CN214143657U - Assembled grid underground continuous wall of dry-type connection - Google Patents

Abstract

The utility model discloses a dry-connected assembled grid underground continuous wall, which is formed by splicing prefabricated wall units, wherein the cross section of each prefabricated wall unit is a hollow square-shaped structure, both sides of each prefabricated wall unit are provided with a through long groove and pre-buried positioning section steel, and both ends of each prefabricated wall unit are provided with anchoring connecting pieces; the anchoring connecting piece is in an open cavity box shape, two sides of the anchoring connecting piece are anchored with the wall longitudinal ribs, and the connecting end is communicated with and corresponds to the wall reserved hole channel; the connecting ends of the vertical adjacent prefabricated wall units are anchored through the high-strength connecting steel bars by aligning, splicing and anchoring connecting pieces; transversely adjacent prefabricated wall units are engaged through the pre-buried positioning section steel, so that after the lateral grooves are spliced to form grouting holes, the micro-expansion early-strength high-ductility cement-based composite material is filled in the grouting holes. The utility model discloses the installation is swift, and waterproof performance is good, and bending rigidity is big, can do the basement outer wall concurrently, is favorable to the industrial production and the construction of underground continuous wall.

Description

Assembled grid underground continuous wall of dry-type connection

Technical Field

The utility model belongs to assembled underground structure technique especially relates to an assembled grid underground continuous wall that dry-type is connected.

Background

With the acceleration of urbanization process, urban construction land is increasingly tense, and the development and utilization of underground space gradually become one of the key fields and main directions of civil engineering construction development. The underground continuous wall is used as a main technology for supporting the foundation pit, has small construction vibration and low noise, and is suitable for urban construction; the wall has the advantages of high rigidity, good seepage-proofing performance and relatively small influence on peripheral buildings or pipelines; the method is suitable for the situation of complex geological conditions; the method has the advantages of high efficiency, quick construction period, reliable quality and good economic benefit, and is more and more widely applied to urban underground engineering.

Accordingly, there are many problems and disadvantages with the conventional underground diaphragm wall. Firstly, waiting for the concrete solidification to cause the prolongation of the construction period, using the cast-in-place underground continuous wall as an underground large concrete supporting structure, and further constructing after the concrete of the underground continuous wall is solidified and reaches a certain strength in earthwork excavation, which is not in accordance with the requirement of shortening the construction period as much as possible in urban underground space construction. Quality is difficult to guarantee when pouring, and when even pouring under water of wall, the mud is pressed from both sides easily to the concrete, is stained with mud on the reinforcing bar when putting the steel reinforcement cage, reduces concrete reinforcement bond stress, and wall body quality is difficult to guarantee, and easily causes the irregular infiltration of wall. And thirdly, the flatness of the wall surface in the weak stratum is not easy to control when the soil layer is weak or a sand layer, if slurry is not properly treated, the problem of collapse of the wall surface is solved, the wall surface has a convex phenomenon, and the flatness of the wall surface is difficult to control. Fourthly, in order to avoid the collapse of the wall of the tank, the quality of the slurry retaining wall needs to be accurately controlled, and meanwhile, the slurry discharge amount in the construction process is large, the energy and resource consumption is large, and the environmental pollution is serious.

Based on the prior art and the existing problems, the development of the prefabricated underground continuous wall becomes a direction capable of solving the existing problems, but the use of the existing prefabricated underground continuous wall is not wide, and the following reasons exist. Firstly, the water stopping effect of the joints between the assembled walls is poor, and the connecting effect of the joints of the walls is difficult to ensure. And secondly, if the solid-web assembled underground diaphragm wall is adopted, the safety is good, but the construction period and the construction cost are relatively highest, the self weight of the wall body is overlarge, the hoisting and the transportation are difficult, and the limitation on the wide popularization and the engineering application is large. Thirdly, the prior construction of most assembled structures is mainly based on wet connection, so that the construction period is difficult to be obviously shortened.

