CN114525808B - Deep foundation pit edge gantry crane ground beam construction method - Google Patents

Abstract

A construction method for a gantry crane ground beam at the edge of a deep foundation pit comprises the following steps of grading backfilling treatment is carried out on a clearance space near a retaining wall inclined wall before construction of the gantry crane ground beam, the gantry crane ground beam is poured on a filling body, a main reinforcement protection layer and a temperature seam are arranged, an embedded part is arranged on the gantry crane ground beam, a gantry crane walking track is arranged on the gantry crane ground beam under the cooperation of the embedded part, and the gantry crane ground beam is far away from the deep foundation pit compared with the retaining wall in the direction horizontal to the ground.

Description

Deep foundation pit edge gantry crane ground beam construction method

Technical Field

The invention relates to the field of construction hoisting device erection, in particular to a deep foundation pit edge gantry crane ground beam construction method.

Background

In large road engineering, when a road foundation is constructed, the work of excavating a deep foundation pit is generally required according to requirements, and the deep foundation pit engineering is generally the engineering of excavating and supporting earthwork of foundation pits (grooves) with the excavation depth exceeding 5m or not exceeding 5m but with complicated geological conditions, surrounding environment and underground pipelines or affecting the safety of adjacent buildings (structures) according to regulations. For deep foundation pit constructed by open cut method, in some construction occasions, based on the requirements of some construction, a certain amount of hoisting equipment is required to be arranged on each section of the deep foundation pit to transport the steel support frame and the construction material of the main structure in the foundation pit, and for the heavy and long construction material and the steel support frame, the portal crane with relevant carrying capacity and good use effect becomes a better choice. The general structure of the gantry crane is similar to the shape of a door, and the gantry crane at least comprises a main beam and two supporting legs, wherein the two supporting legs are respectively supported on two ends of the main beam in the length direction, so that the whole gantry crane presents an inverted U-shaped door-shaped or door frame-shaped structure, and in some gantry crane models, an overhanging cantilever beam can be additionally arranged on two ends of the main beam.

The foundation design form adopted by most portal cranes at the erection of the two sides of the deep foundation pit at present is designed integrally with the foundation of the two-side crown Liang Yumen type crane, because the span of the portal crane can be reduced and the occupied space can be saved. However, the arrangement scheme has a great potential safety hazard in the construction process, for example, the derailment of the portal crane can cause serious foundation pit safety accidents, and meanwhile, the construction height of the crown beam can be increased, and the construction cost is increased.

Furthermore, there are differences in one aspect due to the understanding of those skilled in the art; on the other hand, since the applicant has studied a lot of documents and patents while making the present invention, the text is not limited to details and contents of all but it is by no means the present invention does not have these prior art features, but the present invention has all the prior art features, and the applicant remains in the background art to which the right of the related prior art is added.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a construction method of a gantry crane ground beam at the edge of a deep foundation pit, which comprises the following steps of grading backfilling a clearance space near a retaining wall inclined wall before the construction of the gantry crane ground beam, casting the gantry crane ground beam on a filling body, setting a main reinforcement protection layer and a temperature seam, setting an embedded part on the gantry crane ground beam, installing a gantry crane walking track on the gantry crane ground beam under the cooperation of the embedded part, and keeping the gantry crane ground beam far away from the deep foundation pit in the direction horizontal to the ground compared with the retaining wall.

Preferably, the bottom end of the retaining wall is arranged on a crown beam, and the crown beam is formed by communicating the tops of a plurality of underground continuous walls.

Preferably, the diaphragm wall is arranged in a deep groove formed in the soil at the periphery of the edge of the deep foundation pit.

Preferably, the retaining wall bottom width is smaller than Yu Guanliang top width, and the retaining wall is arranged at the top of the crown beam at a position close to one side of the deep foundation pit.

Preferably, the other side of the crown beam far away from one side of the deep foundation pit is contacted with a guide wall, the guide wall is at least provided with a first guide wall surface and a second guide wall surface which are perpendicular to each other, the first guide wall surface is horizontal to the ground and at least provided with one part arranged below the current ground, and the second guide wall surface is perpendicular to the ground and is contacted with the crown beam.

Preferably, a clearance space is formed between the portion of the second guide wall surface beyond the contact to the crown beam and the inclined wall of the retaining wall.

Preferably, the gap space is in a trapezoid structure that a short upper bottom contacts the crown beam and a long lower bottom is far away from the crown beam, and the filling body formed by backfilling in the space is in a uniform structure.

Preferably, the lower bottom of the filling body is coplanar with the first guide wall surface and parallel to the horizontal plane, and a cushion layer is arranged on the lower bottom of the filling body and the first guide wall surface.

Preferably, the gantry crane ground beam is disposed on the bedding layer, and a sum of a ground beam height of the gantry crane ground beam in a vertical direction and a thickness of the bedding layer is equal to a vertical distance from the current ground surface to the first guide wall surface.

