CN219175011U - Assembled prestressing force bent cap platform of encorbelmenting - Google Patents

Abstract

The utility model provides an assembled prestress bent cap overhanging platform, which belongs to the technical field of bent cap construction and comprises a pier body, a shear bar, a bent cap body and a bent cap overhanging bracket, wherein the upper end of the pier body is fixedly connected with the bent cap body, the interior of the pier body penetrates through the shear bar, temporary supports are detachably connected to the exterior of the pier body, two groups of bent cap overhanging brackets are arranged on two sides of the pier body and are symmetrically distributed on the two sides of the pier body, the two groups of bent cap overhanging brackets are connected through high-strength bolts, the bent cap overhanging bracket comprises a main beam, an auxiliary beam, a main diagonal brace, an auxiliary diagonal brace and an outer platform tripod, the main beam is detachably arranged on the temporary supports, a plurality of outer platform tripods are detachably arranged on the outer side of the main beam, and the auxiliary beam is detachably arranged on the two ends of the main beam; the cantilever length of the bearing beam can be increased, the high requirement of the rectangular column pier prestress bent cap on the bending-resistant bearing capacity of the I-steel bearing beam can be met, and the technical problem that the traditional attached overhead bracket method cannot meet the construction requirement of the prestress bent cap is solved.

Description

Assembled prestressing force bent cap platform of encorbelmenting

Technical Field

The utility model relates to an assembled prestress bent cap overhanging platform, which is not limited to the utility model.

Background

In highway bridge engineering in valley mountain areas, the pier column height is often designed to be higher due to large relief height difference, the rectangular column type pier bent cap is usually constructed by adopting an attached overhead support method (comprising a hoop method support, a shear bar method support and a pre-buried steel plate method support), but the traditional attached overhead support method construction uses an I-shaped steel beam as a spandrel girder, and the deflection of the cantilever parts at two ends of the bearing beam gradually becomes larger along with the increase of the length of the cantilever parts at two ends of the bearing beam, so that the requirement on the bending moment value at two ends of the bearing beam is higher. If the overhanging length of the bearing cross beam is not increased, the requirement of the rectangular column pier prestress bent cap on the length of the transverse construction platform cannot be met, and if the overhanging length of the bearing cross beam is increased, the requirement of the rectangular column pier prestress bent cap on the high bending resistance bearing capacity of the I-steel bearing cross beam cannot be met. If the steel tube column type overhead support platform is adopted for installation and construction, the problem of insufficient bending bearing capacity of the large-span I-steel bearing cross beam can be effectively solved, but compared with the attached overhead support method, the following defects exist: 1. has higher requirement on the bearing capacity of the foundation. 2. The stand column and the concrete foundation of the floor need to occupy a certain space. 3. The capping beam has higher ground clearance and poor economy. 4. The installation procedure is complicated. 5. The erection period is long and the turnover period is long.

Disclosure of Invention

The utility model provides an assembled pre-stress bent cap overhanging platform, which aims to solve the technical problem that the traditional attached overhead bracket method cannot meet the construction requirement of a pre-stress bent cap.

In order to achieve the above purpose, the present utility model adopts the following technical scheme:

the utility model provides an assembled prestressing force bent cap platform of encorbelmenting, includes pier shaft, shear force stick, bent cap body and bent cap support of encorbelmenting, pier shaft upper end fixed connection bent cap body, run through the shear force stick in the pier shaft, the pier shaft outside is detachably connected with temporary support, the support of encorbelmenting is provided with two sets of, and the symmetric distribution is in pier shaft both sides, the support of encorbelmenting of bent cap includes main crossbeam, auxiliary crossbeam, main bracing, auxiliary bracing and outer platform tripod, main crossbeam demountable installation is in on the temporary support, the outside of main crossbeam still demountable installation has a plurality of outer platform tripod, the both ends demountable installation of main crossbeam has auxiliary crossbeam;

the main diagonal brace is fixedly connected with the main diagonal brace, the main cross beam is detachably connected with the main diagonal brace, the main cross beam and the main diagonal brace enclose an inverted trapezoid, and the main diagonal brace, the main cross beam and the secondary diagonal brace are detachably connected through bolts.

