CN114855884A - Construction method facilitating early backfill of post-cast strip of underground foundation structure - Google Patents

Construction method facilitating early backfill of post-cast strip of underground foundation structure Download PDF

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CN114855884A
CN114855884A CN202210646387.2A CN202210646387A CN114855884A CN 114855884 A CN114855884 A CN 114855884A CN 202210646387 A CN202210646387 A CN 202210646387A CN 114855884 A CN114855884 A CN 114855884A
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foundation
post
cast strip
brick
pouring
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CN114855884B (en
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王成民
张晓五
宋俊杰
张冲
徐友修
杨波
陈国鑫
余新友
阮明
张泽
陈进
童强
朱武
汤华明
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General Contracting Branch Of Anhui Construction Engineering Group Co ltd
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    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02DFOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D29/00Independent underground or underwater structures; Retaining walls
    • E02D29/16Arrangement or construction of joints in foundation structures
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02DFOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D15/00Handling building or like materials for hydraulic engineering or foundations
    • E02D15/02Handling of bulk concrete specially for foundation or hydraulic engineering purposes
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02DFOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D17/00Excavations; Bordering of excavations; Making embankments
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02DFOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D17/00Excavations; Bordering of excavations; Making embankments
    • E02D17/02Foundation pits
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02DFOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D17/00Excavations; Bordering of excavations; Making embankments
    • E02D17/02Foundation pits
    • E02D17/04Bordering surfacing or stiffening the sides of foundation pits
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02DFOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D17/00Excavations; Bordering of excavations; Making embankments
    • E02D17/18Making embankments, e.g. dikes, dams
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02DFOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D27/00Foundations as substructures
    • E02D27/10Deep foundations
    • E02D27/12Pile foundations
    • E02D27/14Pile framings, i.e. piles assembled to form the substructure
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02DFOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D3/00Improving or preserving soil or rock, e.g. preserving permafrost soil
    • E02D3/02Improving by compacting
    • E02D3/046Improving by compacting by tamping or vibrating, e.g. with auxiliary watering of the soil
    • EFIXED CONSTRUCTIONS
    • E02HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02DFOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
    • E02D3/00Improving or preserving soil or rock, e.g. preserving permafrost soil
    • E02D3/02Improving by compacting
    • E02D3/10Improving by compacting by watering, draining, de-aerating or blasting, e.g. by installing sand or wick drains
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06FELECTRIC DIGITAL DATA PROCESSING
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Abstract

The invention discloses a construction method convenient for backfilling an underground foundation structure post-cast strip in advance, which comprises the following steps: calculating the section size bearing capacity of the brick pier; after the foundation pit is excavated to the designed elevation, pouring a cushion layer, building brick piers to be 2-3 cm away from the bottom surface of the foundation beam after the cushion layer reaches certain strength, and plastering and leveling the top surfaces of the brick piers to be used as a foundation beam bottom mould; pouring a foundation cushion cap, after the pouring of the foundation cushion cap is finished and the dismantling requirement is met, erecting a foundation beam scaffold support, laying a foundation beam template and a column template, and pouring a column and foundation beam concrete after the template is well reinforced; after the foundation beam of the post-cast strip meets the requirement of form removal, the scaffold support is removed, and the upper opening of the post-cast strip is closed; backfilling foundation pit soil to a required position, and performing ground structure construction after backfilling; and after the post-cast strip reaches the sealing time, opening the sealed wood cover plate, roughening and wetting the post-cast strip, and then pouring. The invention can carry out the backfill operation of the foundation pit in advance and greatly shortens the construction period.

Description

Construction method facilitating early backfill of post-cast strip of underground foundation structure
Technical Field
The invention relates to a construction method for facilitating early backfilling of a post-cast strip of an underground foundation structure, and belongs to the technical field of constructional engineering.