Preferably, the gantry crane ground beam is arranged on one side close to the current ground, and the pad body on the other side of the gantry crane ground beam is provided with a drainage ditch contacted with the side edge of the gantry crane ground beam.

The invention has the advantages that the contact position of the gantry crane is arranged at the outer side of the deep foundation pit, and the retaining wall with a slope is introduced to shield the ground beam of the gantry crane, so that even if the problem of horizontal left-right shaking or derailment caused by instability of the supporting legs of the gantry crane occurs, the contact position is blocked by multiple parts such as a drainage ditch and the retaining wall, thereby preventing the serious potential safety hazard caused by tipping of the gantry crane. And the gantry crane ground beam is arranged at the current ground position close to the edge of the deep foundation pit, so that the main bearing of the gantry crane is concentrated on the ground. The gantry crane track sets up in the retaining wall outside, compares the advantage that sets up to have on the roof beam mainly safety, economic nature and material transportation's convenience.

(1) Safety: if the gantry crane track is arranged at the upper part of the foundation pit crown beam, if derailment occurs in the walking process, the gantry crane is likely to fall into the foundation pit, and personal injury is caused to operators in the foundation pit, so that a large safety accident can be caused; if the gantry crane track is arranged on the outer side of the retaining wall, even if derailment occurs, the gantry crane track can not fall into the foundation pit due to the action of the retaining wall, so that larger safety accidents are avoided.

(2) Economy: the cross section size of the enclosure structure and the supporting stress requirement are considered in the arrangement of the foundation pit crown beam, and meanwhile, the design height of the top surface of the crown beam is generally lower than that of the existing ground, if a gantry crane track is arranged at the upper part of the foundation pit crown beam, the cross section size of the crown beam is increased, and the cost is high; the gantry crane track is arranged on the outer side of the retaining wall, and the structural strength of the foundation beam is only required to meet the requirement of the bearing capacity of the gantry crane track foundation through mechanical checking, so that the gantry crane track has the characteristics of small section size, simplicity in construction operation, low cost, convenience in dismantling and the like.

(3) Convenience of material transportation: the gantry crane track is arranged on the outer side of the retaining wall, so that the lifting range of the object at the cantilever end of the gantry crane can be guaranteed to the greatest extent, the loading and unloading of some vehicle-mounted transported materials are extremely convenient, and the material transport vehicle can be directly stopped below the cantilever end of the gantry crane, so that the material transport speed is greatly improved.

Drawings

FIG. 1 is a schematic step diagram of a preferred embodiment provided by the present invention;

FIG. 2 is a schematic overall cross-sectional view of a gantry crane according to a preferred embodiment of the present invention;

In the figure: 001. a ground connecting wall; 002. a crown beam; 003. a filler; 004. a guide wall; 005. a retaining wall; 006. a cushion layer; 007. the current situation ground; 008. gantry crane ground beams; 009. and a drainage ditch.

Detailed Description

The following is a detailed description with reference to fig. 1 and 2.

In large road construction, for the purpose of building a solid foundation of a road, it is necessary to excavate a deep foundation pit which is a foundation pit engineering of which the excavation depth is more than 5m or which is an engineering of earth excavation, supporting of a foundation pit (trench) which affects safety of an adjacent building (structure) due to geological conditions, surrounding environment and underground pipelines although the excavation depth is not more than 5m, the deep foundation pit structure is of a similar trench type or U-shaped structure, a middle portion thereof is recessed below the ground and is usually flattened into a plane, and both sides extend downward along the ground or near the ground position and border the middle portion. The two sides of the deep foundation pit are provided with the crown beams 002, the crown beams 002 are beam structures arranged on the top surfaces of the foundation pit slope protection piles, and the effect of the crown beams 002 is to interconnect the slope protection piles which are arranged at intervals along one single side of the length direction of the deep foundation pit together to form a complete whole so as to enhance the effect of the slope protection piles on preventing the edge of the deep foundation pit from collapsing. The structure of the slope protection pile is similar to a cylindrical structure, also called a row pile, and the slope protection pile is a pile which is arranged along the edge of a foundation pit and used for preventing a side slope from collapsing, and can effectively prevent foundation displacement, sinking and the like of adjacent original projects, and one of the purposes of arranging the crown beams 002 is to connect the slope protection piles which are arranged at intervals together so as to strengthen the integral stress resistance of the slope protection piles.

For the purpose of transporting steel support frames and some main structure construction materials in deep foundation pits, in some projects, a portal crane needs to be arranged above the deep foundation pit, the general structure of the portal crane is similar to the shape of a door, the portal crane is at least composed of one main beam and two support legs, the two support legs are respectively supported on two ends of the main beam in the length direction so that the crane integrally presents an inverted U-shaped portal or door frame structure, and in some portal crane models, overhanging cantilevers can be additionally arranged on two ends of the main beam. By the above, the gantry crane is provided with at least two supporting leg structures, and is a groove-shaped structure matched with the deep foundation pit and the main girder bearing of the gantry crane, the two supporting legs are generally placed on two sides of the deep foundation pit close to the ground plane, and in the existing engineering, the two supporting legs of the gantry crane are often respectively arranged on the crown girders 002 arranged on two sides of the deep foundation pit. Because the row piles forming the crown beams 002 are just arranged along the two sides of the length trend of the deep foundation pit respectively, the trend of the crown beams 002 also just accords with the length trend of the deep foundation pit, and the supporting legs erected on the two crown beams 002 enable the main girder of the gantry crane to be transversely arranged above the deep foundation pit so as to hoist articles in the deep foundation pit.