As a further description of the above technical solution:

the two groups of cantilever brackets of the bent cap are connected through high-strength bolts.

As a further description of the above technical solution:

the main beam and the auxiliary beam are internally penetrated by finish rolling deformed steel bars, and the main beam and the auxiliary beam are fixed by means of finish rolling deformed steel bars in opposite pulling.

As a further description of the above technical solution:

the temporary support comprises channel steel and sand boxes, the channel steel is tightly attached to the pier body, the notch is upwards erected on two shear bars on one side of the pier body, the sand boxes are symmetrically arranged above two sides of the channel steel, sand is filled in the sand boxes, and the center of the temporary support and the center of a shear bar connecting line are on the same vertical line.

As a further description of the above technical solution:

the auxiliary beam lengthening cantilever structure is detachably arranged at one end, far away from the main beam, of the auxiliary beam.

As a further description of the above technical solution:

the auxiliary cross beam and the auxiliary cross beam lengthening cantilever structure are fixedly connected with distribution beams, the upper ends of the distribution beams are detachably connected with construction channels through U-shaped fasteners, and the construction channels are assembled construction channels.

As a further description of the above technical solution:

the shear bar is a 45# shear bar with the diameter of 16cm, the length of 6m and the weight of 4.8 t.

The utility model has the beneficial effects that:

the cantilever bracket of the bearing bent cap above the shear bar adopts an assembly cantilever bracket technology, a main beam, an auxiliary beam, a main diagonal brace, a secondary diagonal brace and an outer platform tripod which are made of section steel are used as units, each unit is independently installed, and each unit is connected into a whole by adopting a high-strength bolt. The outer platform tripod arranged on the outer side of the main beam replaces the I-steel distribution beams on two sides of the pier body, and the problem that the I-steel distribution beams on the pier body are difficult to mount can be effectively solved. The auxiliary cross beam increases the length of the whole support structure, the main diagonal bracing and the auxiliary diagonal bracing structure provide effective support while guaranteeing the length of the support structure, the whole bending resistance bearing capacity of the support is guaranteed, and the whole stability of the support is improved. Therefore, the cantilever length of the bearing beam can be increased, and the high requirement of the rectangular column pier prestress bent cap on the bending bearing capacity of the I-steel bearing beam can be met, so that the technical problem that the traditional attached overhead bracket method cannot meet the construction requirement of the prestress bent cap is solved.

Drawings

In order to more clearly show an assembled pre-stressed bent cap overhanging platform, the following figures are shown;

FIG. 1 is a front view of a pier body capping beam body of the present utility model;

FIG. 2 is a top view of the pier body capping beam body of the present utility model;

FIG. 3 is a front view of the present utility model;

FIG. 4 is a top view of the present utility model;

FIG. 5 is a side view of the present utility model;

fig. 6 is a flow chart of the construction process of the present utility model.

Wherein reference numerals in the drawings;

1. a bent cap body; 2. a main beam; 3. an auxiliary cross beam; 4. a main diagonal brace; 5. a secondary diagonal bracing; 6. an outer platform tripod; 7. a distribution beam; 8. constructing a channel; 9. channel steel; 10. a pier body; 11. a sand box; 12. a shear bar; 13. finish rolling deformed steel bars; 14. the auxiliary cross beam lengthens the cantilever structure; 15. high strength bolts.

Detailed Description

Referring to fig. 1-6, fig. 1-6 respectively show an assembled pre-stress bent cap overhanging platform provided by the embodiment of the application, which comprises a pier body 10, a shear bar 12, a bent cap body 1 and a bent cap overhanging bracket, wherein the upper end of the pier body 10 is fixedly connected with the bent cap body 1, the interior of the pier body 10 penetrates through the shear bar 12, temporary supports are detachably connected to the exterior of the pier body 10, two groups of the bent cap overhanging brackets are arranged on two sides of the pier body 10 and symmetrically distributed, the two groups of the bent cap overhanging brackets are connected through high-strength bolts 15, the bent cap overhanging bracket comprises a main beam 2, an auxiliary beam 3, a main diagonal brace 4, a secondary diagonal brace 5 and an outer platform tripod 6, the main beam 2 is detachably arranged on the temporary supports, a plurality of outer platform tripods 6 are detachably arranged on the outer side of the main beam 2, and two ends of the main beam 2 are detachably provided with auxiliary beams 3;