Background
In the construction process, a post-cast strip is reserved for buildings with the size exceeding a certain scale and is used for preventing harmful cracks of a reinforced concrete structure due to uneven temperature and shrinkage. The post-cast strips are arranged in the corresponding beam plates from the foundation to the roof. Generally, the construction of a settlement post-cast strip is finished in a main building structure, and the settlement rate tends to be stable for one month; the post-shrinkage casting strip should be closed after the concrete age on both sides reaches 60 days. The required support system is in principle not removable until the post-cast strip is not closed. In the construction process, the sealing time of the post-cast strip of the underground foundation structure part is long, so that the backfilling time of the foundation pit is too long, and the construction period is seriously influenced. In order to shorten the construction period, some construction units directly backfill the steel pipes which are not dismantled at the post-cast strip, and the steel pipes are subjected to uneven lateral pressure of backfill soil during backfilling, so that the steel pipes are easy to bend and deform, and great potential safety hazards are caused.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides the construction method which is convenient for the early backfilling of the post-cast strip of the underground foundation structure, and is suitable for the underground foundation structure without a basement or a first-layer structural slab; before the post-cast strip of the underground foundation structure is not closed, the supporting systems at other parts except the post-cast strip can be detached, foundation pit backfill operation is carried out in advance through the post-cast strip supporting structure, and the stability and the safety of the post-cast strip can be ensured.
In order to achieve the purpose, the construction method for conveniently backfilling the post-cast strip of the underground foundation structure in advance comprises the following steps:
s1, calculating the section size bearing capacity of the brick pier;
s2, after the foundation pit is excavated to the designed elevation, pouring a cushion layer, wherein the cushion layer is 100mm thick C15 plain concrete, after the cushion layer reaches a certain strength, building brick piers to be 2-3 cm away from the bottom surface of the foundation beam, plastering and leveling the top surfaces of the brick piers to be used as a bottom mould of the foundation beam, and filling the position of a post-cast strip to be 100mm lower than the bottom surface of the foundation beam;
s3, pouring a foundation pile cap, after the foundation pile cap is poured and meets the dismantling requirement, erecting a foundation beam scaffold support, laying a foundation beam template and a column template, and pouring a column and foundation beam concrete after the template is well reinforced;
s4, after the post-cast strip foundation beam meets the form removal requirement, removing the scaffold support, and sealing the upper opening of the post-cast strip;
s5, backfilling foundation pit soil to a required position, and performing ground structure construction after backfilling;
and S6, opening the closed wood cover plate after the post-cast strip reaches the closing time, roughening and wetting the post-cast strip, and pouring.
As an improvement, in the step S1, the sectional length of the brick pier is firstly determined preliminarily according to the sum of the post-cast strip and the sectional widths of the beams on both sides, the width of the brick pier is firstly determined preliminarily according to the width of the beam section expanded by 200mm, and then load calculation and the calculation of the bearing capacity of the compression member of the non-reinforced masonry are performed to determine the size of the final brick pier.
As an improvement, after the foundation pit is excavated to the designed elevation in the step S2, the foundation and beam position lines are released, the foundation cushion, the scaffold cushion and the brick pier cushion are poured, the cushion is a C15 plain concrete with the thickness of 100mm, after the cushion strength reaches a certain strength, the brick piers are built to be 2 to 3cm away from the bottom surface of the foundation beam, the top surfaces of the brick piers are plastered and leveled to be used as a bottom die forming die of the foundation beam, the dust accumulation pit on the brick piers at the position of the post-cast strip is 100mm lower than the bottom surface of the foundation beam, and a 10mm PVC casing is reserved at the dust accumulation pit.
As an improvement, in step S3, a foundation cap is poured, after the foundation cap is poured and the dismantling requirement is met, a foundation beam scaffold support is set up, the scaffold support includes a cross brace, a foundation beam template and a column template are laid, the foundation beam template is separately supported at the position of a brick pier, the column is reinforced by a steel pipe and a first counter-pull screw, the beam is reinforced by a steel pipe and a second counter-pull screw, and the column and the foundation beam concrete are poured.
