CN110889235A - Underground pile foundation construction engineering design method - Google Patents

Underground pile foundation construction engineering design method Download PDF

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Publication number
CN110889235A
CN110889235A CN201911231376.2A CN201911231376A CN110889235A CN 110889235 A CN110889235 A CN 110889235A CN 201911231376 A CN201911231376 A CN 201911231376A CN 110889235 A CN110889235 A CN 110889235A
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pile
pile foundation
foundation
design
underground
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郭建勋
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Jiangsu Jianheng Engineering Management Consulting Co Ltd
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Jiangsu Jianheng Engineering Management Consulting Co Ltd
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Abstract

The invention relates to a design method of underground pile foundation constructional engineering, which is characterized by comprising the following steps: step S1, early design; step S2, foundation reconnaissance and foundation model selection; step S3, pile size design; step S4, pile foundation calculation; step S5, pile foundation design; step S6, compiling a pile foundation calculation book, drawing a pile foundation plane layout, a pile foundation full-page design drawing, a drilling plane layout and a geological longitudinal section and pile bottom elevation design drawing; and S7, manufacturing the pile, and driving and connecting the pile foundation. The design method for the underground pile foundation building engineering, disclosed by the invention, has strong practicability, can effectively reduce the cost of manpower and material resources, improve the construction efficiency and shorten the construction period, and the underground pile foundation designed by the design method has better stability, stronger stress resistance and bearing capacity and low possibility of deformation or instability; the surplus of the structural bearing capacity and the waste of materials are avoided, the construction cost is lower, and the quality is better.

Description

Underground pile foundation construction engineering design method
Technical Field
The invention belongs to the technical field of constructional engineering, and particularly relates to a design method of underground pile foundation constructional engineering.
Background
With the continuous development of national economy, municipal engineering and building construction become important components of national infrastructure, the scale and requirements of the civil engineering and building construction are continuously developed towards high standards and high requirements, and underground pile foundation building engineering is a key object for municipal and building engineering construction. The underground pile foundation with excellent design performance and reasonable layout is one of important factors for the stability and good advance of the underground pile foundation building engineering.
The design of the pile foundation is to enhance the bearing capacity of the foundation to buildings, and the pile foundation is commonly applied to pile base materials arranged in the deep position of the foundation in a pile driving mode or a reinforced concrete pouring mode, particularly in coastal economically developed areas. However, in the prior art, the pile type is designed and calculated according to a homogeneous material, and for a friction pile, the problem that the structural bearing capacity determined by the pile material is not matched with the foundation bearing capacity of the pile determined by a soil body usually exists, and particularly, the pile body is enlarged to improve the foundation bearing capacity of the pile in soft soil, so that the structural bearing capacity of the pile is redundant and the material is wasted; on the other hand, the existing pile type has different pile body defects; in addition, in the existing grouting process, gaps among soil are filled with cement paste, so that the bearing capacity of the pile can be properly improved, but the calculated size of a pile body cannot be effectively increased.
Therefore, a more reasonable design method for underground pile foundation building engineering is sought, and the method has very important significance for improving the quality of the building engineering, reducing the cost of human and material resources, improving the construction efficiency and shortening the construction period.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a design method of underground pile foundation constructional engineering, which is reasonable, simple and feasible, has strong practicability, can effectively improve the quality of the constructional engineering, reduce the cost of manpower and material resources, improve the construction efficiency and shorten the construction period, and the underground pile foundation designed by the design method has better stability, stronger stress resistance and bearing capacity and low possibility of deformation or instability; the surplus of the structural bearing capacity and the waste of materials are avoided, the construction cost is lower, and the quality is better.