SUMMERY OF THE UTILITY MODEL

Utility model purpose: to the problem that above-mentioned prior art exists, the utility model provides an assembled grid underground continuous wall that dry-type is connected.

The technical scheme is as follows: assembled grid underground continuous wall of dry-type connection, transversely form with vertical concatenation by the prefabricated continuous wall body unit of a plurality of. The section of each prefabricated underground continuous wall body unit is in a hollow square shape, the left side and the right side of each prefabricated underground continuous wall body unit are provided with a through long groove and pre-embedded positioning section steel, and the upper end and the lower end of each prefabricated underground continuous wall body unit are provided with a plurality of anchoring connecting pieces anchored with the longitudinal ribs of the wall body unit. Two adjacent vertical prefabricated wallboard units are spliced through the alignment of the anchoring connecting piece and the high-strength connecting steel bar and screwed down by bolts. Two adjacent transverse prefabricated wall units are occluded through positioning embedded profile steel, and after the lateral grooves of the left wall unit and the right wall unit are spliced to form grouting holes, the high-performance cement-based composite material is filled in the grouting holes.

Wherein the concrete strength of the underground continuous wall is 30-60 MPa. The wall body has the single-wall thickness of 200-. Both sides are provided with a through long groove and a positioning section steel.

Furthermore, the anchoring connecting piece is made of a Q335 steel plate, the anchoring connecting piece is in an open cavity box shape, the lower portion of the anchoring connecting piece is provided with an opening, the opening is aligned with the wall body, and two sides of the anchoring connecting piece are welded and connected with the longitudinal anchoring steel bar.

Further, the specific method for vertically splicing the anchoring connecting pieces comprises the following steps: and (3) setting slurry with fine stone concrete on the frosted surface of the end part of the wall body just before the upper wall body unit is completely sunk. When the upper wall body is aligned and installed, alignment and splicing of the two wall body connecting pieces are guaranteed. After the high-strength connecting steel bars penetrate through the reserved hole channels and are inserted into the connecting pieces, the high-strength connecting steel bars are sleeved with the bolt base plates and are screwed down by the high-strength bolts, after all the connecting pieces and the high-strength connecting steel bars are anchored by the bolts, the connecting piece cavities are filled with fine concrete, the wall sinking is continued, and the like is performed on the subsequent vertical wall splicing.

Furthermore, the wall body unit is provided with a pre-embedded prestressed corrugated pipe throughout the length, and after the vertical whole continuous wall is completely sunk, prestressed ribs are stretched and the pre-embedded corrugated pipe is grouted.

Further, when the underground continuous wall is hung, the earth-digging machine is arranged in the cavity of the wall body, the wall is sunk while the earth is dug, when the lower wallboard unit is to be sunk completely, the upper wallboard unit is vertically spliced, and the whole vertical wall-sinking construction is completed by analogy in sequence.

Furthermore, during horizontal splicing, the prefabricated wall units are aligned with the sunk wall body through the positioning section steel, and the wall sinking is completed in the mode.

Furthermore, the wall side is provided with an uneven interface to increase a water seepage path, after the left continuous wall and the right continuous wall are completely sunk, soil in the middle of the lateral groove is cleaned to form a grouting cavity, and micro-expansion early-strength high-ductility cement-based material is used for grouting, wherein the micro-expansion early-strength high-ductility cement-based material has the same strength as the concrete of the prefabricated continuous wall.