In step S4, after the foundation beams on both sides of the post-cast strip meet the form removal requirement, the scaffold support is removed, the brick piers and the post-cast strip form are retained, and the upper opening of the post-cast strip is closed by the wooden cover plate.
As an improvement, after the post-cast strip reaches the sealing time in the step S6, the sealed wood cover plate is opened, the post-cast strip is roughened and sundries are cleaned, the roughened and cleaned sundries are directly left in the ash accumulation pit, excess water permeates into soil from the PVC casing pipe, and finally pouring is performed.
Compared with the prior art, the brick piers are built at the post-cast strip of the foundation beam, the foundation pit backfilling operation can be performed in advance under the condition that the post-cast strip support is not removed, the construction period is greatly shortened, and meanwhile, the stability and the safety of the post-cast strip in the whole construction process are improved by the brick pier supporting structure.
Drawings
FIG. 1 shows the dimensions of an embodiment 1 of the invention;
FIG. 2 is a graph illustrating the range of different gamma values;
FIG. 3 is a schematic view of a blanket of the present invention;
FIG. 4 is a schematic view of the brick pier construction of the present invention;
FIG. 5 is a schematic view of the construction of the formwork supports on both sides of the post-cast strip according to the present invention;
FIG. 6 is a schematic view of a portion of the structure of FIG. 5;
FIG. 7 is a schematic diagram of a post-cast strip template structure of the present invention;
FIG. 8 is a schematic illustration of the scaffold support of the present invention removed;
FIG. 9 is a schematic view of the earth of the present invention after backfilling;
in the figure: 1. 100mm thick C15 plain concrete, 2, basic cushion cap, 3, brick pier structure, 31, brick pier, 32, ash deposition pit, 33, PVC sleeve, 4, scaffold support, 5, post template system, 51, post template, 52, counter-pull screw rod I, 53, post, 6, basic beam template system, 61, basic beam template, 62, basic beam concrete, 63, counter-pull screw rod II, 7, post-cast strip template system, 71, post-cast strip post-cast basic beam, 72, post-cast strip template, 73, wood cover plate, 8, foundation pit soil.
Detailed Description
The following examples are further illustrative of the present invention as to the technical content of the present invention, but the essence of the present invention is not limited to the following examples, and one of ordinary skill in the art can and should understand that any simple changes or substitutions based on the essence of the present invention should fall within the protection scope of the present invention.
A construction method convenient for early backfilling of a post-cast strip of an underground foundation structure comprises the following steps:
s1, calculating the section size bearing capacity of the brick pier 31;
s2, after the foundation pit is excavated to a designed elevation, pouring a foundation cushion layer, a scaffold cushion layer and a brick pier cushion layer, wherein the cushion layer is 100mm thick C15 plain concrete 1, after the strength of the cushion layer reaches a certain strength, building brick piers 31 to be 2-3 cm away from the bottom surface of a foundation beam, plastering and leveling the top surfaces of the brick piers 31 to be used as a foundation beam bottom die moulding bed, the section width of each brick pier 31 is 200mm larger than the width of the foundation beam, the length of each brick pier is the sum of two times of the beam section width and the width of a post-cast strip, and the position of the post-cast strip is filled to be 100mm lower than the bottom surface of the foundation beam;
s3, pouring the foundation bearing platform 2, after the foundation bearing platform 2 is poured and meets the dismantling requirement, erecting a foundation beam scaffold support 4, laying a foundation beam template 61 and a column template 51, reinforcing the templates, and pouring a column 53 and foundation beam concrete 62 (post-pouring of a post-pouring belt part);
s4, after the post-cast strip foundation beam meets the form removal requirement, removing the scaffold support 4 and sealing the upper opening of the post-cast strip;
s5, backfilling foundation pit soil 8 to a required position, generally backfilling to a position of a solid paved terrace foundation layer, determining a specific elevation according to a project construction method, backfilling and tamping backfilled soil in a layering manner, backfilling the opposite two sides or four sides of the brick pier 31 symmetrically and simultaneously, and performing ground structure construction after backfilling;
and S6, opening the closed wood cover plate 73 after the post-cast strip reaches the closing time, roughening and wetting the post-cast strip, and pouring the post-cast strip post-cast foundation beam 71.