However, the gantry crane provided on the crown beam 002 has a great potential safety hazard in use, because the foundation of the crown beam 002 is some slope protection piles or row piles, the crown beam 002 is subsequently constructed on the foundation of the piles, if the floating slurry at the upper end of the row piles is not or not effectively shoveled out during the construction of the crown beam 002, the structure of the crown beam 002 is likely to be unstable, and particularly after the rails used for supporting legs of the gantry crane are additionally provided on the crown beam 002, under the heavy pressure of the gantry crane, the crown beam 002 has a great potential safety hazard, such as shaking caused by unstable gravity center and uneven rails caused by subsidence of part of the row piles, which may cause the derailment problem of the gantry crane. If the safety of the crown beam 002 is required to be improved, the construction of crown beam reinforcement, elevation, foundation reinforcement, etc. is required, but this is certainly an increase in construction cost.

The invention provides a deep foundation pit edge gantry crane ground beam construction method which is used for supporting engineering construction of gantry cranes arranged on two sides of a deep foundation pit. According to the scheme, the gantry crane considers the safety of the foundation pit, and the crane track is arranged on the outer side of the deep foundation pit retaining wall. The foundation is simple in construction, the construction cost is low, and potential safety hazards caused by derailment to the foundation pit can be reduced to the greatest extent.

Specifically, the construction scheme will be described in more detail, as shown in fig. 1, this is a schematic structural diagram of a track setting position used by a gantry crane, that is, a gantry crane, where no part of the gantry crane is shown, and the track setting position also shows only a half part, and it should be noted that the structure shown in the figure is at least symmetrical about a center line of a deep foundation pit, that is, the track setting position has at least two symmetrical positions, and can be respectively suitable for mounting and carrying two support legs of the gantry crane. The road side structure shown in fig. 1, i.e. the structure on the side of the non-excavated road around the deep foundation pit, is seen to have a section of the current ground 007, which is located on the left side in the illustration and the deep foundation pit section is located on the right side in the illustration, which is located on the other side from the current ground 007, as can be understood in connection with fig. 2. The above-described left and right positional descriptions are merely for the positional relationship shown in the drawings, and actually merely indicate the relative positional relationship between the current ground 007 and the deep foundation pit, irrespective of the actual left and right directions.

The continuous wall structure as bearing and water retaining is arranged on the two circumferential sides of the deep foundation pit in the length direction, at least one part of the continuous wall structure is deeply buried in the soil on the circumferential side, the continuous wall can be called an underground continuous wall or a ground continuous wall 001, a plurality of long and narrow deep grooves which are deep into the soil are dug on the circumference of the excavation engineering, namely the circumferential side of the deep foundation pit in the embodiment under the condition of mud protection, and a low concrete wall structure formed by combining a plurality of strip-shaped concretes formed by placing reinforcement cages in the deep grooves and pouring concrete into the reinforcement cages is used for foundation bearing of the gantry crane because the low concrete wall structure is formed by the reinforced concrete, and has better bearing capacity and water resistance, seepage resistance and water interception functions.

The continuous wall is formed by pouring a long and narrow steel reinforcement cage which is formed by being matched with long and narrow deep grooves excavated on the periphery of a deep foundation pit from a separate individual, and is similar to a columnar, rod-shaped or strip-shaped structure, so that the continuous wall has the same structure and similar functions as the slope protection pile, and can be regarded as the same component. Then, similarly, the portion formed by connecting the top ends of the plurality of ground continuous walls 001 arranged according to the length direction of the deep foundation pit may be called a crown beam 002. In contrast to the conventional art in which the track is provided directly on the crown beam 002, this embodiment does not do so, but a retaining wall 005 is provided on top of the crown beam 002. In this embodiment, in the index for deep foundation pit excavation, the depth of the deep foundation pit is at least Yu Guanliang a sum of the height of the deep foundation pit and the height of the retaining wall 005, for convenience of description, the pit bottom plane of the upgrade pit may be set as the initial plane, the distance generated by moving an imaginary point from the initial plane vertically upward away from the initial plane is calculated as a height value accumulated from 0, and the height of the crown beam 002 may be referred to as the first height, and the first height may be expressed as the distance of the top of the crown beam 002 from the initial plane, which is equivalent to a length portion where the continuous wall constituting the crown beam 002 goes deep into the deeper position of the bottom of the deep foundation pit, without consideration. The height of the retaining wall 005 may be referred to as a second height, which is a vertical height from the bottom to the top of the structure of the retaining wall 005 itself, and since the retaining wall 005 is directly disposed on the crown beam 002 in a bottom-contact manner, the sum of the first height and the second height may represent the distance of the top of the retaining wall 005 from the initial plane, that is, the total height. The depth of the deep foundation pit may be referred to as a third height from the point of view of the initial plane, and the three heights are related in such a way that the sum of the first height and the second height is greater than or equal to the third height. In order to ensure the self strength and the functionality of the retaining wall 005 and the crown beam 002, the first height and the second height cannot be too small or too large, and the heights of the retaining wall 005 and/or the crown beam 002 can be specifically designed according to the requirements of the engineering site.