Comprehensively, the utility model discloses form by the horizontal and vertical concatenation of a plurality of prefabricated continuous wall body unit. The cross section of each prefabricated underground continuous wall body unit is in a hollow square shape, the left side and the right side of each prefabricated underground continuous wall body unit are provided with a through long groove and embedded positioning section steel, the upper end and the lower end of each prefabricated underground continuous wall body unit are provided with a plurality of connecting pieces anchored with longitudinal ribs of the wall body unit, and prestressed corrugated pipes are vertically embedded in the wall body unit. The upper prefabricated wallboard unit and the lower prefabricated wallboard unit are spliced through the connecting piece and the high-strength connecting steel bars in an aligning mode, are screwed up through bolts, and stretch the prestressed ribs through the corrugated pipes after the vertical whole wall sinking is finished, so that the whole bending rigidity and the waterproof performance of the horizontal joint are good. Two adjacent horizontal prefabricated wall units are occluded through the positioning embedded profile steel, and after the lateral grooves of the left wall body and the right wall body are spliced to form a grouting cavity, a high-performance cement-based composite material is injected, so that cracking can be effectively reduced, and the waterproof performance is enhanced. The square-shaped section can be internally provided with machinery for driving a wall to sink when digging soil, so that the working procedures are reduced.

Has the advantages that: the assembled grid underground continuous wall of this application dry-type connection has following advantage:

1. the utility model discloses assembled underground continuous wall adopts automatic streamlined production, and size precision is high. The prefabricated building block can realize factory prefabrication and field installation, accords with the trend of building industrialization, and can effectively save materials, reduce pollution caused by construction and reduce labor cost;

2. the excavation and hoisting are convenient, the on-site construction is mainly realized by bolt dry connection, the working procedures of hole cleaning, wall brushing, cast-in-place and the like are reduced, the construction period is not influenced by post-pouring operation, the engineering efficiency is high, the main ribs between the vertical wall units are reliably connected and work cooperatively, and a good force transmission effect is realized;

3. compared with a solid-web traditional underground continuous wall, the section of the grille type cavity is high in bending rigidity, a large amount of cost and dead weight can be saved, and a rapid construction process of excavating and sinking the wall can be realized;

4. the main reinforcements between the vertical wall units are connected through bolts and connecting pieces, and simultaneously, the prestressed reinforcements are used for tensioning, so that the cooperative bending resistance of the vertical whole wallboard can be effectively realized, and the reliability of connection between the wallboards is ensured. After the sanding mortar-setting interface is subjected to prestress tensioning, the upper wall unit and the lower wall unit can be tightly occluded, and the waterproof capability of the wall unit is enhanced;

5. the left continuous wall and the right continuous wall are connected by adopting micro-expansion early-strength high-ductility cement-based composite material grouting, the high-ductility cement-based composite material has excellent deformation capacity and crack control capacity, excellent anti-cracking performance and tensile strength, and meanwhile, the wall side is provided with an uneven interface to increase a permeation path, so that the waterproof and anti-seepage performance of the dry-connected assembled grid underground continuous wall is improved;

6. the utility model discloses prefabricated underground continuous wall adopts automatic streamlined production, and size precision is high. The prefabricated building block can be prefabricated in a factory and installed on site, accords with the trend of building industrialization, and can effectively save materials, reduce pollution caused by construction and reduce labor cost.

Drawings

FIG. 1 is a schematic view of an underground diaphragm wall assembly of the present application;

FIG. 2 is a schematic cross-sectional view of a wall element and transverse connections according to the present application;

FIG. 3 is a schematic view of a steel joint of the present application;

FIG. 4 is a schematic view of a vertical connection section of the present application;

FIG. 5 is a schematic view of the vertical splice front of the present application.

Detailed Description

The present application is described in detail below with reference to specific embodiments and the attached drawings.

The dry-type connected assembly type grid underground continuous wall shown in the figure 1 is formed by transversely and longitudinally splicing a plurality of prefabricated wall units 1, and stirrups 14 and longitudinal ribs 5 are arranged inside the prefabricated wall units 1. The cross section of each prefabricated wall unit 1 is in a shape like a hollow square, the length of the cross section of each prefabricated wall unit 1 is 1800mm, the width of each prefabricated wall unit is 1200mm, and the wall thickness of each square is 200mm and 300 mm. The left side and the right side of the prefabricated wall unit 1 are provided with a through long groove 12 and embedded positioning section steel 2, the upper end and the lower end of the prefabricated wall unit are provided with a plurality of anchoring connecting pieces 4 anchored with the wall unit longitudinal ribs 5 and exposed connecting longitudinal ribs, and the anchoring connecting pieces and the exposed connecting longitudinal ribs are arranged on the splicing surfaces in a staggered mode. Referring to fig. 3, 4 and 5, the anchoring connector 4 is made of a Q335 steel plate, is in the shape of an open cavity box, and is welded and anchored at two sides with the wall longitudinal ribs 5, and the connecting end is through and corresponds to the wall reserved hole 13.

