CN104032732A - Cast-in-place type prestress steel plate concrete pile, construction method thereof and support pile wall - Google Patents

Abstract

The invention discloses a cast-in-place type prestress steel plate concrete pile, a construction method thereof and a support pile wall. The cast-in-place type prestress steel plate concrete pile comprises a hollow outer shell which is made of steel plates, concrete which is formed in the hollow outer shell in a cast-in-place mode, and a plurality of prestressed tendons which are arranged in the concrete. The upper end of the hollow outer shell is opened, and the bottom end of the hollow outer shell is of a closed structure. The construction method of the cast-in-place type prestress steel plate concrete pile and the support pile wall which is provided with the cast-in-place type prestress steel plate concrete pile are further included. By the adoption of the mode, the cast-in-place type prestress steel plate concrete pile can be fabricated on site according to design requirements, the disadvantages caused by pile body spreading and transporting are avoided, transportation cost is saved, on the premise that the safety and reliability of a foundation pit support are guaranteed, engineering cost can be lowered, and construction is convenient.

Description

Cast-in-place prestressed steel sheet concrete pile and its construction method and supporting pile wall

technical field

The invention relates to all construction engineering fields such as construction, municipal administration, transportation, water conservancy, electric power, industry, etc., and particularly relates to a cast-in-place prestressed steel plate concrete pile, a construction method thereof and a supporting pile wall.

Background technique

The technical scheme of foundation pit engineering is mainly considered from the aspects of safety reliability, economic rationality, construction difficulty and construction period. There are many applications of SMW construction method piles, cast-in-place piles and underground diaphragm walls in soft soil areas around the coast of my country.

The steel-cement-soil mixing wall, commonly referred to as the SMW construction method, is a composite soil-retaining and water-proof structure formed by inserting section steel into continuously socketed three-axis cement-soil mixing piles. That is to use the three-axis mixing pile drilling rig to cut the soil in the original formation, and at the same time inject the cement slurry at low pressure in the front section of the drilling rig, and fully mix with the chopped soil to form a cement-soil pile column retaining wall with high water resistance, and insert it before the cement-soil slurry has hardened. An underground engineering construction technology of section steel. The SMW construction method pile is developed based on the deep mixing pile construction technology. This structure gives full play to the mechanical properties of the cement-soil mixture and section steel, and has the characteristics of economy, short construction period, strong water resistance, and small impact on the surrounding environment. After the maintenance structure of the steel cement-soil mixing wall is completed in the basement, the H-shaped steel can be pulled out from the cement-soil mixing pile to achieve the purpose of recycling and reuse. Therefore, compared with conventional maintenance methods, this construction method not only has a shorter construction period, no pollution during the construction process, a clean site, and low noise, but also saves social resources and prevents the maintenance body from permanently remaining underground after construction in the basement and becoming an underground obstacle. Today, when advocating the construction of a conservation-oriented society and realizing sustainable development, it is more practical to popularize and apply this construction method.

However, SMW construction method piles have the following disadvantages: H-shaped steel is mostly used in SMW construction method piles, and the cost of H-shaped steel is high. In the actual construction process, the transportation cost and leasing cost of the section steel are very high, especially when the construction period is long. , The rental cost of section steel will greatly increase the cost of use. In addition, the section steel generally needs to be pulled out after the construction of the basement is completed, which may lead to losses such as bending and breaking of the section steel, and will greatly increase the project cost when the site limit cannot be pulled out.

Cast-in-situ piles use a lot of steel bars and concrete, and additional water-stop curtains need to be installed. The construction is cumbersome and has a relatively large impact on the environment.

Therefore, the supporting structure used in the existing building foundation pit engineering can not fully meet the engineering requirements, and it is necessary to develop a new type of foundation pit supporting structure, which is safe, reliable, economical and reasonable, and convenient for construction.

