connector should always keep the connected parts as an integrated system, in other word, the separation (B) should not result in permanent detachment, which is particularly important for the case when a superstructure of a bridge or a building is struck by impacts, for example, tsunami.

(E) Environment-friendly: does not introduce noise or extra material hazards, nor consumes extra energy. (F) Sustainable for long-term performance, convenience for maintenance.

(G) Convenience for fast construction, retrofit, and replacement.

(H) Cost-effectiveness.

Summary of the invention

This invention discloses a class of apparatuses, termed“V-Shaped Connector”, in short, “V-Connector”. Featured by its simplicity and practical feasibility for engineering applications, said V-Connector can be used to connecting units within a engineering structure such as a bridge or a building, or a machine, to satisfy the criteria (A) to (H) addressed previously, wherein said unit is a structural component of said engineering structure. The basic embodiment of said V- Connector and its variations are explained by Figs la to ld. Each V-connector is an assembly that comprises at least two of the following basic elements: (i) V-shape guiding tubes (VGT) that is a V-shaped tube of a chunk of solid with a v-shaped cavity, see Figs la and lb; wherein said VGT is mounted or embedded into one of said connected unit-pair in a machine or in a civil engineering structure. In Figs la to ld the connected unit-pair includes a bridge’s beam and a pier; (ii) a stabilization-pin, abbreviation“SBP”; examples of SBP are plotted in Figs. 2a and 2b; wherein at least one end of said SBP is inserted into said VGT; (iii) an optional damping cone that is filled in said VGT around said SBP inserted; (iv) an optional top bearing pad that is mounted onto one unit of the connected unit-pair; and an optional bottom bearing pad that is mounted onto another unit; (v) an optional washer that is between the contacted surface-pair of said two connected structural unit-pair; said surface-pair is the pair of contacted surfaces of top and bottom bearing pads if they are adopted by a V-Connector. The family of V-Connectors can be divided into two subclasses: Double-V Connector and Single-V Connector, wherein by the former each V-connector comprises two VGTs, see Figs la and lb, whereas by the latter each V-Connector comprises only one VGT;”, see Figs lc and ld, which can be further divided into at least two subgroups. One subgroup is that one end of SBP is hinged onto another structural component and thus it is with the flexibility of rotation, termed“Hinged-End Pin V-Connector” and, by abbreviation,“HPV”; another subgroup is that one end of said SBP is attached onto the component without the flexibility of rotation, or said SBP is a part of the component’s matrix; this subgroup is termed“Fixed-Pin V-Connector” and, by abbreviation,“FPV”; wherein said component can be an element of the V-Connector, for example, the top or bottom bearing pad, or one unit of the connected unit-pair.

Utilizing a pin to connect two structural parts, while restricting lateral relative motion in- between, is a common method by engineering designs. For a structure with seismic resistant requirement, pins are often adopted to reinforce structural integrity, for example, the conventional shear-key in bridges. By the author’s best knowledge that the design with combined pin and V-shaped guiding cavity(ies) by V-connector is different from all pin and pin-like connectors so far in applications; this is because, by the latter, one end of a pin is either (i) embedded into one unit of connected unit-pair, or, (ii) inserted into a cavity of the unit’s matrix closely or with very limited proximity, e.g. Dowel Pin, or, (iii) in open space to restrict an unit’s motion along a designated direction, e.g. shear key; another end of the pin is either (i) a convex portion of another unit’s matrix of the connected unit-pair, or, (ii) embedded or insert into a cavity of the another unit without proximity. These kinds of pin-connectors either lack of the ductility needed for seismic isolation or are not able to restore original state after impacted by strong dynamic loads. Though providing robust connection, applicability is very limited for the pin-connector group, such as Dowel Pin, for a structure such as the connection between a long- span beam and two piers due to the extra requirements to accommodate construction tolerance and thermal -induced expansion and shrinkage.

