CN-122013806-A - Construction method for section steel conversion beam tower crane foundation borne by underground structure

CN122013806ACN 122013806 ACN122013806 ACN 122013806ACN-122013806-A

Abstract

The invention relates to the technical field of building construction, in particular to a construction method for a section steel conversion Liang Dashi crane foundation carried by an underground structure, aiming at the problems that the field of batch development projects is limited and the original structure is destroyed by the traditional tower crane foundation construction, the method realizes load transmission by relying on a basement frame column through the cooperative design of a fulcrum, a double-layer section steel conversion beam, a connecting beam, a weight underframe and a balancing weight without opening holes on a basement top plate, comprises a welded supporting point arranged at the corresponding position of a basement frame column, a lower layer steel conversion beam, an upper layer steel conversion beam and a connecting beam which are sequentially arranged on the supporting point, a weight underframe is arranged on the upper layer steel conversion beam, and balancing weights are symmetrically arranged, the invention has the advantages of simple operation, high construction efficiency, obviously improved safety and reliability, suitability for batch development projects with existing basements capped and limited sites, and wide engineering application value.

Inventors

HOU XUESONG
SONG DONGHENG
YANG TONGLIN
YANG GUANG
ZHANG HONG
MENG XIANGXU
LI HONGPENG
WANG MINGJUN
LIU PAN
GAO XIAOFEI

Assignees

中建一局集团建设发展有限公司

Dates

Publication Date: 20260512
Application Date: 20260228

Claims (8)

1. The construction method of the section steel conversion beam tower crane foundation borne by the underground structure is characterized by comprising the following steps of: step 1, arranging a supporting point (3), hoisting the prefabricated supporting point (3) to a corresponding position of a basement top plate (2) by using a hoisting machine according to the positioning coordinates of a basement frame column (1), rechecking the plane positioning precision of the supporting point (3) by using a total station, and calibrating the elevation of the supporting point (3) by using a level gauge; Step 2, installing a lower layer type steel conversion beam (4), marking the installation position of the lower layer type steel conversion beam (4) on a fulcrum (3) through an ink line, hoisting the lower layer type steel conversion beam (4) to the fulcrum (3) by using an automobile crane, splicing a plurality of H-shaped steels to form the lower layer type steel conversion beam (4), connecting the splicing parts by adopting groove welding, and fully welding and fixing a splicing joint after rechecking positioning and elevation; step 3, assembling an upper layer type steel conversion beam (5) and a connecting beam (6), welding and forming the upper layer type steel conversion beam (5) and the connecting beam (6) in a processing place in advance according to a design drawing, wherein the upper layer type steel conversion beam (5) adopts H-shaped steel with the specification consistent with that of a lower layer type steel conversion beam (4), the connecting beam (6) adopts I-shaped steel, and a welding node of the connecting beam (6) and the upper layer type steel conversion beam (5) is reinforced by a stiffening plate; step 4, hoisting an upper layer steel conversion beam (5), marking the installation position of the upper layer steel conversion beam (5) on a lower layer steel conversion beam (4), integrally hoisting the assembled upper layer steel conversion beam (5) and connecting beam (6) to the lower layer steel conversion beam (4) by using an automobile crane, rechecking, positioning and elevation by using a total station and a level gauge, and welding the connection node of the upper layer steel conversion beam (5) and the lower layer steel conversion beam (4) by using groove welding; Step 5, installing a weight underframe (7), marking an installation contour line of the weight underframe (7) on the upper layer steel conversion beam (5), welding and forming the weight underframe (7) by adopting a steel plate, hoisting the weight underframe (7) to a designated position by adopting an automobile crane, and fixing the weight underframe (7) and the upper layer steel conversion beam (5) by adopting a welding mode; And 6, arranging and installing the balancing weights (8) with a tower crane, symmetrically hoisting the balancing weights (8) to two sides of the ballast underframe (7), fixing the balancing weights (8) by adopting bolt connection, hoisting pre-buried sections of the tower crane after the installation of the balancing weights (8) is completed, welding and fixing the pre-buried sections with the ballast underframe (7), and sequentially installing standard sections, slewing bearings, crane arms, balance arms and cabs of the tower crane, wherein foundation settlement and horizontal displacement are monitored in real time in the installation process.
2. The construction method of the steel section conversion beam tower crane foundation carried by the underground structure according to claim 1, wherein the supporting point (3) is formed by welding at least four supporting point steel sections (31), the supporting point steel sections (31) are H-shaped steel, supporting point steel plates (32) are wrapped on the upper surface, the lower surface and the side surfaces of the supporting point steel sections (31), and the supporting point steel plates (32) are connected with the supporting point steel sections (31) in a full-welded mode.
3. The construction method of the section steel conversion beam tower crane foundation carried by the underground structure according to claim 2, wherein the number of the fulcrum section steel (31) of the fulcrum (3) is determined according to the bearing capacity of the basement frame column (1), a rubber backing plate with the thickness of 20-30mm is paved between a fulcrum steel plate (32) at the bottom of the fulcrum (3) and the basement top plate (2), and the compressive strength of the rubber backing plate is not lower than 15MPa.
4. The construction method of the steel section conversion beam tower crane foundation carried by the underground structure according to claim 3, wherein a locating pin is arranged on the contact surface of the lower layer steel conversion beam (4) and the supporting point (3), the diameter of the locating pin is 30-40mm, the length of the locating pin is 80-100mm, locating holes are formed in the corresponding positions of a supporting point steel plate (32) at the top of the supporting point (3) and the bottom of the lower layer steel conversion beam (4), and the fit clearance between the locating pin and the locating holes is 0.5-1mm.
5. The construction method of the steel section conversion beam tower crane foundation carried by the underground structure according to claim 1, wherein the distance between the connecting beams (6) is 1.5-2.0m, carbon dioxide gas shielded welding is adopted for welding the connecting beams (6) and the upper layer steel conversion beam (5), the welding current is 200-250A, the voltage is 24-28V, and the welding speed is 3-5mm/s.
6. The construction method of the section steel conversion beam tower crane foundation carried by the underground structure according to claim 1, wherein the anti-skid stripes are arranged on the weight underframe (7), the depth of the anti-skid stripes is 3-5mm, the distance is 50-80mm, the periphery of the weight underframe is provided with flanges with the height of 100-150mm, and the thickness of the flanges is consistent with that of the panel of the weight underframe.
7. The construction method of the steel conversion beam tower crane foundation carried by the underground structure according to claim 6, wherein an anti-corrosion coating is arranged on the surface of the balancing weight (8), and the anti-corrosion coating adopts epoxy zinc-rich primer and polyurethane finish paint.
8. The construction method of the steel-beam-converted tower crane foundation carried by the underground structure according to any one of claims 1-7, wherein submerged arc welding is adopted for welding the tower crane embedded section and the weight underframe (7), and flaw detection is carried out after welding.