Contents of the invention

The technical problem mainly solved by the present invention is to provide a cast-in-place prestressed steel sheet concrete pile and its construction method and supporting pile wall. Disadvantages caused by lengthening and transportation save transportation costs. On the premise of ensuring the safety and reliability of foundation pit support, it can reduce engineering costs and facilitate construction.

In order to solve the above technical problems, a technical solution adopted by the present invention is to provide a cast-in-place prestressed steel sheet concrete pile, comprising: a hollow outer shell composed of steel plates, and concrete cast-in-place inside the hollow outer shell layer and a plurality of prestressed tendons arranged in the concrete layer, the upper end of the hollow outer casing is open, and the bottom end is a closed structure.

In a preferred embodiment of the present invention, the hollow outer shell has a dumbbell-shaped cross section, including an upper flange, a lower flange and a web disposed between the upper flange and the lower flange.

In a preferred embodiment of the present invention, the upper flange, the lower flange and the web are all rectangular, the upper flange is arranged parallel to the lower flange, and the web is arranged perpendicular to the upper flange.

In a preferred embodiment of the present invention, the upper flange and the lower flange are rectangular, and the web includes two symmetrically arranged concave arc-shaped steel plates.

In a preferred embodiment of the present invention, the prestressed tendons are arranged in the upper flange and the lower flange, and the prestressed tendons in the upper flange and the prestressed tendons in the lower flange are arranged symmetrically.

In a preferred embodiment of the present invention, the prestressed tendon includes a bonded section tightly bonded to concrete and an unbonded section exposed to concrete.

In a preferred embodiment of the present invention, the bottom end of the hollow outer casing is a pyramid-shaped closed structure.

The present invention also provides a construction method for the above-mentioned cast-in-place prestressed steel sheet concrete pile, comprising the following specific steps:

a. A formwork is arranged inside the hollow outer shell, and there are a plurality of conduits matching the positions of the prestressing tendons in the formwork;

b. Use cement-soil mixing pile construction machinery for construction to form cement-soil mixing piles;

c. Put the hollow outer casing and formwork into the cement-soil mixing pile, and put prestressed tendons in each conduit;

d. Concrete is poured from the opening of the upper end of the hollow outer shell to its interior. The formwork and conduits are lifted up during the concrete pouring process. When the concrete pouring is completed, the formwork and conduits are also completely pulled out.

In a preferred embodiment of the present invention, in step d, the template and the conduit are lifted upwards by a vibrating machine.

The present invention also provides a support pile wall with the above-mentioned cast-in-place prestressed steel sheet concrete piles, the support pile wall includes several cement-soil mixing piles and cast-in-place concrete piles arranged in the cement-soil mixing piles Prestressed steel sheet concrete piles.

The present invention has the following beneficial effects:

1. The cast-in-place prestressed steel sheet concrete pile of the present invention can be poured on-site in the cement-soil mixing pile according to the design requirements, which avoids the trouble of lengthening the pile body and reduces the transportation cost.

2. Compared with bored cast-in-place piles, the cast-in-place prestressed steel sheet concrete piles of the present invention use less steel bars and concrete, save costs, and have little impact on the environment.

3. Compared with the SMW construction method pile, the cast-in-place prestressed steel sheet concrete pile of the present invention has increased strength relative to the section steel, reduced transportation costs, and does not need to be pulled out, which avoids the problem of removal loss of the section steel after the completion of the project.

4. The supporting pile wall of the present invention adopts cast-in-place prestressed steel sheet concrete piles, which have better bending stiffness and high supporting strength.