Hence, the primary innovative charactor of the V-connector is the design combination of the stabilization pin (SBP) and V-shaped cavity in said V-shape guiding tubes (VGT). The V- shape cavity has the length Lc part with V-shape crater-like geometry and the length Lt part that is with the same sectional -geometry as the inserted SBP, see Fig. la. This crater-like geometry of the length Lc part enables practically-needed self-centering to guide a pin to be inserted into the length Lt part of the VGT, so as to connect two structural units. The length Lt part holds said SBP tight to assure the connection’s robustness. On the other hand, the cross-sectional geometry and perimeter of the SBP are variable, see Fig. 2, which, in conjunction with the curvature of the length Lc part of a VGT, are designed to assure the robust connection of the V-Connector while be able to perform desired nonlinear hysterical behavior as an isolation bearing does, which is achieved by gradually-elevated resistance to lateral motion through smoothly-increased contact between the pin and the wall of VGT, as illustrated in Fig. 3. By this figure one can see that the friction between the contact surface-pair of two connected parts, with or without the washer in Figs la-lc, resulted in energy dissipation when a relative lateral motion occurs between the two connected units and producing desired ductility as characterized by the hysterical curve illustrated in Fig. 3(c). The combination of VGT and SBP, which allows confined relative sliding between connected parts while utilizing weight-induced natural friction as dissipation mechanism, is the center of the disclosed invention.

Though multiple pins may be used to connect two structural parts, sufficient strength and toughness are the obvious crucial requirement for each said SBP, for which modern high- strength alloys can be a candidates-pool to make it. However, the strength and Young’s module of steel or other metals are generally one to two orders higher than concrete. Simply insert such a pin into the V-shaped cavity within a concrete matrix may cause localized damage, for example, the concrete around the end of pin. These highlight the innovative feature of the V-shape guiding tube (VGT) in Figs la-lc. It smears out possible stress concentration caused by the pin without compromise of the functions associated with the cavity’s geometry. The guiding tube can be made of regular steel, or composite, e.g. Teflon, pre-casted into connected concrete part with an attached reinforcement ring to assure robustness with the matrix. Obviously, under the following circumstances: (i) the concrete has sufficient strength or the matrix is other kind of high-strength material; (ii) the pin’s diameter is large enough so the result stress concentration is ignorable, VGT is also optional when a cavity with the same geometries can be made within the matrix of a connected part.

Additional dissipation can be achieved by inserting a damping cone between SBP and VGT, see Fig. la. The damping cone is made of the material with visco-liquidity, e.g. lead or filled by silicon powders or sands; a part of the cone will be squeezed away when the pin deforms towards tube’s wall; some of these elements will be squeezed back again once the pin is vibrated to opposite direction. This process dissipates involved vibration energy while shifts the structure’s natural frequency away from resonation frequency, adding additional dissipation to the process explained in Fig. 3.

The basic concept for the embodiments described in Figs la-ld is originated from the previous art“PCT/US2012/0613127 [16]”, see Fig. 4. In the article [16] the V-geometry has been used to confine the relative separation of a class of new seismic isolation bearings with sliding-pin, i.e. the device (2) in the figure; whereas another class of new bearings (3) in the figure, utilizes bar to enforce vertical constraint of the elastomeric bearings with flat and V- geometry, respectively.

The benefit of the V-connector is not only to reduce the risk of resonated vibration without the need of additional mass, it actually also improves the stress state in connected structural parts if they are made of concrete. It is well-known that many non-metal materials, such as concrete, have strong compression strength but with very limited capacity against tension stress. This is the reason that significant amount of steel rebar have to be embedded into body of concrete. When a concrete column is under bending, the steel rebars on tension side takes almost 100% of tension load while the concrete surrounding rebars just plays the role to assure stability. It has been often observed that persistent shocks during an earthquake eventually caused concrete spalling that results in embedded steel bars’ bowing. By contract, an advantage by the V-connector is that this system transfers the tension zone in CIP structure into the compression zone around VGT. However, as illustrated by the plot on the left most in Fig. 5, on the plane between the two connected parts contact surface-pair, shear stress reaches maximum. This is the reason for the design options (c) in Fig. 2, i.e. the SBP with enlarged cross-sectional outline at middle part. The right of Fig. 5 introduces a solution for this purpose: to add shear reinforce V- ring (SRV), by which the advantage is easy to manufacture.

Besides the connection between a bridge’s beam and pier, the apparatuses family disclosed by this article can also be used as the connectors between pier and spreading footing, Fig. 6, as well as that between factory-manufactured floor-units in buildings, Fig. 7. Experimental Verifications