In order to achieve the purpose, the technical scheme adopted by the invention is as follows: a design method for underground pile foundation construction engineering comprises the following steps:
step S1, early design: designing according to the engineering construction project requirement, creating a WBS, and designing a safety guarantee system in the construction process of the underground pile foundation building engineering project, wherein the safety guarantee system comprises the integrity construction site guarantee safety and the construction process operation safety; designing construction quality and speed, and designing material, personnel and capital allocation;
step S2, foundation reconnaissance, foundation type selection: surveying the physical and mechanical performance parameters of foundation rock and soil, in-situ test parameters, underground water level conditions and seismic fortification intensity, determining the design grade of the foundation, the material of a pile foundation, the preliminary pile diameter and the plane of a distributed pile foundation according to JGJ 94-2008 'design Specification of building pile foundations';
step S3, pile size design: primarily estimating the section size, calculating the load of a pile foundation, determining the structural form of the pile foundation according to geological data and the load of the pile foundation, and reversely calculating the pile length and the pile bottom elevation according to rock-soil parameters and the load of the pile foundation so as to determine the pile bottom elevation; selecting a bearing stratum and determining the depth of a pile end entering the bearing stratum;
step S4, pile foundation calculation: calculating the bearing capacity of the pile foundation and determining the reinforcement of the pile foundation; determining the number, the spacing and the arrangement mode of the piles;
step S5, pile foundation design: looking up a map set through a calculation result and design requirements, and designing a pile body structure and a bearing platform of the pile body structure;
and S6, compiling a pile foundation calculation book, drawing a pile foundation plane layout, a pile foundation full-page design drawing, a drilling plane layout and a geological longitudinal section and pile bottom elevation design drawing.
And step S7, pile manufacturing, pile foundation driving and pile splicing.
In a preferred embodiment of the present invention, in step S2, the base design level is class c, and the pile foundation is made of PHC;
preferably, the principle of selecting the bearing stratum and determining the depth of the pile tip entering the bearing stratum is as follows: the depth of the full section of the pile end entering the bearing stratum is not less than 2d for cohesive soil and silty soil, not less than 1.5.5 d for sandy soil and not less than 1d for gravel soil. When a weak subjacent layer exists, the thickness of a hard bearing layer below the pile end is not smaller than 3d, wherein d is the embedding depth of the bearing platform.
Preferably, the burying depth of the bearing platform is not less than 700-800 mm.
Preferably, when the number of piles is determined in step S4, the number of piles is calculated according to the following formula: n is more than or equal to (Fk + Gk)/Ra (1.2-1.4) (considering bias), wherein Ra is the characteristic value of the estimated vertical bearing capacity of the single pile, Fk is the vertical force of a column root/a column top, and Gk is the dead weight of a bottom layer wall, a foundation beam, covering soil and a bearing platform.
Preferably, the arrangement manner in step S4 is to satisfy that the minimum center distance of the piles is greater than or equal to 4d, the minimum width of the pile foundation bearing platform under the independent column is not less than 600mm, the distance from the center of the side pile to the edge of the bearing platform is not less than the diameter or the side length of the pile, and the distance from the outer edge of the pile to the edge of the bearing platform is not less than 200 mm.
Preferably, the bearing platform is designed according to the pile foundation bearing platform atlas in the step S5.
Preferably, the structural form of the pile foundation is selected from one of an end bearing pile and a friction pile.
Preferably, in step S4, the pile foundation bearing capacity calculation formula is calculated, where the formula has an expression: [ P ] = (c 1A + c2 Uh) Ra. In the formula [ P ] represents the maximum bearing capacity of the pile foundation, Ra represents the ultimate compressive strength of the rock at the bottom of the pile foundation, h represents the depth of the pile foundation penetrating into the rock at the bottom, U represents the perimeter of the ground surface of the part of the pile foundation penetrating into the rock layer, A represents the cross-sectional area of the foundation, and the other c1 and c2 represent a relatively fixed coefficient.
Preferably, when the reinforcement of the pile foundation is determined, the load is combined according to the standard.
Preferably, during the manufacturing of the pile, isolation layers are manufactured between the upper-layer pile and the lower-layer pile, between the adjacent piles and between the pile and the bottom formwork, and concrete pouring of the upper-layer pile and the adjacent pile is performed when concrete of the lower-layer pile and the adjacent pile reaches more than 40% of the designed strength grade. The steel reinforcement frameworks of the reinforced concrete precast piles are preferably connected by welding, and the number of main reinforcement joints arranged in the same section (which means in a region of 30 times the diameter of the steel reinforcement but not less than 500 mm) is not more than 50 percent; the diameter of the steel bar between two adjacent joints of the same steel bar is more than 30 times and is not less than 500 mm; the upper part of the pile top main reinforcement is preferably extended to the lower part of the uppermost layer of the reinforcing mesh sheet, and the pile top main reinforcement is connected into an H shape.
Preferably, when the pile foundation is driven, the pile foundation must be driven slowly by selecting a short drop distance, and after the pile body enters the soil by about 2.5m, the pile foundation must be driven by using a full drop distance. When the drop hammer is used for striking, the drop distance is controlled within 1.3m, and the diesel hammer is controlled within 1.7 m.
Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages: the design method of the underground pile foundation building engineering provided by the invention is reasonable, simple and feasible, has strong practicability, can effectively improve the quality of the building engineering, reduce the cost of manpower and material resources, improve the construction efficiency and shorten the construction period, and the underground pile foundation designed by the design method has better stability, stronger stress resistance and bearing capacity and low possibility of deformation or instability; the surplus of the structural bearing capacity and the waste of materials are avoided, the construction cost is lower, and the quality is better.
Detailed Description
The invention relates to a design method of underground pile foundation building engineering, which comprises the following steps:
step S1, early design: designing according to the engineering construction project requirement, creating a WBS, and designing a safety guarantee system in the construction process of the underground pile foundation building engineering project, wherein the safety guarantee system comprises the integrity construction site guarantee safety and the construction process operation safety; designing construction quality and speed, and designing material, personnel and capital allocation;
step S2, foundation reconnaissance, foundation type selection: surveying the physical and mechanical performance parameters of foundation rock and soil, in-situ test parameters, underground water level conditions and seismic fortification intensity, determining the design grade of the foundation, the material of a pile foundation, the preliminary pile diameter and the plane of a distributed pile foundation according to JGJ 94-2008 'design Specification of building pile foundations';
step S3, pile size design: primarily estimating the section size, calculating the load of a pile foundation, determining the structural form of the pile foundation according to geological data and the load of the pile foundation, and reversely calculating the pile length and the pile bottom elevation according to rock-soil parameters and the load of the pile foundation so as to determine the pile bottom elevation; selecting a bearing stratum and determining the depth of a pile end entering the bearing stratum;
step S4, pile foundation calculation: calculating the bearing capacity of the pile foundation and determining the reinforcement of the pile foundation; determining the number, the spacing and the arrangement mode of the piles;
step S5, pile foundation design: looking up a map set through a calculation result and design requirements, and designing a pile body structure and a bearing platform of the pile body structure;
step S6, compiling a pile foundation calculation book, drawing a pile foundation plane layout, a pile foundation full-page design drawing, a drilling plane layout and a geological longitudinal section and pile bottom elevation design drawing;
and step S7, pile manufacturing, pile foundation driving and pile splicing.
In a preferred embodiment of the present invention, in step S2, the base design level is class c, and the pile foundation is made of PHC; the principle of selecting the bearing stratum and determining the depth of the pile end entering the bearing stratum is as follows: the depth of the full section of the pile end entering the bearing stratum is not less than 2d for cohesive soil and silty soil, not less than 1.5.5 d for sandy soil and not less than 1d for gravel soil. When a weak subjacent layer exists, the thickness of a hard bearing layer below the pile end is not smaller than 3d, wherein d is the embedding depth of the bearing platform. The burying depth of the bearing platform is not less than 700-800 mm. When the number of piles is determined in step S4, the number of piles is calculated according to the following formula: n is more than or equal to (Fk + Gk)/Ra (1.2-1.4) (considering bias), wherein Ra is the characteristic value of the estimated vertical bearing capacity of the single pile, Fk is the vertical force of a column root/a column top, and Gk is the dead weight of a bottom layer wall, a foundation beam, covering soil and a bearing platform.
The arrangement mode in the step S4 is to meet the requirement that the minimum center distance of the pile is more than or equal to 4d, the minimum width of the pile foundation bearing platform under the independent column is not less than 600mm, the distance from the center of the side pile to the edge of the bearing platform is not less than the diameter or the side length of the pile, and the distance from the outer edge of the pile to the edge of the bearing platform is not less than 200 mm. And designing the bearing platform reference pile foundation bearing platform atlas in the step S5. The structural form of the pile foundation is selected from one of an end-bearing pile and a friction pile.
In step S4, the pile foundation calculation formula for calculating the pile foundation bearing capacity is calculated, and the formula has the expression: [ P ] = (c 1A + c2 Uh) Ra. In the formula [ P ] represents the maximum bearing capacity of the pile foundation, Ra represents the ultimate compressive strength of the rock at the bottom of the pile foundation, h represents the depth of the pile foundation penetrating into the rock at the bottom, U represents the perimeter of the ground surface of the part of the pile foundation penetrating into the rock layer, A represents the cross-sectional area of the foundation, and the other c1 and c2 represent a relatively fixed coefficient. And when the reinforcement of the pile foundation is determined, the load is combined according to the standard.