In summary, the cast-in-place prestressed steel sheet concrete pile and its construction method and supporting pile wall of the present invention not only ensure the safety and reliability of the foundation pit supporting structure, but also have good economic benefits, are convenient for construction, and have little environmental impact. Further meet the needs of foundation pit engineering construction.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative work, wherein:

Fig. 1 is the cross-sectional structural schematic diagram one of described cast-in-place prestressed steel sheet concrete pile;

Fig. 2 is the cross-section schematic diagram II of the cast-in-place prestressed steel sheet concrete pile;

Fig. 3 is the cross-section schematic diagram three of the cast-in-place prestressed steel sheet concrete pile;

Fig. 4 is the structural representation of a preferred embodiment of the present invention's supporting pile wall;

Fig. 5 is a structural schematic diagram of another preferred embodiment of the present invention supporting pile walls.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Please refer to Fig. 1 to Fig. 5, the embodiment of the present invention comprises:

Embodiment one:

Referring to Fig. 1 and Fig. 4, a kind of cast-in-place prestressed steel sheet concrete pile comprises: a hollow outer shell 11 made of steel plates, a concrete layer 12 cast in place inside the hollow outer shell 11 and arranged on the A plurality of prestressed tendons 13 in the concrete layer 12, the upper end of the hollow outer shell 11 is open, and the bottom end is a closed structure. The cast-in-place prestressed steel sheet concrete pile is made by pouring in situ, which reduces transportation costs. Construction is convenient.

The wall thickness of the steel plate forming the hollow outer shell 11 is 1.5mm~30mm, which is set according to different construction projects.

The hollow outer shell 11 has a dumbbell-shaped section, including an upper flange 111, a lower flange 112, and a web 113 arranged between the upper flange 111 and the lower flange 112. The structure is reasonable, and after pouring concrete higher strength can be obtained.

The upper flange 111 , the lower flange 112 and the web 113 are all rectangular, the upper flange 111 is arranged parallel to the lower flange 112 , and the web 113 is arranged vertically to the upper flange 111 .

The prestressed tendons 13 are arranged in the upper flange 111 and the lower flange 112, and the prestressed tendons in the upper flange and the prestressed tendons in the lower flange are arranged symmetrically.

The prestressed tendon 13 includes a bonded section closely bonded to the concrete and an unbonded section exposed to the concrete, the bonded section is tightly bonded to the concrete, and the unbonded section is used to achieve the pre-stressing effect on the pile body. Prestress is applied after stress intensity.

As shown in Figure 4, the present invention also provides a support pile wall with the above-mentioned cast-in-place prestressed steel sheet concrete pile, and the support pile wall includes several cement-soil mixing piles and is arranged on the cement-soil mixing pile. Cast-in-place prestressed steel sheet concrete piles inside piles.

The cement-soil mixing pile is constructed with a three-axis cement-soil mixing pile construction machine, and three interlocking cement-soil mixing piles are processed each time, which are the front pile, the middle pile and the rear pile, forming a cement-soil mixing pile unit The wall is formed by various construction methods, and cast-in-place prestressed steel plate concrete piles are arranged continuously or at intervals in the cement-soil mixing piles.

The supporting pile wall is composed of a plurality of cement-soil mixing pile units arranged in dislocation, the rear pile of the former cement-soil mixing pile unit and the front pile of the latter cement-soil mixing pile unit interlock to form a staggered structure, which enhances the Overall bending stiffness and lateral movement resistance. In the actual construction process, small-sized cast-in-place prestressed steel plate concrete piles can be set in the separate cement-soil mixing piles, and large-size cast-in-place prestressed steel plate can be set in the interlocking cement-soil mixing piles at the dislocation Concrete piles.

Embodiment two:

Referring to Fig. 2 and Fig. 5, a kind of cast-in-place prestressed steel sheet concrete pile comprises: a hollow outer shell 21 made of steel plates, a concrete layer 22 cast in place inside the hollow outer shell 21 and arranged on the A plurality of prestressed tendons 23 in the concrete layer 22, the upper end of the hollow outer shell 21 is open, and the bottom end is a closed structure. The cast-in-place prestressed steel sheet concrete pile is made by pouring in situ, which reduces transportation costs. Construction is convenient.

The section of the hollow outer shell 21 is dumbbell-shaped, including an upper flange 211, a lower flange 212 and a web 213 arranged between the upper flange 211 and the lower flange 212. The structure is reasonable, and after pouring concrete higher strength can be obtained.