The retaining wall 005 forms a trapezoid surface as viewed in cross section, i.e., the retaining wall 005 itself is formed in a shape similar to a slope or a sloping structure, and the width of the bottom of the retaining wall 005 connected to the crown beam 002 is not exactly matched to the width of the top of the crown beam 002 but is smaller Yu Guanliang than the width of the top of the crown beam 002, the width of the bottom of the retaining wall 005 may be referred to as a first width, the width of the top of the crown beam 002 as a second width, and the first width is smaller than the second width.

The retaining wall 005 is close to one side of the deep foundation pit, and the other side far from one side of the retaining wall 005 is provided with a guide wall 004. Before the deep groove is formed by constructing the continuous wall, in order to ensure the direction of forming the groove and the effect of shielding soil on the side wall, a guide wall 004 is firstly constructed on the side wall of the deep foundation pit. Guide wall 004 is generally L-shaped having two mutually perpendicular planes, one plane being generally parallel to the ground during construction and the other plane being generally parallel to the side walls of the deep foundation pit, i.e. perpendicular to the ground. In this embodiment, the above-described surface parallel to the ground is provided below the current ground 007, which may be referred to as a first guide wall 004 surface, and accordingly, the other surface of the guide wall 004 may be referred to as a second guide wall 004 surface. The connecting wall and the crown beam 002 formed on the top thereof are horizontally positioned closer to the center line of the deep foundation pit than the second guide wall 004 (not shown).

As described above, the retaining wall 005 has a width smaller than the width of the top part Yu Guanliang, and thus a space, which may be called a gap space, is formed above the top part of the crown beam 002, and the gap space is filled in a graded backfill rammed manner so as to be formed as a solid body, which may be called a filling body 003. As described above, the gap space, including the filling body 003 formed by filling the gap space, is in an inverted trapezoid structure, and if a longer bottom edge is called a lower bottom edge, and a shorter bottom edge is called an upper bottom edge, the upper bottom edge is close to the top position of the crown beam 002, and the lower bottom edge is far from the top of the crown beam 002 and is coplanar with the first guide wall 004.

As described above, the first guide wall 004 is constructed below the current ground 007, and thus the vertical distance of the current ground 007 surface to the first guide wall 004 may be referred to as the first vertical distance. The current ground 007 has a certain horizontal distance from the junction between the first guide wall 004 and the second guide wall 004, that is, the edge of the first guide wall 004 near the side of the deep foundation pit, in the horizontal direction, and this distance may be referred to as a first horizontal distance. That is, the current ground 007 does not cover the entire area of the first guide wall 004, but only a covered portion.

The pad layer 006 is covered on the bottom of the filler 003 and the upper part of the first guide wall 004 surface part partially exposed outside the coverage area of the current ground 007, the size of the pad layer 006 can be selected according to the actual engineering situation, in this embodiment, a C15 pad layer 006 with a thickness of 10cm can be selected, and the thickness of the pad layer 006 can be referred to as the thickness of the pad layer 006. At least a portion of the mat 006 is disposed below the current ground 007. In particular, the length of the mat 006 in horizontal cross section (as viewed in the figures) may be referred to as the width of the mat 006, one end of the width of the mat 006 starting at the current ground 007 and extending to the sloped wall of the retaining wall 005 adjacent the deep foundation pit. The width of the portion of mat 006 that is pressed down by current ground 007 may be expressed numerically as the width of mat 006 minus the first horizontal distance and the length of the bottom of filler 003.

The overhead area of the cushion 006 is provided with gantry crane ground beams 008 and gutters 009. The gantry crane floor beam 008 is substantially rectangular in overall view of the track, has two edge length values as viewed in cross section in the drawing, the edge length in the horizontal direction may be referred to as a floor beam width value, and the edge length in the vertical direction may be referred to as a floor beam height value. Based on different engineering requirements, such as different gantry crane dead weights and expected bearing weights. In this example, a dimension scheme was selected in which the land beam width values are 300mm by 400 mm.