During the manufacturing of the piles, isolation layers are manufactured between upper-layer piles and lower-layer piles, between adjacent piles and between the piles and the bottom formwork, and concrete pouring of the upper-layer piles and the adjacent piles is performed when concrete of the lower-layer piles and the adjacent piles reach over 40% of the designed strength grade. The steel reinforcement frameworks of the reinforced concrete precast piles are preferably connected by welding, and the number of main reinforcement joints arranged in the same section (which means in a region of 30 times the diameter of the steel reinforcement but not less than 500 mm) is not more than 50 percent; the diameter of the steel bar between two adjacent joints of the same steel bar is more than 30 times and is not less than 500 mm; the upper part of the pile top main reinforcement is preferably extended to the lower part of the uppermost layer of the reinforcing mesh sheet, and the pile top main reinforcement is connected into an H shape. When the pile foundation is driven, the pile foundation must be slowly driven by selecting a short drop distance, and after the pile body enters the soil by about 2.5m, the pile foundation is driven by using a full drop distance. When the drop hammer is used for striking, the drop distance is controlled within 1.3m, and the diesel hammer is controlled within 1.7 m. The design method of the underground pile foundation building engineering provided by the invention is reasonable, simple and feasible, has strong practicability, can effectively improve the quality of the building engineering, reduce the cost of manpower and material resources, improve the construction efficiency and shorten the construction period, and the underground pile foundation designed by the design method has better stability, stronger stress resistance and bearing capacity and low possibility of deformation or instability; the surplus of the structural bearing capacity and the waste of materials are avoided, the construction cost is lower, and the quality is better.
The following detailed description of preferred embodiments of the invention will be made.
Example 1
Embodiment 1 provides an underground pile foundation construction engineering design method, including the following steps:
step S1, early design: designing according to the engineering construction project requirement, creating a WBS, and designing a safety guarantee system in the construction process of the underground pile foundation building engineering project, wherein the safety guarantee system comprises the integrity construction site guarantee safety and the construction process operation safety; designing construction quality and speed, and designing material, personnel and capital allocation;
step S2, foundation reconnaissance, foundation type selection: surveying the physical and mechanical performance parameters of foundation rock and soil, in-situ test parameters, underground water level conditions and seismic fortification intensity, determining the design grade of the foundation, the material of a pile foundation, the preliminary pile diameter and the plane of a distributed pile foundation according to JGJ 94-2008 'design Specification of building pile foundations';
step S3, pile size design: primarily estimating the section size, calculating the load of a pile foundation, determining the structural form of the pile foundation according to geological data and the load of the pile foundation, and reversely calculating the pile length and the pile bottom elevation according to rock-soil parameters and the load of the pile foundation so as to determine the pile bottom elevation; selecting a bearing stratum and determining the depth of a pile end entering the bearing stratum;
step S4, pile foundation calculation: calculating the bearing capacity of the pile foundation and determining the reinforcement of the pile foundation; determining the number, the spacing and the arrangement mode of the piles;
step S5, pile foundation design: looking up a map set through a calculation result and design requirements, and designing a pile body structure and a bearing platform of the pile body structure;
and S6, compiling a pile foundation calculation book, drawing a pile foundation plane layout, a pile foundation full-page design drawing, a drilling plane layout and a geological longitudinal section and pile bottom elevation design drawing.
And step S7, pile manufacturing, pile foundation driving and pile splicing.
In the step S2, the basic design grade is grade C, and the material of the pile foundation is PHC;
the principle of selecting the bearing stratum and determining the depth of the pile end entering the bearing stratum is as follows: the depth of the full section of the pile end entering the bearing stratum is not less than 2d for cohesive soil and silty soil, not less than 1.5.5 d for sandy soil and not less than 1d for gravel soil. When a weak subjacent layer exists, the thickness of a hard bearing layer below the pile end is not smaller than 3d, wherein d is the embedding depth of the bearing platform.
The bearing platform is buried not less than 750 mm.
When the number of piles is determined in step S4, the number of piles is calculated according to the following formula: n is more than or equal to (Fk + Gk)/Ra (1.2-1.4) (considering bias), wherein Ra is the characteristic value of the estimated vertical bearing capacity of the single pile, Fk is the vertical force of a column root/a column top, and Gk is the dead weight of a bottom layer wall, a foundation beam, covering soil and a bearing platform.