The upper flange 211 and the lower flange 212 are rectangular, and the web 213 includes two symmetrically arranged concave arc-shaped steel plates 214 .

The prestressed tendons 23 are arranged in the upper flange 211 and the lower flange 212, and the prestressed tendons in the upper flange and the prestressed tendons in the lower flange are arranged symmetrically.

The prestressed tendon 23 includes a bonded section closely bonded to the concrete and an unbonded section exposed to the concrete, the bonded section is closely bonded to the concrete, and the unbonded section is used to achieve the pre-stressing effect on the pile body. Prestress is applied after stress intensity.

As shown in Figure 5, the present invention also provides a support pile wall with the above-mentioned cast-in-place prestressed steel sheet concrete pile, and the support pile wall includes several cement-soil mixing piles and is arranged on the cement-soil mixing pile. Cast-in-place prestressed steel sheet concrete piles inside piles.

The cement-soil mixing pile is constructed with a three-axis cement-soil mixing pile construction machine, and three interlocking cement-soil mixing piles are processed each time, which are the front pile, the middle pile and the rear pile, forming a cement-soil mixing pile unit The wall is formed by various construction methods, and cast-in-place prestressed steel plate concrete piles are arranged continuously or at intervals in the cement-soil mixing piles.

The supporting pile wall includes a cement-soil wall matrix composed of a plurality of cement-soil mixing piles arranged in sequence and interlocking with each other, and a plurality of cement-soil wall matrixes parallel to the cement-soil wall matrix are arranged at intervals on one side of the cement-soil wall matrix. Soil mixing pile unit, the interval distance can be a cement-soil mixing pile or a plurality of cement-soil mixing piles, depending on the length of the actual cement-soil wall matrix, the three piles of the cement-soil mixing pile unit are respectively connected to the cement-soil mixing pile. The three piles on the base of the wall interlock to form a convex structure, and the cement-soil mixing piles are provided with cast-in-place prestressed steel sheet concrete piles continuously or at intervals, which enhances the overall bending stiffness and lateral movement resistance. In the actual construction process, small-sized cast-in-place prestressed steel sheet concrete piles can be installed in separate cement-soil mixing piles, and large-scale cast-in-place prestressed steel sheet concrete piles can be installed in interlocking cement-soil mixing piles at the convex structure. Stressed steel sheet concrete piles.

Embodiment three:

As shown in FIG. 3 , the third embodiment of the present invention is basically the same as the first embodiment, the main difference is that the two sides of the upper flange and the lower flange are changed from straight sides to arc sides.

The present invention also provides a construction method for the above-mentioned cast-in-place prestressed steel sheet concrete pile, comprising the following specific steps:

a. A formwork is arranged inside the hollow outer shell, and there are a plurality of conduits matching the positions of the prestressing tendons in the formwork;

b. Use cement-soil mixing pile construction machinery for construction to form cement-soil mixing piles;

c. Put the hollow outer casing and formwork into the cement-soil mixing pile, and put prestressed tendons in each conduit respectively. The bottom end of the hollow outer casing is a pyramid-shaped closed structure, which avoids the insertion of the hollow outer casing During the process, the cement slurry in the cement soil enters the hollow shell and affects the strength of the high-strength concrete;

The bottom end of the hollow outer shell is a pyramid-shaped closed structure, which also makes the process of putting the hollow outer shell into the cement-soil mixing pile smoother;

d. Concrete is poured from the upper opening of the hollow outer shell to its interior. The formwork and conduits are lifted upward during the concrete pouring process. When the concrete pouring is completed, the formwork and conduits are also completely pulled out, and the formwork and conduits are lifted upwards by a vibrating machine. While lifting, the concrete is compacted by the vibration and vibration of the formwork.

The present invention has the following beneficial effects:

1. The cast-in-place prestressed steel sheet concrete pile of the present invention can be poured on-site in the cement-soil mixing pile according to the design requirements, which avoids the trouble of lengthening the pile body and reduces the transportation cost.