Although vibration mitigation and structure’s seismic-proof design involve many complicated factors, for engineering applications the basic principle [4-6] can be explained by Fig. 8. On right of the figure is an earthquake-spectrum diagram for a construction site where a structure is supposed to be built. The inertia force caused by an earthquake is proportional the peak ground acceleration (PGA) that can be calculated according this earthquake spectrum diagram if the self-vibration period T for the first order natural frequency of the structure is known; whereby the T can be approximated by the formula on the left-low corner of Fig. 8, which is proportional to the square-root of the structure’s weight and inversely proportional to the square-root of the structure’s global stiffness K , i.e. when K is smaller, T is longer, so the PGA will be lower according the spectrum curve in the diagram. Hence, the principle to increase a structure’s survivability against strong earthquakes is to increase the ductility of the structure. This is because, when the structure is struck by an earthquake, its distortion-resulted internal force should not be linearly proportional to the earthquake-induced distortion, expressed as the relationship between lateral force and lateral displacement. Under regular load condition, such a force-displacement relationship is linear, characterized by a structure’s stiffness K_e , see the plot on the left-high corner of Fig. 8. For a seismic-proof structure, a nonlinear force-displacement relationship is expected, which is termed structural ductility and can be characterized by the effective stiffness K_eff , the slope of the diagonal line for the hysteric loop on the left-high of Fig. 8. This is the reason for the innovative concept of V-connector’s design to obtain the hysterical cycles in Fig. 3. The experimental verification of the V-Connector has been conducted simultaneously in the Heng-Shui Earthquake Research Lab. of Heibei Province, China and in the PEER Lab. (Pacific Earthquake Engineering Research Center) at ETniversity of Berkeley, United States. Fig. 9 shows the laboratory setup and two manufactured specimen sets of HPSV, the Hinged-Pin Single-V Connector. Fig. 10 shows the test machine. Figs 11 and 12 are the measured hysterical curves of the test, which agree with the predicted curve-type in Fig. 3 and proof the capability of the V-connector for the function of earthquake protection.

Claims

Claims:

1) A class of apparatuses and a method to utilize said apparatus to join a pair of units, referred by a “unit-pair” thereof, together in a structural system, which provides robust connection while allows confined relative sliding between said unit-pair when said structural system is struck by strong external dynamic loads, wherein said structural system is a machinery system or a civil engineering construction such as a building or a bridge, wherein said unit is one among the group of major structural components in said structural system, wherein said major structural component is the component that carries major force-flow of said structural system and transfers the force-flow to at least another one connected major structural component or through the boundary of said structural system to other mediums in environment, wherein said major force-flow is caused by said major structural components’ weights and all of other loads carried by said structural system.

Said apparatus comprises at least one stabilization pin, referred by the abbreviation“pin” thereof, wherein the geometries and sizes of said pin’s cross-sections perpendicular to its axis are varying along the direction of said axis, wherein said axis is referred as“pin’s axis” thereof, which coincides to the direction along which said pin has the length that is longer than the size along any other direction; wherein the first end of said pin is attached onto a surface of a unit’s matrix of said unit- pair through a method selected from the group that includes welding, bolting, or casting, wherein the unit is referred as“the first unit” of said unit-pair thereof, wherein the surface of the first unit’s matrix with attached said pin is referred as“the first connecting surface” thereof.

Said method comprises two steps; wherein the first step is to pre-cut or precast at least one cavity onto a surface of another unit’s matrix of said unit-pair, wherein the unit is referred as the second unit’s matrix thereof; wherein the surface is referred as“the second connecting surface” thereof, wherein said cavity has an axis along which the size of said cavity is larger than its size along any other direction, this axis is referred as“cavity’s axis” thereof, wherein said cavity’s axis is not parallel to the second connecting surface, wherein said cavity comprises a“length-/. part” that has the length Lt along said cavity’s axis and a“length-Zc part” that has the length Ac along said cavity’s axis, wherein the sum of Lt and Lc is greater than the length of said pin along said pin’s axis, wherein said length-/._/ part starts from said cavity’s bottom and is with the inner cross sectional- geometry that matches the cross sectional-geometry of a part of said pin starts from the second end when said cavity’s axis is parallel to said pin’s axis, wherein said pin can be inserted into said length-/._/ part of said cavity without proximity along the direction perpendicular to said cavity’s axis, wherein said length-Zc part of said cavity is designed to have a crater-shaped geometry with its opening towards to the second connecting surface.

The second step of said method is to connect said unit-pair through inserting the second end of said pin into said cavity while assuring the first connecting surface and the second connecting surface contact each other, so the first connecting surface becomes a contact surface, referred as“the first contact surface” thereof, and the second connecting surface becomes another contact surface, referred as“the second contact surface” thereof; when said unit-pair is connected, the first contact surfaces and the second contact surfaces contact each other, referred as“contact surface-pair” thereof.