the main diagonal bracing 4 is fixedly connected with the main diagonal bracing 4, the main cross beam 2 is detachably connected with the main diagonal bracing 4, the main cross beam 2 and the main diagonal bracing 4 enclose an inverted trapezoid, and the main diagonal bracing 4, the main cross beam 2 and the secondary diagonal bracing 5 are detachably connected through bolts.

Specifically, a bearing bent cap cantilever bracket above a shear bar 12 adopts an assembly cantilever bracket technology, a main beam 2, an auxiliary beam 3, a main diagonal brace 4, a secondary diagonal brace 5 and an outer platform tripod 6 which are made of profile steel are used as units, each unit is independently installed, and each unit is connected into a whole by adopting a high-strength bolt. The outer platform tripod 6 arranged on the outer side of the main beam 2 replaces the I-steel distribution beams 7 on the two sides of the pier body 10, and the problem that the I-steel distribution beams 7 on the position of the pier body 10 are difficult to erect can be effectively solved. The length of the whole support structure is increased by the auxiliary cross beam 3, the main diagonal bracing 4 and the auxiliary diagonal bracing 5 are used for guaranteeing the length of the support structure and simultaneously providing effective support, the whole bending resistance bearing capacity of the support is guaranteed, and the whole stability of the support is improved. Therefore, the cantilever length of the bearing beam can be increased, and the high requirement of the rectangular column pier prestress bent cap on the bending bearing capacity of the I-steel bearing beam can be met, so that the technical problem that the traditional attached overhead bracket method cannot meet the construction requirement of the prestress bent cap is solved.

The utility model adopts the 'assembled cantilever bracket' technology, thereby reducing the number of people in high-altitude operation and the high-altitude operation time, greatly improving the common fault of construction quality and improving the working efficiency and the overall stability.

As a further embodiment of the above technical solution:

the main beam 2 and the auxiliary beam 3 are internally penetrated with finish rolling screw thread steel 13, and the main beam 2 and the auxiliary beam 3 are fixed by accurate binding screw thread steel, so that the overhead working time can be reduced, the welding and binding times of the stress beam and the distribution beam 7 and the influence of other factors on the mounting quality of the stress bracket are avoided, and the overall stability of the cantilever bracket is improved.

As a further embodiment of the above technical solution:

the temporary support comprises channel steel 9 and sand boxes 11, the channel steel 9 is tightly attached to the pier body 10, the notch is upwards erected on two shear bars 12 on one side of the pier body 10, the sand boxes 11 are symmetrically arranged above two sides of the channel steel 9, sand is filled in the sand boxes 11, and the center of the temporary support and the center of a connecting line of the shear bars 12 are on the same vertical line.

The utility model also simplifies the temporary support installation process by adopting the technology of 'quick installation of the temporary support', shortens the time for installing the temporary support, improves the installation accuracy of the temporary support, and can effectively adjust the whole height of the cantilever support by using the sand box 11 as the temporary support so as to facilitate the dismantling of the capping beam bottom die.

As a further embodiment of the above technical solution:

the auxiliary beam lengthening cantilever structure 14 is detachably arranged on the auxiliary beam 3 at one end far away from the main beam 2, and the auxiliary beam lengthening cantilever structure 14 arranged at the end part of the auxiliary beam 3 can effectively increase the space of a construction operation platform and solve the problem of small space of the operation platform.

As a further embodiment of the above technical solution:

the upper ends of the auxiliary cross beam 3 and the auxiliary cross beam lengthening cantilever structure 14 are fixedly connected with a distribution beam 7, the upper end of the distribution beam 7 is detachably connected with a construction channel 8 through a U-shaped fastener, and the construction channel 8 is an assembled construction channel 8.