2. Compared with bored cast-in-place piles, the cast-in-place prestressed steel sheet concrete piles of the present invention use less steel bars and concrete, save costs, and have little impact on the environment.

3. Compared with the SMW construction method pile, the cast-in-place prestressed steel sheet concrete pile of the present invention has increased strength relative to the section steel, reduced transportation costs, and does not need to be pulled out, which avoids the problem of removal loss of the section steel after the completion of the project.

4. The supporting pile wall of the present invention adopts cast-in-place prestressed steel sheet concrete piles, which have better bending stiffness and high supporting strength.

In summary, the cast-in-place prestressed steel sheet concrete pile and its construction method and supporting pile wall of the present invention not only ensure the safety and reliability of the foundation pit supporting structure, but also have good economic benefits, are convenient for construction, and have little environmental impact. Further meet the needs of foundation pit engineering construction.

The above descriptions are only examples of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the content of the description of the present invention, or directly or indirectly used in other related technical fields, shall be The same reasoning is included in the patent protection scope of the present invention.

Claims (10)

1. a cast-in-place prestressed steel sheet concrete pile, is characterized in that, comprises: the hollow outer shell that is made up of steel plate, the concrete layer that forms in-situ cast in described hollow outer shell inside and be arranged in the concrete layer A plurality of prestressed tendons, the upper end of the hollow outer casing is open, and the bottom end is a closed structure. 2. The cast-in-place prestressed steel sheet concrete pile according to claim 1, characterized in that, the section of the hollow outer shell is dumbbell-shaped, including an upper flange, a lower flange, and an upper flange, The web between the lower flanges. 3. The cast-in-place prestressed steel sheet concrete pile according to claim 2, wherein the upper flange, the lower flange and the web are all rectangular, and the upper flange and the lower flange are arranged in parallel, The web is arranged vertically to the upper flange. 4. The cast-in-place prestressed steel sheet concrete pile according to claim 2, wherein the upper flange and the lower flange are rectangular, and the web comprises two symmetrically arranged concave arc-shaped steel plates . 5. The cast-in-place prestressed steel sheet concrete pile according to claim 2, wherein the prestressed tendons are arranged in the upper flange and the lower flange, and the prestressed tendons in the upper flange and the lower flange The prestressed tendons in the edge are arranged symmetrically. 6. The cast-in-place prestressed steel sheet concrete pile according to claim 1, characterized in that, the prestressed tendon includes a bonded section tightly bonded to concrete and an unbonded section exposed to concrete. 7. The cast-in-place prestressed steel sheet concrete pile according to claim 1, characterized in that, the bottom end of the hollow shell is a pyramid-shaped closed structure. 8. A construction method of the cast-in-place prestressed steel sheet concrete pile as claimed in claim 1, is characterized in that, comprises the following concrete steps: a. A formwork is arranged inside the hollow outer shell, and there are a plurality of conduits matching the positions of the prestressing tendons in the formwork; b. Use cement-soil mixing pile construction machinery for construction to form cement-soil mixing piles; c. Put the hollow outer casing and formwork into the cement-soil mixing pile, and put prestressed tendons in each conduit; d. Concrete is poured from the opening of the upper end of the hollow outer shell to its interior. The formwork and conduits are lifted up during the concrete pouring process. When the concrete pouring is completed, the formwork and conduits are also completely pulled out. 9. The construction method of the cast-in-place prestressed steel sheet concrete pile according to claim 8, characterized in that, in step d, the template and the conduit are lifted upwards by a vibrating machine. 10. A supporting pile wall, characterized in that, the supporting pile wall comprises several cement-soil mixing piles and cast-in-place prestressed steel sheet concrete piles arranged in the cement-soil mixing piles, the cast-in-place The prestressed steel sheet concrete pile is the cast-in-place prestressed steel sheet concrete pile described in any one of claims 1 to 7.