In a preferred embodiment, in step S1, the sectional length of the brick pier 31 is initially determined according to the sum of the post-cast strip and the sectional widths of the two side beams, the width of the brick pier is initially determined according to the beam sectional width expanded by 200mm, and then load calculation and the calculation of the bearing capacity of the compression member of the unbanded masonry are performed to determine the final brick pier size. The determination of the size of the brick pier 31 in the brick pier structure 3 not only considers whether the load-bearing foundation beam meets the requirements, but also considers the construction measure requirements of the foundation beam template and the subsequent pouring post-cast strip.
As a preferred embodiment, after the foundation pit is excavated to the designed elevation in the step S2, the independent foundation (foundation bearing platform) and the vertical projection position line of the foundation beam are released, the foundation pad, the scaffold pad and the brick pier pad are poured, the pad is a 100mm thick C15 plain concrete 1, the brick pier 31 is built to 2 to 3cm away from the bottom surface of the beam after the pad strength reaches a certain strength, the top surface of the brick pier 31 is plastered and leveled to be used as a bottom die mould of the foundation beam, the section width of the brick pier is 200mm greater than the width of the foundation beam, the length of the brick pier is the sum of two times of the section width of the beam and the width of a post-cast strip, the ash accumulation 32 on the brick pier 31 is 100mm lower than the bottom surface of the foundation beam, and a 10mm pvc casing 33 is reserved at the ash accumulation pit 32. The brick pier 31 is built before the foundation bearing platform 2 is poured, so that the brick pier 31 has more sufficient maintenance time, the strength can meet the requirement earlier, and a foundation beam is not delayed to be supported; the top surfaces of the bricks are plastered and leveled to be used as a base beam moulding bed, so that materials are fully utilized, and a wood template is saved; a dust accumulation pit 32 is reserved at the post-cast strip of the brick pier 31, aiming at roughening the construction joint of the post-cast strip in the later period under the condition that a side mould of the post-cast strip is not removed, remaining sundries after roughening in the dust accumulation pit 32 and paying attention to the fact that the sundries are forbidden to exceed the bottom surface of the top of the foundation beam; a10 mm PVC sleeve 33 is reserved at the position of the ash accumulation pit 32, so that watering and moistening are carried out before the post-cast strip is closed, and redundant accumulated water permeates into soil through the PVC sleeve 33.
As a preferred embodiment, the foundation cap 2 is poured in step S3, after the foundation cap 2 is poured and the dismantling requirement is met, the foundation beam scaffold 4 is set up, the scaffold 4 should include a cross brace, the foundation beam form 61 in the foundation beam form system 6 and the pillar form 51 in the pillar form system 5 are laid, the foundation beam form 61 is separately supported at the position of the brick pier 31, the post-cast strip form system 7 is an independent system, the pillar 53 is reinforced by the steel pipe and the first counter screw 52, the reinforcing member may also be a shaped stirrup, the beam is reinforced by the steel pipe and the second counter screw 63, and the pillar 53 and the foundation beam 62 are poured. The scaffold support 4 is to be safely calculated and used after meeting the requirements.
In a preferred embodiment, in the step S4, after the foundation beams on both sides of the post-cast strip meet the requirement of form removal, the scaffold support 4 is removed, the brick piers 31 and the post-cast strip form plates 72 are reserved, and the upper opening of the post-cast strip is closed by the wood cover plate 73.