The construction channel 8 above the cantilever bracket of the bent cap adopts the 'fabricated construction channel 8 technology', the channel is formed by assembling all steel structures, the units such as a bottom frame, a movable cover plate, a guardrail net, an outlet guardrail, a corner platform and the like are mainly constructed by adopting a welding process, and an independent maintenance system is constructed outside the construction channel. Each unit is connected and fixed by adopting a matched bolt, the assembled platform is hung on a distribution beam which is about 30 centimeters away from the template position by using a crane through a hanging hook reserved on a platform bottom frame, and after the assembled platform is placed, the assembled platform is fixed by using a U-shaped fastener matched with a product to pass through a round hole reserved on a channel frame and the distribution beam. According to the construction environment, a special corner platform can be installed in different places, so that the construction working face is enlarged, and after the channel platform is installed, the bent cap safety barrier is installed on the connecting hole at the tail end of the bent cap channel platform.

As a further embodiment of the above technical solution:

the shear bar 12 was a 45# shear bar 12 having a diameter of 16cm, a length of 6m, and a weight of 4.8 t.

Working principle:

the following provides a specific construction process flow and operation points in combination with the content of the utility model:

as shown in fig. 6, the first step is to pre-embed pvc pipes, whose operation points are: when the pier column is constructed to be at a position which is away from the designed top elevation and only the last bin of concrete is required to be poured, the PVC pipe with the diameter of 20cm is embedded in the pier column along the bridge direction, the center of the embedded pipe is 145cm away from the bottom of the cover beam, the distance from the edge of the pier body 10 is 30cm, the embedded length is as wide as the pier column, and one embedded pipe is respectively embedded left and right. In order to avoid entering the embedded PVC pipe when pouring concrete, the pipe orifice is wound and plugged by transparent adhesive tape before the embedded pipe is installed, the embedded pipe is fixed by horizontal ribs up and down by the PVC pipe, the horizontal ribs are welded on the main ribs adjacent to the two sides of the PVC pipe, and the main ribs cannot be burnt during welding. The steel bar encryption areas are arranged in the 3m distance from the pier top, the steel bars in the encryption areas are 10cm, the periphery of the pipe body is surrounded by the stirrups, and excessive disturbance to the pipe body can not be generated during concrete pouring, so that the embedded PVC pipe body is not reinforced.

The second step is to install the shear bar 12, namely to install the shear bar 12, and the operation key points are as follows: the shear bar 12 serves as a main load bearing member, bearing the entire load from above. According to the requirements of 3.1.9 of the steel structure design standard, structural members, connections and nodes are designed in a limit state of bearing capacity, so that a limit state method is adopted for checking calculation.

1, calculating a parameter load standard value;

a. gravity of freshly cast concrete, reinforced concrete or masonry: take on a value of 26KN/m ³ ；

b. The constructor and the construction material transport and stacking load are 1kPa;

c. the load generated by vibrating the concrete: the value is 2kPa;

d. impact load generated when pouring concrete is 2kPa;

e. template, support, bow member, scaffold severe: the value is 1kPa.

2 main material design index

a. Q235 steel:

flexural strength design f=215 Mpa;

shear strength design value fv=125 Mpa;

elastic modulus e=206×10 ³ Mpa。

b. 45# rebar:

tensile strength design value f=600 MPa;

yield strength design value fv=355 MPa.

3 load analysis calculation

a. Load zone division

Because the beam body part is supported on the pier top, the calculation load only considers the actually supported beam body part. In order to facilitate load calculation, the weight of the beam body is calculated according to the change of the cross section of the capping beam and the constant cross section. As shown in table 1, two areas divided into A, B were calculated.

TABLE 1 Beam section information Table

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4 area load calculation

The load carried by the different areas can be calculated from table 1.

Beam Duan Hezai bearing per unit area of bottom die in section a:

the dead weight of the concrete is as follows: nhA =26 KN/m3×15.83m 2/6.15m= 66.92KN/m2.

The template load is: nhA =1 KN/m2×8.8m/6.15m=1.43 KN/m2.

Beam Duan Hezai bearing per unit area of bottom die in section B:

the dead weight of the concrete is as follows: nhA =26 KN/m3×19.48m 2/6.2m= 81.69KN/m2.