2) The apparatus and a method to utilize said apparatus to join a pair of units in claim 1, wherein said apparatus comprises at least one top bearing pad that is mounted onto the first unit of said unit-pair by one surface of said top bearing pad attached to the first connecting surface, so another surface of said top bearing pad becomes the first contact surface of said contact surface-pair when said unit- pair is connected.

3) The apparatus and a method to utilize said apparatus to join a pair of units in claim 1, wherein said apparatus comprises at least one top bearing pad, wherein the first end of said pin is hinged onto said top bearing pad with the flexibility of rotation but can not be removed from the pad, wherein said top bearing pad is mounted onto the first unit of said unit-pair by one surface of said top bearing pad attached to the first connecting surface, so another surface of said top bearing pad becomes the first contact surface of said contact surface-pair when said unit-pair is connected.

4) The apparatus and a method to utilize said apparatus to join a pair of units in claim 1, wherein said apparatus comprises at least one top bearing pad, wherein the first end of said pin is fixed onto said top bearing pad without the flexibility of rotation but can not be removed from the pad, wherein said top bearing pad is mounted onto the first unit of said unit-pair by one surface of said top bearing pad attached to the first connecting surface, so another surface of said top bearing pad becomes the first contact surface of said contact surface-pair when said unit-pair is connected.

5) The apparatus and a method to utilize said apparatus to join a pair of units in claim 1, wherein said apparatus comprises at least one bottom bearing pad that is mounted onto the second unit of said unit-pair by one surface of said bottom bearing pad attached to the second connecting surface, so another surface of said bottom bearing pad becomes the second contact surface of said contact surface-pair when said unit-pair is connected.

6) The apparatus and a method to utilize said apparatus to join a pair of units in claim 1, wherein said pin has the geometries and sizes perpendicular to said pin’s axis are not varying along the direction of said pin’s axis.

7) The apparatus and a method to utilize said apparatus to join a pair of units in claims 1 to 6, wherein said apparatus comprises at least one washer that is in-between the first contact surface and the second contact surface of said contact surface-pair.

8) A class of apparatuses and a method to utilize said apparatus to join a pair of units, referred by a “unit-pair” thereof, together in a structural systemg, which provides robust connection while allows confined relative sliding between said unit-pair when said structural system is struck by strong external dynamic loads, wherein said structural system is a machinery system or a civil engineering construction such as a building or a bridge, wherein said unit is one among the group of major structural components in said structural system, wherein said major structural component is the component that carries major force-flow of said structural system and transfers the force-flow to at least another one connected major structural component, wherein said major force-flow is caused by said major structural components’ weights and all of other loads carried by said structural system.

Said apparatus comprises

at least one stabilization pin, referred by the abbreviation“pin” thereof,

at least one V-shape guiding tube, refereed by the abbreviation“tube” thereof,

wherein the geometries and sizes of said pin’s cross-sections perpendicular to its axis are varying along said axis, wherein said axis is referred as“pin’s axis” thereof, which coincides to the direction along which said pin has the length that is longer than the size along any other direction; wherein the first end of said pin is attached onto a surface of a unit’s matrix of said unit-pair through a method selected from the group that includes welding, bolting, or casting, wherein the unit is referred as“the first unit” of said unit-pair thereof, wherein the surface of the first unit’s matrix with attached said pin is referred as“the first connecting surface” thereof;

wherein said tube comprises an opened cavity, referred as“cavity” thereof, wherein said cavity has an axis along which the size of said cavity is larger than its size along any other direction, this axis is referred as“cavity’s axis” thereof, wherein said cavity comprises a“length-/. part” that has the length Lt along said cavity’s axis and a“length-Zc part” that has the length Lc along said cavity’s axis, wherein the sum of Lt and Lc is greater than the length of said pin along said pin’s axis, wherein said length-/._/ part starts from said cavity’s bottom and is with the inner cross sectional- geometry that matches the outer cross sectional-geometry of the part of said pin starts from the second end when said cavity’s axis is parallel to said pin’s axis, wherein said pin can be inserted into said length-Z_ί part of said cavity without proximity along the direction perpendicular to said cavity’s axis, wherein said length-Zc part of said cavity is designed to have a crater-shaped geometry towards to its opening, which allows confined flexural deformation of said pin.