As a preferred embodiment, after the post-cast strip is closed for the closing time in step S6, the closed wooden cover plate 73 is opened, the post-cast strip is roughened and sundries are cleaned, the roughened and cleaned sundries are directly left in the ash accumulation pit 32, the left sundries cannot exceed the bottom surface of the foundation beam and are sprayed with water to be wet, and excess water permeates into soil from the PVC casing 33, and finally pouring is performed. And if the elevation of the backfill is lower than the bottom surface of the foundation beam and the height of the beam section is higher, opening the side die of the post-cast strip to clean the construction joint of the post-cast strip.
Example 1
As shown in fig. 1 to 9, a construction method for facilitating early backfill of a post-cast strip of an underground foundation structure includes the steps of:
s1, calculating the section size bearing capacity of the brick pier 31;
s11, load calculation, as in table 1:
TABLE 1 load calculation
Template and standard value G of self-weight of support thereof 1k (kN/m 2 ) 0.1
Newly-poured concrete dead weight standard value G 2k (kN/m 3 ) 24
Concrete beam steel bar dead weight standard value G 3k (kN/m 3 ) 1.5
Construction load standard value Q 1k (kN/m 2 ) 3
Coefficient of structural importance gamma 0 1
Beam height h in the present embodiment 0.7m
Beam width b of the embodiment 0.4m
Length of left main beam of post-cast strip 3.4m
Length of right main beam of post-cast strip 3.4m
S12, designing the load of the panel bearing beam section direction line:
q 1 =γ0×[1.3×(G 1k +(G 2k +G 3k )×h)+1.5×Q 1k ]×b=1×[1.3×(0.1+(24+1.5)×0.7)+1.5×3]×0.4=11.134kN/m;
the design value of the load of the left main beam of the post-cast strip is as follows: gz 11.134 × 3.4 — 37.8556 kN;
the design value of the load of the right main beam of the post-cast strip is as follows: gz 11.134 × 3.4 — 37.8556 kN;
s13, and referring to FIG. 1, calculating the bearing capacity of the compression member of the reinforcement-free masonry:
N l ≦γfA l
in the formula: n is a radical of l -design value of axial force on local compression area;
gamma-coefficient of improvement of local compressive strength of the masonry;
f-designed compression strength of the masonry with local compression area less than 0.3m 2 The influence of the intensity adjustment coefficient gamma may not be considered;
A l -local area under pressure;
in the embodiment of the invention, the cross section size of the brick pier 31 is 600mm x 1800mm, the width of the post-cast strip is 1000mm, and the cross section size of the structural beam is 400 x 700 mm. Local pressed area a of brick pier 31 l =0.4*0.4=0.16m 2 <0.3m 2 The influence of the intensity adjustment coefficient γ may not be considered. If the local pressure area is greater than or equal to 0.3m 2 In the following cases
Figure BDA0003686078050000061
Calculating gamma, A 0 The calculated area for influencing the local compressive strength of the masonry. To prevent sudden brittle failure of the masonry, the calculated gamma value should meet the following specifications, as shown in fig. 2:
1) in the case of the lower graph (a), γ ≦ 2.5;
2) in the case of the lower graph (b), γ ≦ 2.0;
3) in the case of the lower graph (c), γ ≦ 1.5;
4) in the case of the lower graph (d), γ ≦ 1.25;
the masonry brick of the embodiment adopts the mortar of the common sintered brick MU20 and M15, and f is 3.22Mpa according to the following table 2. A. the l =0.16m 2 ,N l =37.8556*10 3 /2=1.9*10 4 N<0.16*3.22*10 6 =51.52*10 4 . This embodiment meets the requirements, and for the convenience of the follow-up pouring of the template and the post-cast strip, the actual brick pier width is 200mm larger than the beam width, and the brick pier length is the sum of twice the beam section width and the post-cast strip width. And filling and building the post-cast strip position.
TABLE 2 compression Strength design values (MPa) for fired plain brick and fired perforated brick masonry
Figure BDA0003686078050000071
Note: when the porosity of the fired porous brick is more than 30%, the value in the table should be multiplied by 0.9.