The template load is: nhA =1 KN/m2×6.2m/6.2m=1 KN/m2.

5) Load combination

The load combinations taken from the road and bridge construction calculation manual, chapter 1.1.4, tables 8-4, calculate templates, arches and brackets, specify:

a. the bottom forms of beams, plates and arches and the supporting plates, arches, brackets calculate the bearing capacity:

1.3×fresh concrete, concrete or masonry weight+formwork, brackets, arches, scaffold weight+1.5×constructor, construction tool transport, stacking load+load by vibrating concrete+impact load by pouring concrete

b. The beams, plates and arch bottom forms and the support plates, arches, brackets calculate the stiffness:

heavy + forms, brackets, arches, scaffolding heavy of =1.3×freshly poured concrete, reinforced concrete or masonry

The area of the section A is provided with the following area load:

n bearing=1.3×66.92+1.43+1.5×1+2+2= 96.355 kN/square meter

Njust=1.3×66.92+1.43= 88.855 kN/square meter

The area load of the section B is as follows:

n bearing=1.3×81.69+1+1.5×1+2+2= 114.997 kN/square meter

Njust=1.3×81.69+1= 107.497 kN/square meter

And (3) establishing a model by using Midas/Civil, and carrying out finite element analysis to obtain the maximum combined stress of the 45# shear rod 12 as follows: sigma (sigma) _max ＝2.2MPa＜[σ]=501 MPa, so the 45# shear bar 12 strength design meets safety requirements.

Therefore, after the pier column top is disassembled, the 45# shear rod 12 is penetrated into the reserved hole by adopting crane cooperation, so that the exposed length of the two ends is ensured to be not less than 1.45m. The two ends of the embedded hole are filled with wedges to fix the shear bar 12 and prevent sliding.

The third step is to install the temporary support, its operation main points are:

1) Temporary support pre-compaction test

Because the shear bar 12 is subjected to a maximum combined stress of 2.2MPa, a press is used to progressively apply a load to the temporary support of 2.2MPa to determine if the reliability of the structure is satisfactory when the load is applied. As shown in table 2, the displacement and force values generated during the pressing process are recorded, and the corresponding load is obtained through p=a×σ, wherein a is the inner diameter area of the sand bearing concrete at the lower part of the temporary support, namely the actual contact sand area of the top core, and is 379940mm2.

Table 2 table of support compaction factor information

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2 temporary support mounting

A 36b channel steel 936b channel steel 9 with the length of 6m is 12m generally, symmetrical cutting notches of the channel steel 9 are horizontally arranged on two exposed shear bars 12 on one side of the pier column by adopting hot cutting, and the channel steel 9 and the pier body 10 are horizontally overlapped. The theoretical weight of the channel steel 9 is 53.466 kg/m, the calculated weight of the channel steel 9 is 320 kg, and in consideration of the fact that the channel steel 9 mainly bears vertical load, the dead weight of the channel steel 9 is large, and horizontal displacement is difficult to generate through field practice, the channel steel 9 is not reinforced, the channel steel 9 can be welded on the shear bar 12 due to the influence of other factors in the field, and the shear bar 12 cannot be burnt during welding. And measuring the vertical distance from the channel steel 9 to the top of the pier stud, subtracting the bottom die thickness of 10cm, the 14# I-steel distribution beam 714cm and the main beam of 270cm to obtain the height of the temporary support before stress, and adjusting the height of the temporary support before stress to be 1.1cm upwards so as to offset downward displacement generated by the load born by the temporary support. And filling the lower sand bearing cylinder according to the calculated height, marking the height outside the temporary support after filling, placing the temporary support in the channel steel 9 installed above the shear bar 12, and accurately centering the temporary support and the shear bar 12 to ensure that the center of the temporary support and the center of the shear bar 12 are on the same line.