Said method comprises two steps; wherein the first step is to pre-cut or precast at least one cavity onto a surface of another unit’s matrix of said unit-pair, wherein the cavity is referred as“matrix’ cavity” thereof, wherein the surface is referred as“the second connecting surface” and the unit is referred as“the second unit” thereof, wherein said matrix’ cavity has the same geometry and size as the outer geometry and size of said tube so the tube can be inserted into said matrix’ cavity without proximity while the open of said tube’s cavity is on the second connecting surface. The second step of said method is to connect said unit-pair through inserting the second end of said pin into said cavity of said tube while assuring the first connecting surface and the second connecting surface contact each other, so the first connecting surface becomes a contact surface, referred as“the first contact surface” thereof, and the second connecting surface becomes another contact surface, referred as“the second contact surface” thereof; when said unit-pair is connected, the first contact surfaces and the second contact surfaces contact each other, which is referred as “contact surface-pair” thereof.

9) The apparatus and a method to utilize said apparatus to join a pair of units in claim 8, wherein said apparatus comprises at least one top bearing pad that is mounted onto the first unit of said unit-pair by one surface of said top bearing pad attached to the first connecting surface, so another surface of said top bearing pad becomes the first contact surface of said contact surface-pair when said unit- pair is connected.

10) The apparatus and a method to utilize said apparatus to join a pair of units in claim 8, wherein said apparatus comprises at least one top bearing pad, wherein the first end of said pin is hinged onto said top bearing pad with the flexibility of rotation but can not be removed from the pad, wherein said top bearing pad is mounted onto the first unit of said unit-pair by one surface of said top bearing pad attached to the first connecting surface, so another surface of said top bearing pad becomes the first contact surface of said contact surface-pair when said unit-pair is connected.

11) The apparatus and a method to utilize said apparatus to join a pair of units in claim 8, wherein said apparatus comprises at least one top bearing pad, wherein the first end of said pin is fixed onto said top bearing pad without the flexibility of rotation but can not be removed from the pad, wherein said top bearing pad is mounted onto the first unit of said unit-pair by one surface of said top bearing pad attached to the first connecting surface, so another surface of said top bearing pad becomes the first contact surface of said contact surface-pair when said unit-pair is connected. 12) The apparatus and a method to utilize said apparatus to join a pair of units in claim 8, wherein said apparatus comprises at least one bottom bearing pad that is mounted onto the second unit of said unit-pair by one surface of said bottom bearing pad attached to the second connecting surface, so another surface of said bottom bearing pad becomes the second contact surface of said contact surface-pair when said unit-pair is connected.

13) The apparatus and a method to utilize said apparatus to join a pair of units in claim 8, wherein said pin has the geometries and sizes perpendicular to said pin’s axis are not varying along the direction of said pin’s axis.

14) The apparatus and a method to utilize said apparatus to join a pair of units in claims 8 to 13, wherein said apparatus comprises at least one washer that is in-between the first contact surface and the second contact surface of said contact surface-pair.

15) A class of apparatuses and a method to utilize said apparatus to join a pair of units, referred by a “unit-pair” thereof, together in a structural system, which provides robust connection while allows confined relative sliding between said unit-pair when said structural system is struck by strong external dynamic loads, wherein said structural system is a machinery system or a civil engineering construction such as a building or a bridge, wherein said unit is one among the group of major structural components in said structural system, wherein said major structural component is the component that carries major force-flow of said structural system and transfers the force-flow to at least another one connected major structural component or through the boundary of said structural system to other mediums in environment, wherein said major force-flow is caused by said major structural components’ weights and all of other loads carried by said structural system.

Said apparatus comprises at least one stabilization pin, referred by the abbreviation“pin” thereof, wherein the geometries and sizes of said pin’s cross-sections perpendicular to its axis are varying along the direction of said axis, wherein said axis is referred as“pin’s axis” thereof, which coincides to the direction along which said pin has the length that is longer than the size along any other direction;

Said method comprises two steps; wherein the first step is to pre-cut or precast at least one cavity onto a surface of each unit’s matrix of said unit-pair, wherein the surface on the first unit is referred as“the first connecting surface” whereas the surface on the second unit is referred as“the second connecting surface”, wherein each said cavity has an axis along which the cavity’s size is larger than its size along any other direction, this axis is referred as“cavity’s axis” thereof, wherein each said cavity comprises a“length-Zi part” that has the length Lt along the cavity’s axis and a“length-Zc part” that has the length Lc along the cavity’s axis, wherein said length -Lt part starts from the cavity’s bottom and is with the inner cross sectional-geometry that matches the cross sectional-geometry of a part of said pin starts from one of its end when the cavity’s axis is parallel to said pin’s axis, wherein the end part of said pin can be inserted into said length -Lt part of the cavity without proximity along the direction perpendicular to the cavity’s axis, wherein said length-Zc part of the cavity is designed to have a crater-shaped geometry with its opening towards to the corresponding connecting surface.