The arrangement mode in the step S4 is to meet the requirement that the minimum center distance of the pile is more than or equal to 4d, the minimum width of the pile foundation bearing platform under the independent column is not less than 600mm, the distance from the center of the side pile to the edge of the bearing platform is not less than the diameter or the side length of the pile, and the distance from the outer edge of the pile to the edge of the bearing platform is not less than 200 mm.
And designing the bearing platform reference pile foundation bearing platform atlas in the step S5.
The structural form of the pile foundation is an end-bearing pile.
In step S4, the pile foundation calculation formula for calculating the pile foundation bearing capacity is calculated, and the formula has the expression: [ P ] = (c 1A + c2 Uh) Ra. In the formula [ P ] represents the maximum bearing capacity of the pile foundation, Ra represents the ultimate compressive strength of the rock at the bottom of the pile foundation, h represents the depth of the pile foundation penetrating into the rock at the bottom, U represents the perimeter of the ground surface of the part of the pile foundation penetrating into the rock layer, A represents the cross-sectional area of the foundation, and the other c1 and c2 represent a relatively fixed coefficient.
And when the reinforcement of the pile foundation is determined, the load is combined according to the standard.
During the manufacturing of the piles, isolation layers are manufactured between upper-layer piles and lower-layer piles, between adjacent piles and between the piles and the bottom formwork, and concrete pouring of the upper-layer piles and the adjacent piles is performed when concrete of the lower-layer piles and the adjacent piles reach over 40% of the designed strength grade. The steel reinforcement frameworks of the reinforced concrete precast piles are preferably connected by welding, and the number of main reinforcement joints arranged in the same section (which means in a region of 30 times the diameter of the steel reinforcement but not less than 500 mm) is not more than 50 percent; the diameter of the steel bar between two adjacent joints of the same steel bar is more than 30 times and is not less than 500 mm; the upper part of the pile top main reinforcement is preferably extended to the lower part of the uppermost layer of the reinforcing mesh sheet, and the pile top main reinforcement is connected into an H shape.
When the pile foundation is driven, the pile foundation must be slowly driven by selecting a short drop distance, and after the pile body enters the soil by about 2.5m, the pile foundation is driven by using a full drop distance. When the drop hammer is used for striking, the drop distance is controlled within 1.3m, and the diesel hammer is controlled within 1.7 m.
Example 2
Embodiment 2 provides a method for designing an underground pile foundation construction project, which is basically the same as embodiment 1, except that the pile foundation is in a friction pile structure.
The above embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims (10)

1. A design method for underground pile foundation building engineering is characterized by comprising the following steps:
step S1, early design: designing according to the engineering construction project requirement, creating a WBS, and designing a safety guarantee system in the construction process of the underground pile foundation building engineering project, wherein the safety guarantee system comprises the integrity construction site guarantee safety and the construction process operation safety; designing construction quality and speed, and designing material, personnel and capital allocation;
step S2, foundation reconnaissance, foundation type selection: surveying the physical and mechanical performance parameters of foundation rock and soil, in-situ test parameters, underground water level conditions and seismic fortification intensity, determining the design grade of the foundation, the material of a pile foundation, the preliminary pile diameter and the plane of a distributed pile foundation according to JGJ 94-2008 'design Specification of building pile foundations';
step S3, pile size design: primarily estimating the section size, calculating the load of a pile foundation, determining the structural form of the pile foundation according to geological data and the load of the pile foundation, and reversely calculating the pile length and the pile bottom elevation according to rock-soil parameters and the load of the pile foundation so as to determine the pile bottom elevation; selecting a bearing stratum and determining the depth of a pile end entering the bearing stratum;
step S4, pile foundation calculation: calculating the bearing capacity of the pile foundation and determining the reinforcement of the pile foundation; determining the number, the spacing and the arrangement mode of the piles;
step S5, pile foundation design: looking up a map set through a calculation result and design requirements, and designing a pile body structure and a bearing platform of the pile body structure;
step S6, compiling a pile foundation calculation book, drawing a pile foundation plane layout, a pile foundation full-page design drawing, a drilling plane layout and a geological longitudinal section and pile bottom elevation design drawing;
and step S7, pile manufacturing, pile foundation driving and pile splicing.