The specific method of vertical splicing is as follows: before upper portion wall body unit is about to sink completely, sit thick liquid 3 with the pea gravel concreten in the thick liquid interface to wall body tip mill hair, when upper portion wall body counterpoint installation, guarantee that the connecting reinforcement 6 that excels in of two wall bodies and anchor connecting piece 4 counterpoint the concatenation, concrete operation is: after the high-strength connecting steel bars 6 penetrate through the reserved hole 13 of the wall body and are inserted into the connecting pieces 4, the high-strength connecting steel bars are sleeved with the bolt backing plates 10 and are screwed down by the high-strength bolts 8, after all the anchoring connecting pieces 4 are anchored with the high-strength connecting steel bars 6, the connecting piece cavities are filled with the fine concrete 7, the wall continues to be sunk, and the like is performed in the subsequent vertical wall body splicing process. The wall body unit is further provided with a pre-buried stress corrugated pipe 8, and after the vertical whole continuous wall is completely sunk, the prestressed ribs are stretched and the pre-buried stress corrugated pipe 8 is grouted. When the underground continuous wall is hung, the earth digging machine is arranged in a wall cavity, the wall is sunk while the earth is dug, when the lower wallboard unit 1 is to be sunk completely, the vertical splicing upper wallboard unit 1 is sequentially analogized to complete the vertical whole-width wall sinking construction.

Referring to fig. 2, during horizontal splicing, the prefabricated wall units are aligned with the sunk wall embedded positioning section steel II 2-2 through the embedded positioning section steel I2-1, after the left and right continuous walls are sunk, soil in the middle of the lateral grooves 12 is cleaned to form a grouting cavity, and grouting is performed by using a micro-expansion early-strength high-ductility cement-based material 11, wherein the strength of the micro-expansion early-strength high-ductility cement-based material 11 is 30-60MPa, which is the same as that of concrete of the prefabricated continuous walls. The wall side is provided with a concave-convex interface 15 to increase the groundwater infiltration path. The ductility and mechanical property parameters of the micro-expansion early-strength high-ductility cement-based material 11 are related to the mixing ratio, and the manufacturing method of the high-ductility cement-based composite material with the shaping strength of 40MPa comprises the following steps: cement in the matrix: the fly ash is 1:2, the water-cement ratio is controlled to be 0.3, the sand-cement ratio is 0.2, and a certain amount of PVA fiber and silica fume are added, so that the prepared high-ductility cement-based material has 2-4% of tensile strain, 3-6MPa of tensile strength, 30-60MPa of compressive strength and good anti-permeability and anti-cracking performance.

The dry-connected assembled grid underground continuous wall support is generally suitable for soft soil areas, and can be smoothly pressed into soil bodies; the applicable depth of the foundation pit is generally not more than 25m, and special research and demonstration should be carried out on the ultra-deep foundation pit. When the assembled grid underground continuous wall supporting structure in dry connection is adopted, the deformation of the supporting structure and the surrounding environment is calculated, the deformation of the foundation pit and the surrounding environment meets the control requirements of protected objects in foundation pit engineering design, underground structure design and the surrounding environment, and the deformation limit value of the supporting structure is determined according to the factors of the importance of the surrounding environment, the adaptability to deformation, the property of soil and the like.