S2, referring to fig. 3-4, after the foundation pit is excavated to the designed elevation, the foundation and beam position line is released, the foundation bed course, scaffold bed course and brick pier bed course are poured, the bed course is 100mm thick C15 plain concrete 1 (fig. 3), after the bed course reaches a certain strength, the brick piers 31 are built to the bottom surface of the foundation beam and the thickness of the template is reserved, the cross-sectional width of the brick piers 31 is 200mm larger than the width of the foundation beam, the length of the brick piers is the sum of the two times of the beam cross-sectional width and the width of the post-cast strip, the size of the brick piers 31 is 600mm 1800mm, the ash pit 32 of the brick piers 31 at the post-cast strip position is 100mm lower than the bottom surface of the foundation beam, and a 10mm PVC casing 33 (fig. 4) is reserved at the ash pit 32;
s3, referring to fig. 5-7, pouring the foundation cap 2, after the foundation cap 2 is poured and the dismantling requirement is met, erecting the foundation beam scaffold 4, laying the foundation beam form 61 and the pillar form 51, the foundation beam form 61 separately erecting the form at the brick pier 31, the post-cast strip form system 7 is an independent system, the pillar 53 is reinforced by the steel pipe and the first counter screw 52, the reinforcing member can also be a shaped stirrup, the beam is reinforced by the steel pipe and the second counter screw 63, and the pillar 53 and the foundation beam concrete 62 are poured;
s4, referring to FIG. 8, after the foundation beams on the two sides of the post-cast strip meet the requirement of form removal, the scaffold support 4 is removed, the brick piers 31 and the post-cast strip template 72 are reserved, and the upper opening of the post-cast strip is sealed by a wood cover plate 73;
s5, referring to the figure 9, backfilling foundation pit soil 8 to a required position, generally backfilling to a position of a solid paved terrace foundation layer, determining a specific elevation according to a project construction method, backfilling and tamping backfilled soil in layers, backfilling brick piers symmetrically and simultaneously on two opposite sides or four sides, and performing ground structure construction after backfilling;
and S6, after the post-cast strip is sealed for a certain time, opening the sealing wood cover plate 73, chiseling the post-cast strip and cleaning sundries, directly reserving the chiseling and cleaned sundries in the ash accumulation pit 32, enabling the reserved sundries not to exceed the bottom surface of the foundation beam, sprinkling water to moisten the foundation beam, enabling redundant water to permeate into soil from the PVC casing pipe 33, and finally pouring the post-cast strip post-cast foundation beam 71.
According to the invention, the brick piers are built at the post-cast strip of the foundation beam, so that the foundation pit backfilling operation can be carried out in advance under the condition that the post-cast strip support is not removed, the construction period is greatly shortened, and meanwhile, the stability and the safety of the post-cast strip in the whole construction process are improved by the brick pier supporting structure.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents or improvements made within the spirit and principle of the present invention should be included in the scope of the present invention.

Claims (6)

1. A construction method convenient for backfilling soil in advance of a post-cast strip of an underground foundation structure is characterized by comprising the following steps:
s1, calculating the section size bearing capacity of the brick pier (31);
s2, after the foundation pit is excavated to the designed elevation, pouring a cushion layer, wherein the cushion layer is 100mm thick C15 plain concrete (1), after the cushion layer reaches a certain strength, building brick piers (31) to be 2-3 cm away from the bottom surface of the foundation beam, plastering and leveling the top surfaces of the brick piers (31) to be used as a bottom die forming die of the foundation beam, and filling the position of a post-cast strip to be 100mm lower than the bottom surface of the foundation beam;
s3, pouring a foundation bearing platform (2), after the foundation bearing platform (2) is poured and meets the dismantling requirement, erecting a foundation beam scaffold support (4), paving a foundation beam template (61) and a column template (51), and pouring a column (53) and foundation beam concrete (62) after the template is reinforced;
s4, after the post-cast strip foundation beam meets the form removal requirement, removing the scaffold support (4), and sealing the upper opening of the post-cast strip;
s5, backfilling foundation pit soil (8) to a required position, and performing ground structure construction after backfilling;
and S6, opening the closed wood cover plate (73) after the post-cast strip reaches the closing time, roughening and wetting the post-cast strip, and pouring.