The fourth step is the installation of an assembled cantilever bracket, and the concrete operation key points are as follows:

1 assembled overhanging support stress checking calculation

The assembled cantilever frame mainly comprises HN700 x 300 x 13 x 24 cross beams, I14I-steel longitudinal beams, main diagonal braces 4I40b, secondary diagonal braces 5I30a, and the like which are assembled, and the strength and the rigidity of the assembled cantilever frame are respectively checked by using MIDAS/Civil structural analysis software, so that the result is as follows.

a. I14I-steel checking calculation

The maximum combined stress of I14I-steel is: sigma (sigma) _ma x＝160.8MPa＜[σ]＝215MPa；

The maximum shear stress of I14I-steel is: τ _max ＝37.9MPa＜[τ]＝125MPa；

So the I14I-steel strength design meets the design requirement.

The maximum combined stress deformation of I14I-steel is: smax= 8.546mm < L/400=4300/400=10.75 mm;

so the I14I-steel rigidity design meets the safety requirement.

b. HN700 x 300 x 13 x 24 cross beam stress checking calculation

The maximum combined stress of the cross beam is as follows: sigma (sigma) _max ＝17.3MPa＜[σ]＝215MPa；

The maximum shear stress of the cross beam is as follows: τ _max ＝20.1MPa＜[τ]＝125MPa；

Therefore, the HN700 x 300 x 13 x 24 beam strength design meets the design requirements.

HN700 x 300 x 13 x 24 beam maximum combined stress deformation is: smax=0.289 mm < L/400=1159/400= 2.898mm;

therefore, HN700 x 300 x 13 x 24 beam stiffness design meets the safety requirements.

c. Main diagonal bracing 4I40b stress checking calculation

The maximum combined stress of the main diagonal bracing 4 is as follows: sigma (sigma) _max ＝23.5MPa＜[σ]＝215MPa；

The maximum shear stress of the main diagonal bracing 4 is as follows: τ _max ＝1.8MPa＜[τ]＝125MPa；

So the strength design of the main diagonal bracing 4I40b meets the design requirement.

The maximum combined stress deformation of the main diagonal brace 4I40b is: smax= 6.564mm < L/400=6000/400=15 mm;

so the rigidity design of the main diagonal bracing 4I40b meets the safety requirement.

d. Checking and calculating stress of secondary diagonal brace 5I30a

The maximum combined stress of the secondary diagonal bracing 5 is as follows: sigma (sigma) _max ＝34.3MPa＜[σ]＝215MPa；

The maximum shear stress of the secondary diagonal bracing 5 is as follows:

τ _max ＝14.1MPa＜[τ]＝125MPa；

the strength design of the secondary main diagonal bracing 4I30a meets the design requirement.

The maximum combined stress deformation of the secondary diagonal brace 5I30a is: smax= 6.564mm < L/400=6000/400=15 mm;

so the rigidity design of the main diagonal bracing 4I40b meets the safety requirement.

e. Precision rolling deformed steel bar 13 stress checking calculation

The maximum combined stress of the finish rolled deformed steel bar 13 is: sigma (sigma) _max ＝34.3MPa＜[σ]＝300MPa

The maximum tension of the finish rolled deformed steel bar 13 is 87.8N, sigma _{Pulling device} ＝F/A＝0.109MAa＜[σ]＝270MPa。

The strength design of the finish rolled deformed steel bar 13 meets the safety requirements.

f. Bolt anchoring stress calculation

Because the connecting plates are required to be arranged at the connecting positions in the splicing process of the templates, all the components are connected through the connecting plates by using bolts, the stress calculation is required to be carried out on the bolts of all the rod pieces, and only the most unfavorable positions of the components are calculated.

The maximum pulling force occurs at the connection position of the main diagonal bracing 4 and the secondary diagonal bracing 5, and the maximum pulling force is 41KN; the main diagonal bracing 4 and the secondary diagonal bracing 5 are connected by M2410.9-level split bolts, the longitudinal spacing is 20cm, and the vertical spacing is 20cm; the split bolt mainly bears the load transferred by the lateral template, and the tension applied to the pull rod is as follows: n bolts=41/6=6.8kn, n=0.02×0.02×6.8×1000=2.72N/mm 2, nbt =531×47.9×1000= 25434.9KN/mm2, N < Nbt, so the calculation of the tensile strength of the M24 pair of tie bolts meets the requirements.