The drainage ditch 009 is generally a groove structure, which is used to drain rainwater or other water out of a construction site, and the width of the drainage ditch 009 along the horizontal direction may be referred to as the width of the drainage ditch 009, so that the sum of the width of the drainage ditch 009 and the width of the ground girder is approximately equal to the sum of the first horizontal distance and the length of the bottom of the filler 003, and the above description is "approximately" considering the case of the inclined wall structure of the retaining wall 005, and the widths of the layers on the horizontal plane may be slightly different depending on the inclined wall structure of the retaining wall 005. Here, the positions of the above-described structures at each vertical height may be described in a direction perpendicular to the ground. A part of the underground continuous wall 001 at the lowest position is deeply buried in a deep groove in the soil; the tops of the plurality of the ground continuous walls 001 are communicated to form a crown beam 002; a retaining wall 005 with the bottom width smaller than Yu Guanliang and the top width of the top beam 002 is constructed on one side of the top of the crown beam 002 close to the deep foundation pit, a guide wall 004 is constructed on one side of the crown beam 002 close to the current ground 007, the construction time of the guide wall 004 is earlier than that of the underground continuous wall 001, and a second guide wall 004 perpendicular to the ground of the guide wall 004 extends upwards beyond the crown beam 002; the second guide wall 004 surface and the side wall of the retaining wall 005 form a clearance space which is approximately trapezoid above the crown beam 002, and the clearance space is filled into a filling body 003 with approximately consistent shape by using a grading backfilling tamping mode; the lower bottom surface of the filler 003 with longer length is coplanar with the first guide wall 004 surface and is horizontal to the ground; a portion of the first guide wall 004 face is disposed under the current ground 007 in an embedded manner; a cushion layer 006 is constructed above the first guide wall 004 surface and the lower bottom surface of the filler 003 beyond the range of the current ground 007; a gantry crane ground beam 008 and a drain 009 are constructed above the cushion 006. The cushion layer 006, the drain 009 and the side of the filler 003 near the deep foundation pit all contact the inclined wall of the retaining wall 005. The first vertical distance is equal to the sum of the floor height and the width of the cushion 006, in this embodiment 100mm+400mm=500 mm.

In one embodiment, the method steps are as follows.

S1, grading backfilling treatment is carried out on the clearance space near the inclined wall of the retaining wall 005 before construction of the gantry crane ground beam 008 to form a filler 003, grading backfilling is carried out by adopting grading sand stone (secondary ash) for grading backfilling, and then tamping is carried out.

The above-mentioned tamping may be performed manually or by mechanical tamping.

S2, pouring a gantry crane ground beam 008 on the filling body 003, and setting a main reinforcement protection layer and a temperature seam.

In the embodiment, the gantry crane ground beam 008 is poured by C25 concrete, and the thickness of the main reinforcement protective layer is 40mm. Every 40m is provided with a temperature seam, and the construction length of each section of ground beam can be set on site according to actual conditions.

In the embodiment, the main reinforcement of the ground beam is divided into 3 layers, the upper layer adopts 3C14, the middle layer adopts 2C12, the lower layer adopts 4C16+2C12, and the stirrup adopts A6.5 with a spacing of 200mm.

S3, arranging an embedded part on the gantry crane ground beam 008, wherein the embedded part is made of a 300 multiplied by 100 multiplied by 20mm steel plate, and 2 steel bars 300mm long A10 are anchored in the steel plate. Plug welding is adopted between the steel plate and the steel bar, and the space between embedded parts is 900mm.

The embedded part is used for fixing the I-shaped track, so that the embedded part cannot generate deflection, horizontal vibration, displacement and the like on the ground beam.

And S4, installing a gantry crane walking track on the gantry crane ground beam 008 under the cooperation of the embedded part.

After the construction of the ground beam is completed, the supporting legs of the gantry crane can be arranged on the travelling rail of the gantry crane.

In this embodiment, the filling body 003 is formed by filling graded sand, instead of the conventional scheme of concrete pouring, which is due to the gantry crane ground beam 008 arranged above the filling body 003, and when the supporting leg of the gantry crane contacts the gantry crane ground beam 008, at least half of the weight of the gantry crane is transferred to the filling body 003 on one side. And because the lifting structure on the gantry crane can move along the direction transversely arranged on the foundation pit, the pressure applied to the ground direction by the supporting legs erected on the two sides of the foundation pit is not consistent in some time, and the gravity center deviation causes that the filling bodies 003 on the two sides of the foundation pit can bear different pressures at different times under different working conditions. Therefore, the scheme of graded sand and stone layered filling adopted by the scheme can effectively alleviate the problem, wherein sand in the filling component is formed into a substance for filling gaps among fine stones, so that the filling body 003 can be filled with sand to form a firmer filling body 003 in a mode that microscopic fine gaps are filled with sand after backfilling and tamping. Moreover, stones in the sand material, i.e. stones, constitute an initial gravitational compression of the gantry crane or cause the influence of the varying pressure of the gantry crane on the filler 003 to become dispersed during operation. Specifically, the conventional means constructs the filler 003 by using concrete, and the filler 003 is subjected to the pressure of the gantry crane, particularly to the changing pressure generated during gantry crane lifting or the internal stress change caused by hydration heat in the interior of the filler when the thermal management is poor in the concrete pouring process, so that cracks are likely to be generated in the concrete or the cracks are increased, and finally the filler 003 is easily cracked, so that the ground beam 008 of the gantry crane arranged on the filler is loosened or collapsed, and serious accidents such as derailment of the gantry crane are caused. The sand stone grading filling adopted by the scheme is provided with a plurality of tiny stones which are mixed and randomly positioned, the physical strength of the sand stone grading mixture can be enhanced, and the stones or the adjacent stones have certain buffering performance, and the stones have certain elasticity, so that the pressure or the changed pressure generated by the gantry crane can be buffered, and meanwhile, the internal deformation of the produced filling body 003 can be repaired or recovered through the filling effect and the elastic effect of the stones.