Description

Construction method for section steel conversion beam tower crane foundation borne by underground structure Technical Field The invention belongs to the technical field of building construction, and particularly relates to a construction method for a section steel conversion beam tower crane foundation borne by an underground structure. Background Along with the acceleration of the urban process, real estate development projects show large-scale and batch development trends, and a plurality of developers adopt batch development modes of 'building basements firstly and building overground structures later', namely, the construction capping of the whole basement structures is finished firstly, and then the construction of overground buildings is promoted by bidding, in the projects, tower cranes are required to be arranged for overground structure construction, but the basement is capped, so that the traditional tower crane foundation construction method has a plurality of problems. Firstly, the basement roof is provided with holes, so that the original reinforced concrete structure can be damaged, the bearing capacity and the cracking resistance of the basement roof are weakened, the original strength of the structure is difficult to be completely restored in subsequent repair, and the potential safety hazard of the structure is increased; and once again, if the basement roof is improperly waterproof after the hole is formed, the problem of basement leakage is extremely easy to cause long-term hidden danger for subsequent use, and secondly, an independent tower crane foundation is arranged above the basement roof, and loads are dispersed by expanding the foundation bottom area, but the method needs to occupy a large amount of sites, and in batch development projects, the periphery of the basement roof is often occupied by a constructed structure or a construction road, and the sites are limited, so that the method is difficult to implement. In the prior art, partial improvement schemes try to transmit loads by adopting section steel beams, but have the defects that the section steel beams are unreasonable in arrangement, load transmission paths are not clear, local stress concentration is caused, fulcrum design is simple, the cooperative bearing effect with a basement frame column is poor, the basement roof is easy to sink locally, the connection strength between section steel components is insufficient, welding quality is difficult to ensure, balancing weights are arranged asymmetrically, the overall stability of a tower crane foundation is affected, the safety and reliability of the existing improvement schemes are insufficient, the load requirement of a large-scale tower crane is difficult to meet, and the wide application of the large-scale tower crane foundation in engineering is limited. Disclosure of Invention The invention aims to provide a construction method of a section steel conversion beam tower crane foundation carried by an underground structure, which aims to solve the technical problems of avoiding the hole on a top plate of a basement, protecting the integrity of the original structure, eliminating leakage hidden danger, carrying by depending on a frame column of the basement, optimizing a load transmission path and improving the bearing capacity and stability of the foundation in the construction of the tower crane foundation. In order to achieve the above purpose, the invention adopts the following technical scheme: a construction method of a section steel conversion beam tower crane foundation borne by an underground structure comprises the following steps: step 1, fulcrum layout, namely hoisting prefabricated fulcrums to corresponding positions of a basement top plate by using a hoisting machine according to positioning coordinates of basement frame columns, rechecking plane positioning accuracy of the fulcrums by using a total station, and calibrating elevation by using a level gauge, wherein the fulcrums are formed by welding at least four fulcrum section steel, the upper surface, the lower surface and the side surfaces of the fulcrum section steel are wrapped with fulcrum steel plates, and the fulcrum steel plates are connected with the fulcrum section steel in a full-welded mode; Step 2, installing a lower layer type steel conversion beam, marking the installation position of the lower layer type steel conversion beam on a fulcrum through an ink line, hoisting the lower layer type steel conversion beam to the fulcrum by using an automobile crane, splicing the lower layer type steel conversion beam by a plurality of H-shaped steels, connecting the spliced parts by adopting groove welding, and fully welding and fixing a spliced joint after rechecking positioning and elevation; Step 3, assembling an upper layer type steel conversion beam and a connecting beam, welding and forming the upper layer type steel conversion beam and the connecting beam in a processing field in advance accordi