2 mounting assembly type cantilever bracket

The overhanging support members are processed by a professional processing plant, and are assembled synchronously and integrally. The main beam 2, the auxiliary beam 3, the main diagonal brace 4 and the main diagonal brace 4 tripod are firstly installed at the respective parts. And the main beam 2 is assembled: the tripod structure is arranged on the perforated rib plate at the outer side of the main beam 2 and is fastened by adopting bolt connection. And the auxiliary cross beam 3 is assembled: the lengthened overhanging structure is assembled with the auxiliary beam 3, the end head of the auxiliary beam 3 is welded by adopting a 20mm flange, and the lengthened overhanging structure is fastened through bolt connection. The main diagonal bracing 4 and the main diagonal bracing 4 tripod are welded, and the end is provided with a flange and a bolt hole for connecting bolts. The assembled main and auxiliary beams 3, the main diagonal braces 4 and the triangular frames of the main diagonal braces 4 are fastened by adopting bolt connection, and the assembled whole beam and the diagonal braces are fastened by adopting bolt connection to form the cantilever spandrel girder. The two assembled cantilever spandrel girders are installed at the top of the temporary support in a mode of crane and manual cooperation, the prefabricated holes distributed on the cantilever spandrel girder main beam 2, the auxiliary beam 3 and the main diagonal bracing 4 are sequentially connected in a counter-pulling mode by adopting 30 finish rolling screw steel 13, so that the whole stress is uniform, and the stability is improved. After the cantilever spandrel girder is installed, the No. 14I-steel distribution beams 7300mm are uniformly distributed at the top of the cantilever spandrel girder, and the cantilever spandrel girder middle main beam 2 is not required to be provided with the I-steel distribution beam 7 in the range of 26m of the middle main beam due to the tripod structure extending for 1 m.

The fifth step is the installation of the assembly type construction channel 8, and the operation key points are as follows:

1 assembled construction channel 8 stress checking calculation

The assembled construction channel 8 mainly comprises channel platforms with different lengths, corner platforms and protection nets. The strength requirement on the platform is that the frame and the welding part are not damaged when the load of 6KN is uniformly distributed and the requirement on the protective net is 1 KN. Because the assembled construction platform is customized by a professional manufacturer and a product structure inspection book is provided, the concrete test is mainly based on whether the platform and the protective net are installed, whether pedestrians deform through the platform or not and whether the pedestrian support net is obviously shaken or not.

2 mounting assembly type construction channel 8

The channel platforms are placed on a flat ground, the channel platforms with different lengths are combined, the channel protection net is inserted into the corresponding mounting holes of the channel frame, and the channel protection net is connected and fixed by screws. And (3) hanging the installed bent cap passageway platform to a distribution beam 30cm away from the template position by using a crane through a red lifting hook reserved by the platform, placing the platform according to requirements, and fixing the platform with the distribution beam by using a matched U-shaped fastener through a reserved hole on a passageway frame. And (5) connecting and locking the channel platform at the fixed position by using bolts. And a special corner platform is arranged at the diagonal connection position of the two channel platforms, and the two channel platforms are connected and fixed by bolts.

The main materials and equipment required in the present construction process are shown in tables 3 and 4.

TABLE 3 Main materials Table

Table 4 major mechanical equipment configuration table

The assembled prestress bent cap overhanging platform and the construction process thereof have the following benefits:

1 economic benefits

The economic benefit is obvious: taking the construction of the prestressed bent cap with the pier column height of 36m as an example, the installation construction of the fabricated overhanging platform by adopting the shear bar 12 method is compared with the installation construction of the steel tube column type support platform: shortening construction period, saving labor, saving machinery and saving materials.

2 social benefits

The construction progress is quickened: the shear bar 12 method is adopted for assembly type cantilever platform installation construction, the operation is simple, the construction efficiency is remarkably improved, and the construction progress can be accelerated by 66% compared with the steel tube column type overhead support platform installation construction.

The safety risk is reduced: most components of the assembled cantilever platform are assembled on the ground, so that the overhead working time is shortened, and the potential safety hazard caused by long-time overhead working in a complex environment is avoided.