This scheme sets up the gantry crane track in retaining wall 005 outside, compares the advantage that sets up to have on the roof beam 002 and mainly is security, economic nature and material transportation's convenience, and specific advantage is as follows.

(1) Safety: if the gantry crane track is arranged on the upper part of the foundation pit crown beam 002, if derailment occurs in the walking process, the gantry crane is likely to fall into the foundation pit, and personal injury is caused to operators in the foundation pit, so that a large safety accident can be caused; if the gantry crane track is arranged on the outer side of the retaining wall 005, even if derailment occurs, the gantry crane track can not fall into the foundation pit due to the action of the retaining wall 005, so that larger safety accidents are avoided.

(2) Economy: the cross section size of the enclosure structure and the supporting stress requirement are considered in the arrangement of the foundation pit crown beam 002, meanwhile, the design height of the top surface of the crown beam 002 is generally lower than that of the current ground 007, if a gantry crane track is arranged on the upper part of the foundation pit crown beam 002, the cross section size of the crown beam 002 can be increased, and the cost is high; the gantry crane track is arranged on the outer side of the retaining wall 005, and the structural strength of the foundation beam is only required to meet the requirement of the bearing capacity of the gantry crane track foundation through mechanical checking, so that the gantry crane track has the characteristics of small section size, simplicity in construction operation, low cost, convenience in dismantling and the like.

(3) Convenience of material transportation: the gantry crane track is arranged on the outer side of the retaining wall 005, so that the lifting range of the object at the cantilever end of the gantry crane can be guaranteed to the greatest extent, the loading and unloading of some vehicle-mounted transported materials are extremely convenient, and the material transport vehicle can be directly stopped below the cantilever end of the gantry crane, so that the material transport speed is greatly improved.

This scheme removes the earth beam mounted position that is used for setting off the track of gantry crane from conventional crown beam 002 top position to foundation ditch outside current situation ground 007 position for the space at crown beam 002 top is released, and this scheme is provided with the backfill structure and the retaining wall 005 structure that can strengthen the dominant property of crown beam 002 itself and the dominant property of gantry crane earth beam 008 simultaneously at crown beam 002 top by this, except can prevent to lead to the gantry crane derailment with the conventional scheme of track setting up on crown beam 002, and the gantry crane that then causes breaks into the foundation ditch and causes the incident problem, but also utilizes crown beam 002 released space to in turn to provide the effect complemental to the setting strength, the environmental safety protection of earth beam and crown beam 002 itself.

First, the top surface of the crown beam 002 is designed to be lower than the current ground 007, and the current ground 007 is the ground of the foundation pit with the surrounding side higher than the bottom of the foundation pit in elevation, and is generally the ground with certain compliance strength which is already constructed.

In the prior art, a gantry crane track is arranged above a crown beam 002 inside a deep foundation pit, after the gantry crane is installed and put into use, partial settlement of the bottom of the foundation pit can be caused in the load operation process, and larger construction errors can be caused under the condition that no countermeasure construction measures or redundant design is carried out, so that a series of other foundation pit structure problems are caused. Meanwhile, the operation of the gantry crane also causes a certain deformation influence on the crown beam 002 and the foundation pit slope support of which the foundation of the crown beam 002 is partially formed, after a certain deformation value exceeds a designed bearable limit, the crown beam 002 or the corresponding support can be damaged and irrecoverably deformed due to strong strain force, so that more engineering problems are caused, and the engineering has to be suspended or reversed to maintain the supports and the crown beam 002, so that the whole engineering progress is dragged slowly, and the construction efficiency is seriously reduced. On the other hand, the arrangement of the gantry crane ground beam 008 on the inner side of the foundation pit is actually to hook the use foundation of the gantry crane and the structural attribute of the foundation pit, so that the property of the gantry crane is influenced by the condition of the foundation pit in the condition, if the foundation pit has the problems of larger transverse deformation, longitudinal deformation, sedimentation and other structural changes in the subsequent excavation, repair excavation, adjustment, reconstruction and other projects, the gantry crane can bear corresponding deformation strain force in a peer-to-peer manner, and the gantry crane can have metal stress relaxation or metal fatigue phenomenon of a steel structure influenced by stress for a long time under the condition of light strain force degree, so that the potential safety hazard of the gantry crane steel structure fracture is formed; in the case of a relatively small degree, the axial bending of the gantry crane causes unbalanced lifting points, the non-centering of the lifting points reduces the lifting effect or the supporting legs of the gantry crane cannot smoothly move on the track due to the torsional stress in the direction which is not parallel to the track, so that the gantry crane cannot normally operate, and constructors have to correct the problem of the gantry crane, but in the case, the structural correction of the large structure built in the foundation pit is actually inconvenient, otherwise a great amount of engineering expenditure and engineering progress are consumed; under the condition of heavier degree, the gantry crane is subjected to the direct structural collapse of the stress which is difficult to bear, or the gantry crane supporting legs are directly derailed from the tracks on the two sides, then the tracks are crashed into the foundation pit in a short time, and serious safety accidents are caused, and the situation can happen at any moment when the structure of the foundation pit is expanded or modified or other structures in the foundation pit are constructed by engineering, so that engineering personnel are required to pay attention to the state of the gantry crane at any moment when the construction related to the foundation pit is carried out, the situation that the gantry crane is suddenly crashed due to the related attribute change of the foundation pit is prevented, a great deal of engineering effort is consumed, and the engineering progress is seriously dragged.