2. The method for designing an underground pile foundation construction project according to claim 1, wherein the foundation design grade in step S2 is grade c, and the pile foundation is made of PHC.
3. An underground pile foundation constructional engineering design method as claimed in claim 1 wherein the principle of selecting the bearing stratum and determining the depth of the pile end into the bearing stratum is: the depth of the full section of the pile end entering the bearing stratum is not less than 2d for cohesive soil and silty soil, not less than 1.5d for sandy soil and not less than 1d for broken stone soil; when a soft subjacent layer exists, the thickness of a hard bearing layer below the pile end is not suitable to be less than 3d, wherein d is the burying depth of the bearing platform; the burying depth of the bearing platform is not less than 700-800 mm.
4. An underground pile foundation construction engineering design method according to claim 1, wherein when the number of piles is determined in step S4, the number of piles is calculated according to the following formula: n is more than or equal to (Fk + Gk)/Ra (1.2-1.4) (considering bias), wherein Ra is the characteristic value of the estimated vertical bearing capacity of the single pile, Fk is the vertical force of a column root/a column top, and Gk is the dead weight of a bottom layer wall, a foundation beam, covering soil and a bearing platform.
5. The method for designing underground pile foundation constructional engineering according to claim 1, wherein the arrangement manner in step S4 is to satisfy that the minimum center distance of the piles is more than or equal to 4d, the minimum width of the pile foundation bearing platform under the independent column is not less than 600mm, the distance from the center of the side pile to the edge of the bearing platform is not less than the diameter or the side length of the pile, and the distance from the outer edge of the pile to the edge of the bearing platform is not less than 200 mm.
6. A method for designing underground pile foundation construction engineering according to claim 1, wherein the bearing platform is designed by referring to a pile foundation bearing platform atlas in step S5.
7. An underground pile foundation construction engineering design method according to claim 1, wherein the pile foundation is in a structural form selected from one of end-supported piles and friction piles.
8. A method for designing underground pile foundation constructional engineering according to claim 1, wherein the calculation formula for calculating the pile foundation bearing capacity of the pile foundation in step S4 is as follows: [ P ] = (c 1A + c2 Uh) Ra; in the formula [ P ] represents the maximum bearing capacity of the pile foundation, Ra represents the ultimate compressive strength of the rock at the bottom of the pile foundation, h represents the depth of the pile foundation penetrating into the rock at the bottom, U represents the perimeter of the ground surface of the part of the pile foundation penetrating into the rock layer, A represents the cross-sectional area of the foundation, and the other c1 and c2 represent a relatively fixed coefficient.
9. The method for designing underground pile foundation construction engineering according to claim 1, wherein during the pile manufacturing, isolation layers are prepared between the upper and lower piles, between the adjacent piles and between the piles and the bottom formwork, and concrete pouring of the upper pile and the adjacent pile is performed when concrete of the lower pile and the adjacent pile reaches more than 40% of the designed strength grade; the steel reinforcement frameworks of the reinforced concrete precast piles are preferably connected by welding, and the number of main reinforcement joints arranged in the same section (which means in a region of 30 times the diameter of the steel reinforcement but not less than 500 mm) is not more than 50 percent; the diameter of the steel bar between two adjacent joints of the same steel bar is more than 30 times and is not less than 500 mm; the upper part of the pile top main reinforcement is preferably extended to the lower part of the uppermost layer of the reinforcing mesh sheet, and the pile top main reinforcement is connected into an H shape.
10. The method for designing underground pile foundation constructional engineering according to claim 1, wherein when the pile foundation is driven in, the pile foundation must be driven slowly by selecting a short drop distance, and after the pile body enters the soil for about 2.5m, the pile foundation must be driven by using a full drop distance; when the drop hammer is used for striking, the drop distance is controlled within 1.3m, and the diesel hammer is controlled within 1.7 m.
CN201911231376.2A 2019-05-13 2019-12-05 Underground pile foundation construction engineering design method Withdrawn CN110889235A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113378275A (en) * 2021-06-18 2021-09-10 福建工程学院 Method for predicting pile driving force of end of precast pile when encountering boulder

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113378275A (en) * 2021-06-18 2021-09-10 福建工程学院 Method for predicting pile driving force of end of precast pile when encountering boulder
CN113378275B (en) * 2021-06-18 2022-06-21 福建工程学院 Method for predicting piling force of precast pile end in case of boulder

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Application publication date: 20200317