2. The construction method for facilitating early backfill of a post-cast strip of an underground foundation structure according to claim 1, wherein in the step S1, the section length of the brick pier (31) is preliminarily determined according to the sum of the post-cast strip and the section widths of the two side beams, the width of the brick pier is preliminarily determined according to the enlargement of the section width of the beam by 200mm, and then the final brick pier size is determined through load calculation and the calculation of the bearing capacity of the compression member of the unbanded masonry.
3. The construction method for facilitating the early backfill of the post-cast strip of the underground foundation structure according to claim 1, wherein the foundation pit is excavated to the designed elevation in the step S2, the foundation and beam position line is released, the foundation bed course, the scaffold bed course and the brick pier bed course are poured, the bed course is 100mm thick C15 plain concrete (1), the brick piers (31) are built to 2 to 3cm from the bottom surface of the foundation beam after the bed course strength reaches a certain strength, the top surface of the brick piers (31) is plastered and leveled to be used as a bottom die matrix of the foundation beam, the ash pit (32) on the brick piers (31) at the post-cast strip position is 100mm lower than the bottom surface of the foundation beam, and a 10mm PVC casing (33) is reserved at the ash pit (32).
4. The construction method for facilitating the early backfill of the post-cast strip of the underground foundation structure according to claim 1, wherein the step S3 is implemented by pouring the foundation bearing platform (2), after the pouring of the foundation bearing platform (2) is completed and the dismantling requirement is met, the foundation beam scaffold support (4) is erected, the scaffold support (4) comprises a cross brace, a foundation beam template (61) and a column template (51) are laid, the foundation beam template (61) is separately supported at the position of the brick pier (31), the column (53) is reinforced by a steel pipe and a first counter-pull screw rod (52), the beam is reinforced by a steel pipe and a second counter-pull screw rod (63), and the column (53) and the foundation beam concrete (62) are poured.
5. The construction method for facilitating early backfill of the post-cast strip of the underground foundation structure according to the claim 1, wherein in the step S4, after the foundation beams on the two sides of the post-cast strip meet the requirement of form removal, the scaffold supports (4) are removed, the brick piers (31) and the post-cast strip templates (72) are reserved, and the upper opening of the post-cast strip is closed by a wood cover plate (73).
6. The construction method for facilitating early backfill of the post-cast strip of the underground foundation structure according to claim 1, wherein after the post-cast strip reaches the sealing time in the step S6, the sealed wood cover plate (73) is opened, the post-cast strip is roughened and sundries are cleaned, the roughened and cleaned sundries are directly left in the ash accumulation pit (32), excessive water permeates into soil from the PVC sleeve (33), and finally pouring is carried out.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115301026A (en) * 2022-08-10 2022-11-08 安徽建工集团股份有限公司总承包分公司 Hanging type dust removal system and hanging type dust removal method

Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102561690A (en) * 2012-03-12 2012-07-11 中天建设集团有限公司 Construction method for supporting structures on two sides of post-cast strip by use of brick column