However, the present embodiment solves the above-described problem well by moving the installation position of the gantry crane rail to the position of the current ground 007 outside the foundation pit. Firstly, the state attribute of the gantry crane is directly unhooked from various conditions in the foundation pit, compared with a foundation pit with a complicated and changeable structural state along with construction, the existing ground 007 has quite state stability because a relatively stable structure is formed and basically does not belong to the construction category, so that the gantry crane is not influenced by almost any construction operation in the foundation pit and natural change of the foundation pit, has quite safety, use stability and easy maintenance, and is beneficial to improving construction progress and more reasonable distribution of construction resources. Meanwhile, the influence of the gantry crane on the crown beam 002 and the support is directly cleared, an additional redundant structure is not required to be arranged or a maintenance related structure is not required to be paid attention to at any time, so that engineering resources can be used in construction projects with higher priority. In addition, the correction of the gantry crane track is relatively simpler because the gantry crane track is positioned on the side with a stable structure. Simultaneously, still directly letting out the crown beam 002 headspace that originally is used for setting up the track with portal crane track migration to the foundation ditch outside, this scheme has then set up on this spare space and has joined in marriage the packing body 003 and retaining wall 005 of backfilling.

The top of crown beam 002 occupies a part, based on backfilling, the sand and stone filling body 003 with higher density is produced, at first shelter from and unify the foreign matter and the external force influence at crown beam 002 top for crown beam 002 top can not receive the external force influence to crown beam 002 top that rainfall, unexpected falling object, engineering misoperation caused for example, make the structural integrity at crown beam 002 top be guaranteed, still made further assurance to the structural integrity of crown beam 002 outside releasing crown beam 002 bears the hidden danger of gantry crane floor beam 008. Second, the backfill layer enhances the uniformity of the base support force of the crown beam 002 in the height direction, enabling it to carry the high-rise (i.e., current ground 007 level) build in a stronger, more stable manner.

Backfilling provides additional shielding stability in the horizontal direction for the guide wall 004. In conventional approaches, especially when the crown beam 002 is positioned below the current ground 007, the portion of the guide wall 004 that is immediately adjacent to the foundation pit wall is exposed to the outside, which is first susceptible to damage from the remaining components operating within the foundation pit, such as during construction operations within the foundation pit.

Meanwhile, the side of the guide wall 004 on the horizontal plane is easy to receive lateral movement force in the horizontal direction, which is generated by the pressure from the approximately vertical direction to the stratum soil, and the lateral movement force is particularly huge when the guide wall 004 is provided with the gantry crane ground beam 008 and the track and then walks through the gantry crane, and if the horizontal lateral movement force is not blocked, the lateral movement of the guide wall 004 is easily caused, even the guide wall 004 in the direction is broken, so that the stable fixing effect on the side slope of the foundation pit is lost, and the side slope collapse is caused. And the upper part of the crown beam 002 is clear, so that a filling body 003 can be arranged to block one side of the guide wall 004 at the side of the foundation pit to a certain extent, thereby additionally realizing the structural protection of the guide wall 004.

The collecting and backfilling is the mixture of soil and stones, the texture is relatively soft, a certain elastic absorption effect is achieved, the collecting and backfilling device is arranged on one side close to the ground beam, and can absorb a part of vibration of the ground beam 008 of the gantry crane, and in the running process of the gantry crane, the backfilling area is further tamped, so that the structure is more stable and firm;

The gravity retaining wall 005 can be used at the roof beam 002 top, need not to carry out a large amount of ramming work and worry the slip phenomenon of backfilling soil body, especially has portal crane gravity oppression to transfer to the ascending application force of horizontal plane at the top, if not adopting gravity retaining wall 005, causes the fill body to slide easily, the land beam is not hard up, leads to derailment scheduling problem. The crown beam 002 has excellent stability as a foundation, and can be just used as a construction foundation of the gravity type retaining wall 005, and the retaining wall 005 simultaneously provides additional compaction effect for the stability of the crown beam 002 and the support of the bottom of the crown beam 002 in the horizontal direction by the gravity of the retaining wall 005.