The pouring process of the dry-connected assembled type grid underground continuous wall comprises the following steps:

1. and (3) building a template, cleaning the surface, coating a release agent, and combining a steel mold at the end part with side and bottom wood molds for pouring each prefabricated part. The steel mould at the end part is accurately holed at the corresponding position, so that the steel bar connecting piece 4 and the high-strength connecting steel bar 6 are fixed on the steel mould in advance through bolts;

2. after positioning and fixing are completed, the reinforcement cage is manufactured and welded and fixed with the steel connecting piece, the side wood grinding tool is placed and fixed at a corresponding position, and a connecting box of the reinforcement connecting piece is blocked by foam;

3. the pouring of concrete is gone on in the prefabricated component factory, adopts the vibrting spear to vibrate when pouring closely knit, and the top surface adopts artifical rendering, notices the position that spills the connecting piece when rendering, avoids the shutoff. And covering the top surface with a plastic film after finishing plastering, and covering a steam cover for maintenance after pouring is finished and standing for a period of time.

The assembly process of the dry-connected assembly type grid underground continuous wall comprises the following steps:

1. hoisting the assembled grid underground continuous wall body unit in dry connection, and vertically placing the cavity of the prefabricated wall body on the slotting triple mixer in an aligned mode;

2. and starting the triple mixer for slotting and excavating to drive the prefabricated wall to sink, and lifting the vertical second wall when the wall is not completely sunk. Aligning and installing an upper wall unit and a lower wall unit;

3. when the upper and lower wall bodies are installed in an aligned mode, the interface is treated by mortar sitting, and meanwhile, the aligned splicing of the connecting pieces 4 of the two wall bodies is guaranteed. After the high-strength connecting steel bars 6 penetrate through the reserved hole channels 13 and are inserted into the connecting pieces, bolt backing plates 10 are sleeved on the connecting pieces, the connecting pieces are screwed by high-strength bolts 9, after all the connecting pieces 4 and the high-strength connecting steel bars 6 are anchored by the bolts, the connecting piece cavities are filled by using fine concrete 7, and then the wall sinking is continued;

4. assembling the next wall unit according to the process, arranging pre-embedded prestressed corrugated pipes 8 on the entire length of the wall unit, and stretching prestressed ribs and grouting the pre-embedded prestressed corrugated pipes 8 after the vertical whole continuous wall is completely sunk;

5. when horizontally spliced, the prefabricated wall units are aligned with a sunk wall body through the positioning section steels 2-1 and 2-2, after the left continuous wall and the right continuous wall are sunk to the wall, soil in the middle of the lateral groove 12 is cleaned to form a grouting cavity, and the micro-expansion early-strength high-ductility cement-based material 11 with the same concrete strength of the prefabricated continuous wall is used for grouting. And the installation of the next wall is finished by parity of reasoning.

The construction key points of the assembled type grid underground continuous wall adopting dry connection are as follows:

before excavation of foundation pit earthwork, an earthwork construction unit needs to compile a detailed construction organization scheme, and the construction unit, the supervision unit, the foundation pit support design unit and the social functional department can carry out construction after the construction unit, the supervision unit, the foundation pit support design unit and the social functional department are checked together and approved.

Before formal excavation, the foundation pit is drained and dewatered. The first concrete support strength reaches more than 70%, and soil below the support can be excavated.

In the excavation process, the partition, the block division, the layering, the symmetry and the balance are carried out, and the principle of firstly supporting and then excavating and strictly forbidding over-excavation is adhered to. The slope of the soil slope of the block depth platform is not less than 1: 1, the height difference is not more than 3.0 m.

When the earth is excavated along the unloading of the inner side of the support, the support construction unit needs to closely patrol and observe, under special conditions, experienced support construction personnel should command the excavation on site, and the earthwork construction unit should listen to the command on site.

During the excavation, the support construction unit needs to make emergency plan preparation, including personnel, equipment, materials, technical measures and the like, and once local leakage or large deformation occurs, measures are taken in time, and the earthwork construction unit needs to give comprehensive cooperation.