CN202416324U (en) * 2011-12-21 2012-09-05 上海建工一建集团有限公司 Beam and slab structure superposed through top-down beam and down-top slab construction of foundation pit project
CN105926657A (en) * 2016-06-20 2016-09-07 中国建筑第二工程局有限公司 Concrete foundation prefabricated slab and construction method thereof
CN206607602U (en) * 2017-03-09 2017-11-03 陈启品 A kind of new prefabricated section and new type of retaining system
JP2018059318A (en) * 2016-10-05 2018-04-12 株式会社竹中工務店 Foundation beam structure and method of constructing foundation beam
CN109736593A (en) * 2019-02-27 2019-05-10 广西大学 Underground engineering group cheats mid-board and cuts method
CN110258651A (en) * 2019-07-16 2019-09-20 中城投集团第六工程局有限公司 Basement roof post-cast strip shifts to an earlier date enclosed construction and construction method
CN110700268A (en) * 2019-10-14 2020-01-17 中国十七冶集团有限公司 Construction method for backfilling foundation pit at post-cast strip of basement wall plate in advance
CN111691468A (en) * 2020-06-28 2020-09-22 上海东方雨虹防水工程有限公司 Pile head waterproof structure and construction method thereof
CN213174787U (en) * 2020-08-25 2021-05-11 上海宝冶建筑工程有限公司 High-low span column concrete pouring template
CN213597490U (en) * 2020-10-26 2021-07-02 上海宝冶集团有限公司 Post-cast strip strutting arrangement
CN114016552A (en) * 2021-11-18 2022-02-08 中铁十二局集团建筑安装工程有限公司 Pre-sealing construction method for basement roof settlement post-cast strip
CN215926411U (en) * 2021-08-17 2022-03-01 中国建筑第八工程局有限公司 Narrow space post-cast strip formwork device in advance
CN114412168A (en) * 2021-12-21 2022-04-29 成都建工第四建筑工程有限公司 Construction method of post-cast strip for supporting and settling reinforced concrete column

Patent Citations (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN202416324U (en) * 2011-12-21 2012-09-05 上海建工一建集团有限公司 Beam and slab structure superposed through top-down beam and down-top slab construction of foundation pit project
CN102561690A (en) * 2012-03-12 2012-07-11 中天建设集团有限公司 Construction method for supporting structures on two sides of post-cast strip by use of brick column
CN105926657A (en) * 2016-06-20 2016-09-07 中国建筑第二工程局有限公司 Concrete foundation prefabricated slab and construction method thereof
JP2018059318A (en) * 2016-10-05 2018-04-12 株式会社竹中工務店 Foundation beam structure and method of constructing foundation beam
CN206607602U (en) * 2017-03-09 2017-11-03 陈启品 A kind of new prefabricated section and new type of retaining system
CN109736593A (en) * 2019-02-27 2019-05-10 广西大学 Underground engineering group cheats mid-board and cuts method
CN110258651A (en) * 2019-07-16 2019-09-20 中城投集团第六工程局有限公司 Basement roof post-cast strip shifts to an earlier date enclosed construction and construction method
CN110700268A (en) * 2019-10-14 2020-01-17 中国十七冶集团有限公司 Construction method for backfilling foundation pit at post-cast strip of basement wall plate in advance
CN111691468A (en) * 2020-06-28 2020-09-22 上海东方雨虹防水工程有限公司 Pile head waterproof structure and construction method thereof
CN213174787U (en) * 2020-08-25 2021-05-11 上海宝冶建筑工程有限公司 High-low span column concrete pouring template
CN213597490U (en) * 2020-10-26 2021-07-02 上海宝冶集团有限公司 Post-cast strip strutting arrangement
CN215926411U (en) * 2021-08-17 2022-03-01 中国建筑第八工程局有限公司 Narrow space post-cast strip formwork device in advance
CN114016552A (en) * 2021-11-18 2022-02-08 中铁十二局集团建筑安装工程有限公司 Pre-sealing construction method for basement roof settlement post-cast strip
CN114412168A (en) * 2021-12-21 2022-04-29 成都建工第四建筑工程有限公司 Construction method of post-cast strip for supporting and settling reinforced concrete column

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115301026A (en) * 2022-08-10 2022-11-08 安徽建工集团股份有限公司总承包分公司 Hanging type dust removal system and hanging type dust removal method

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