The second step of said method to connect said unit-pair is first to insert the first end of said pin into the cavity on the first connecting surface of the first unit and then to move the second unit towards to the first unit let the second end of said pin to be inserted into the cavity on the second connecting surface while assuring the first connecting surface and the second connecting surface contact each other, so the first connecting surface becomes a contact surface, referred as“the first contact surface” thereof, and the second connecting surface becomes another contact surface, referred as“the second contact surface” thereof; when said unit-pair is connected, the first contact surfaces and the second contact surfaces contact each other, referred as“contact surface-pair” thereof.

16) The apparatus and a method to utilize said apparatus to join a pair of units in claim 15, wherein said apparatus comprises at least one top bearing pad that is mounted onto the first unit of said unit-pair by one surface of said top bearing pad attached to the first connecting surface, so another surface of said top bearing pad becomes the first contact surface of said contact surface-pair when said unit- pair is connected.

17) The apparatus and a method to utilize said apparatus to join a pair of units in claim 15, wherein said apparatus comprises at least one top bearing pad, wherein the first end of said pin is hinged onto said top bearing pad with the flexibility of rotation but can not be removed from the pad, wherein said top bearing pad is mounted onto the first unit of said unit-pair by one surface of said top bearing pad attached to the first connecting surface, so another surface of said top bearing pad becomes the first contact surface of said contact surface-pair when said unit-pair is connected.

18) The apparatus and a method to utilize said apparatus to join a pair of units in claim 15, wherein said apparatus comprises at least one top bearing pad, wherein the first end of said pin is fixed onto said top bearing pad without the flexibility of rotation but can not be removed from the pad, wherein said top bearing pad is mounted onto the first unit of said unit-pair by one surface of said top bearing pad attached to the first connecting surface, so another surface of said top bearing pad becomes the first contact surface of said contact surface-pair when said unit-pair is connected.

19) The apparatus and a method to utilize said apparatus to join a pair of units in claim 15, wherein said apparatus comprises at least one bottom bearing pad that is mounted onto the second unit of said unit-pair by one surface of said bottom bearing pad attached to the second connecting surface, so another surface of said bottom bearing pad becomes the second contact surface of said contact surface-pair when said unit-pair is connected. 20) The apparatus and a method to utilize said apparatus to join a pair of units in claim 15, wherein said pin has the geometries and sizes perpendicular to said pin’s axis are not varying along the direction of said pin’s axis.

21) The apparatus and a method to utilize said apparatus to join a pair of units in claims 15, wherein said apparatus comprises at least one washer that is in-between the first contact surface and the second contact surface of said contact surface-pair.

22) The apparatus and a method to utilize said apparatus to join a pair of units in claim 15, wherein said apparatus comprises at least one V-shaped guiding tube, referred as“VGT” thereof, wherein said VGT comprises a cavity with at least one open on said VGT’s surface, wherein said cavity is referred as“VGT’s cavity” thereof, wherein the plane coincides to the open of said VGT’s cavity is referred as“open plane of VGT’s cavity” thereof, wherein said VGT’s cavity has an axis along which the cavity’s size is larger than the size along any other direction, wherein said axis is referred as“axis of VGT’s cavity” thereof, wherein said VGT’s cavity comprises a“length-/. part” that has the length Lt along the axis of VGT’s cavity and a“length-Zc part” that has the length Zc along the axis of VGT’s cavity, wherein said length-/.- part starts from the VGT’s cavity’s bottom and is with the inner cross sectional-geometry that matches the cross sectional -geometry of one end part of said pin when the axis of VGT’s cavity is parallel to said pin’s axis, wherein the end part of said pin can be inserted into said length-/. part of the VGT’s cavity without proximity along the direction perpendicular to the axis of VGT’s cavity, wherein said length-Zc part of the VGT’s cavity is designed to have a crater-shaped geometry with said VGT’s surface.

23) The apparatus and a method to utilize said apparatus to join a pair of units in claims 15 and 22, wherein the first step of said method is to pre-cut or precast at least one cavity onto at least one unit’s surface of said unit-pair, wherein said cavity is referred as“unit’s cavity” thereof and wherein said surface is referred as“unit’s connecting surface” thereof, wherein said unit’s cavity has the same geometry and size as said VGT’s geometry and size has, so said VGT can be inserted into said unit’s cavity without proximity while said open plane of VGT’s cavity coincides to said unit’s connecting surface.