In the construction process of the prestressed cap beam of the pier, the traditional shear bar 12 method is innovated by optimizing the construction process, and the assembled cantilever bracket and the assembled construction channel 8 are applied to the construction of the prestressed cap beam, so that the construction safety risk of the prestressed cap beam is greatly reduced, the investment of personnel materials is saved, and the construction efficiency is improved. The construction period progress and the safety are improved, better economic benefit and social benefit are obtained, and the construction unit and the supervision unit are consistently and well-appreciated in continuous optimization and popularization.

Other embodiments of the utility model will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure of the utility model herein. This application is intended to cover any variations, uses, or adaptations of the utility model following, in general, the principles of the utility model and including such departures from the present disclosure as come within known or customary practice within the art to which the utility model pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the utility model being indicated by the following claims.

It is further understood that the use of relational terms such as "first" and "second", and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. The utility model is not limited to the precise construction which has been described above and shown in the drawings, and various modifications and changes may be made without departing from the scope thereof. The scope of the utility model is limited only by the appended claims.

Claims (7)

1. The utility model provides an assembled prestressing force bent cap platform of encorbelmenting, includes pier shaft (10), shear force stick (12), bent cap body (1) and bent cap support of encorbelmenting, its characterized in that: the novel multifunctional pier comprises a pier body (10), wherein the upper end of the pier body is fixedly connected with a bent cap body (1), a shear bar (12) penetrates through the pier body (10), temporary supports are detachably connected to the outside of the pier body (10), two groups of bent cap cantilever supports are arranged on two sides of the pier body (10) and symmetrically distributed on the two sides of the pier body, each bent cap cantilever support comprises a main cross beam (2), an auxiliary cross beam (3), a main diagonal brace (4), an auxiliary diagonal brace (5) and an outer platform tripod (6), the main cross beam (2) is detachably mounted on the temporary supports, a plurality of outer platform tripods (6) are detachably mounted on the outer side of the main cross beam (2), and the auxiliary cross beams (3) are detachably mounted on two ends of the main cross beam (2);

the novel inclined support is characterized in that the main inclined support (4) is fixedly connected with the main inclined support (4), the main cross beam (2) is detachably connected with the main inclined support (4), the main cross beam (2) and the main inclined support (4) enclose an inverted trapezoid shape, and the main inclined support (4), the main cross beam (2) and the secondary inclined support (5) are detachably connected through bolts.

2. The fabricated prestressed bent cap overhanging platform of claim 1, wherein: the two groups of cantilever brackets of the bent cap are connected through high-strength bolts (15).

3. The fabricated prestressed bent cap overhanging platform of claim 1, wherein: the main beam (2) and the auxiliary beam (3) are internally penetrated by finish rolling deformed steel bars (13), and the main beam (2) and the auxiliary beam (3) are oppositely fixed through the finish rolling deformed steel bars.

4. The fabricated prestressed bent cap overhanging platform of claim 1, wherein: the temporary support comprises channel steel (9) and sand boxes (11), the channel steel (9) is tightly attached to the pier body (10) and is upwards erected on two shear bars (12) on one side of the pier body (10) through a notch, the sand boxes (11) are symmetrically arranged above two sides of the channel steel (9), sand is filled in the sand boxes (11), and the center of the temporary support and the center of a connecting line of the shear bars (12) are on the same vertical line.

5. The fabricated prestressed bent cap overhanging platform of claim 1, wherein: the auxiliary beam lengthening cantilever structure (14) is detachably arranged at one end, far away from the main beam (2), of the auxiliary beam (3).

6. The assembled prestressed bent cap overhanging platform of claim 5, wherein: the auxiliary cross beam (3) and the auxiliary cross beam lengthening cantilever structure (14) are fixedly connected with distribution beams (7), construction channels (8) are detachably connected to the upper ends of the distribution beams (7) through U-shaped fasteners, and the construction channels (8) are assembled construction channels (8).

7. The fabricated prestressed bent cap overhanging platform of claim 1, wherein: the shear bar (12) is a 45# shear bar (12) with the diameter of 16cm, the length of 6m and the weight of 4.8 t.

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