And (3) strictly forbidding piling a large amount of soil or building materials on the slope top of the foundation pit, if temporary piling is required, the height of the piled soil is not more than 1.0m, the grounding load of the materials is not more than 20kPa, and the distance from the side of the foundation pit to the side of the foundation pit is not less than 2.0 m.

And (4) strengthening foundation pit monitoring during excavation, if abnormal conditions occur, stopping excavation and timely processing.

The quality inspection and acceptance of the assembled grid underground continuous wall supporting structure in dry connection are divided into three stages of construction process monitoring, quality acceptance and foundation pit excavation inspection.

The construction process monitoring content of the assembled grid underground continuous wall supporting structure in dry connection comprises the following steps: and verifying the construction mechanical property, the material quality, the appearance, the positioning, the length, the elevation, the verticality and the like of the construction mold.

The quality acceptance of the assembled grid underground continuous wall supporting structure in dry connection is preferably divided into a plurality of inspection batches according to construction sections, and except for the wall strength inspection project, each inspection batch is at least 20 percent of the number of single wall bodies and is not less than 10. The quality acceptance procedure and organization of the inspection lot should meet the relevant regulations of the unified Standard for construction quality acceptance of building engineering GB 50300; and the qualification judgment of the inspection batch is in accordance with the relevant regulations of 'construction quality acceptance criteria for foundation engineering of building foundation' GB 50202.

The quality and the water leakage condition of the wall body of the excavation surface are emphatically checked during excavation of the foundation pit, and remedial measures are immediately taken if the quality and the water leakage condition are not in accordance with the design requirements.

Quality acceptance of branch projects such as a supporting system of a dry-type connected assembled grid underground continuous wall supporting structure and earthwork excavation should be carried out according to relevant regulations of the standards of 'construction quality acceptance Standard of Foundation engineering of building foundation' GB50202 and the like.

Claims (6)

1. The dry-connected assembled type grid underground continuous wall is characterized by being formed by splicing prefabricated wall units (1), wherein the cross sections of the prefabricated wall units (1) are of hollow square-shaped structures, through-long grooves (12) and pre-embedded positioning section steels (2) are arranged on two sides of each prefabricated wall unit, and anchoring connecting pieces (4) are arranged at two ends of each prefabricated wall unit; the anchoring connecting piece (4) is in an open cavity box shape, two sides of the anchoring connecting piece are anchored with the wall longitudinal ribs (5), and the connecting end is communicated with and corresponds to the wall reserved hole channel (13); the connecting ends of the vertically adjacent prefabricated wall units (1) are aligned, spliced and anchored by the high-strength connecting steel bars (6) and the connecting ends of the anchoring connecting pieces (4) are anchored; transversely adjacent prefabricated wall units are occluded through the pre-buried positioning section steel (2), so that after the lateral grooves (12) are spliced to form grouting holes, the micro-expansion early-strength high-ductility cement-based composite material (11) is filled.

2. A dry-connect fabricated grid underground continuous wall as claimed in claim 1, wherein the anchor connections (4) are made of Q335 steel plates distributed near the splicing faces of the prefabricated wall units ends.

3. The dry-connected fabricated grating underground continuous wall as claimed in claim 1, wherein the prefabricated wall units (1) have cross-sectional length of 1200-1800mm, width of 900-1200mm and wall thickness of 200-300 mm.

4. A dry-connected fabricated grating diaphragm wall as claimed in claim 1, wherein the prefabricated wall units (1) are provided with pre-embedded prestressed corrugated pipes (8) throughout their length.

5. A dry-connect fabricated grid underground diaphragm wall as claimed in claim 1, wherein the prefabricated wall units (1) are provided with a relief interface (15) on the wall side.

6. A dry-joined fabricated grid underground continuous wall as claimed in claim 1, wherein the micro-expansive early strength high ductility cement-based composite material (11) and the precast continuous wall concrete have a strength of 30 to 60 MPa.

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