At the same time, a cushion layer 006 and an additional drainage ditch 009 can also be arranged above the filling body 003, and according to the conventional scheme, as the top of the crown beam 002 is occupied by the gantry crane ground beam 008, the position has no resistance to foreign matters from the top space of the position, especially for water accumulation falling from the top, such as rainwater or water accumulation flowing out of the edge of a foundation pit, the top of the crown beam 002 is possibly washed by water, and meanwhile, a plurality of supports below the crown beam 002 are occupied by space, no good scheme is provided for drainage measures, and finally the water accumulation at the support positions below the crown beam 002 is serious.

With the track setting in the foundation ditch periphery outside the roof beam 002 for roof beam 002 headspace is liberated, has given simultaneously and has been backfilled and the lifting to the space of position setting escape canal 009 on ground at roof beam 002, makes the escape canal 009 of script can participate in the drainage process of foundation ditch week side under the condition that does not receive the roof beam 002 influence, further promotes the prevention of seepage water stability of foundation ditch side slope, compares in the conventional scheme with the track setting in roof beam 002 top, and this scheme has realized preventing to the infiltration.

It should be noted that the above-described embodiments are exemplary, and that a person skilled in the art, in light of the present disclosure, may devise various solutions that fall within the scope of the present disclosure and fall within the scope of the present disclosure. It should be understood by those skilled in the art that the present description and drawings are illustrative and not limiting to the claims. The scope of the invention is defined by the claims and their equivalents. The description of the invention encompasses multiple inventive concepts, such as "preferably," "according to a preferred embodiment," or "optionally," all means that the corresponding paragraph discloses a separate concept, and that the applicant reserves the right to filed a divisional application according to each inventive concept.

Claims (7)

1. A construction method of a deep foundation pit edge gantry crane ground beam,

It is characterized in that the method comprises the steps of,

Comprises the steps of,

Grading backfilling treatment is carried out on a clearance space near an inclined wall of a retaining wall (005) before construction of a gantry crane ground beam (008) to form a filling body (003), the gantry crane ground beam (008) is poured on the filling body (003) so that at least half of the weight of the gantry crane is transferred to the filling body (003) on one side, the upper bottom of the filling body (003) is coplanar with the first guide wall surface and parallel to the horizontal plane, a cushion layer (006) is arranged on the upper bottom of the filling body and the first guide wall surface, the gantry crane ground beam (008) is arranged on the cushion layer (006),

A main reinforcement protective layer and a temperature seam are arranged, an embedded part is arranged on a gantry crane ground beam (008), a gantry crane walking track is arranged on the gantry crane ground beam (008) under the cooperation of the embedded part,

In the direction horizontal to the ground, the gantry crane ground beam (008) is further away from the deep foundation pit than the retaining wall (005) and is positioned on the current ground (007) at the edge of the deep foundation pit,

The retaining wall (005) is arranged at the top of the crown beam (002) near one side of the deep foundation pit,

The utility model discloses a deep basal pit, including crown roof beam (002), guide wall (004) are kept away from to opposite side of one side of the deep basal pit, guide wall (004) have at least mutually perpendicular's first guide wall face and second guide wall face, first guide wall face is horizontal to ground and has at least one part to set up in current situation ground (007) below, second guide wall face perpendicular to ground and with crown roof beam (002) contact, the second guide wall face surpass the contact to between the inclined wall of crown roof beam (002) part with retaining wall (005) constitutes the clearance space.

2. The method according to claim 1, wherein the bottom end of the retaining wall (005) is arranged on a crown beam (002), and the crown beam (002) is constructed by communicating the tops of a plurality of diaphragm walls (001).

3. The method according to claim 2, characterized in that the diaphragm wall (001) is arranged in a deep groove formed in the soil at the periphery of the edge of the deep foundation pit.

4. The method according to claim 1, wherein the retaining wall (005) bottom width is smaller than the crown beam (002) top width.

5. The method according to claim 1, characterized in that the interstitial spaces are in the form of a short lower base contact to the crown beam (002), a long upper base being remote from the trapezoid structure of the crown beam (002).

6. The method of claim 1, wherein a sum of a floor height of the gantry crane floor (008) in a vertical direction and a thickness of the bedding (006) is equal to a vertical distance of the current ground (007) surface to the first guide wall surface.

7. The method of claim 6, wherein one side of the gantry crane ground beam (008) is close to the current ground (007) and the other side of the gantry crane ground beam (008) is provided with a drain (009) in contact with the side of the gantry crane ground beam (008), the drain (009) being provided on the bedding layer (006).