Low-disturbance three-dimensional frame foundation pit supporting structure and supporting method thereof

Abstract

The invention discloses a low-disturbance three-dimensional frame foundation pit supporting structure and a supporting method thereof.The supporting structure comprises two circles of row piles used for being arranged on the periphery of the design position of a foundation pit in a surrounding mode, and each circle of row piles is formed by arranging a plurality of micro piles; each micro pile comprises a steel core body and a cement mortar body which is wrapped and fixed outside the steel core body; the top beam is used for being connected to the tops of the two circles of row piles in series, and the top of the steel core body of each micro pile is anchored in the top beam; the multiple cable-stayed piles are arranged in the circumferential direction of the top beam at intervals, the first end of each cable-stayed pile is anchored in the top beam, the second end of each cable-stayed pile is obliquely inserted in the soil body on the outer sides of the two circles of row piles, and by arranging the supporting structure, the influence of soil body disturbance on the surrounding environment is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of building construction, and in particular to a low-disturbance three-dimensional frame foundation pit supporting structure and a supporting method thereof. Background Art

[0002] Existing foundation pit supports are mostly concrete cast-in-place piles, ground-anchored walls, precast piles, etc. These traditional construction processes are relatively complex and have a long construction period. At the same time, when there are existing roads and existing buildings around the foundation pit, the above-mentioned foundation pit support methods have a large disturbance on the soil, which will cause damage to the existing roads and existing buildings and is not conducive to the high-quality development of the enterprise. Summary of the invention

[0003] The purpose of the present invention is to overcome the defects of the prior art and provide a low-disturbance three-dimensional frame foundation pit support structure and a support method thereof. The construction process is simple, the construction cost is low, the construction period is short, and the disturbance to the surrounding environment is small. By constructing double rows of micro piles and crown beams, a frame support system is formed, and a simple vertical truss space system structure is formed, which fully utilizes the axial force of the micro piles, improves the support capacity, and ensures the safety of the support structure.

[0004] To achieve the above purpose, the technical solution adopted by the present invention is a low-disturbance three-dimensional frame foundation pit support structure, comprising:

[0005] Two circles of piles are arranged around the periphery of the designed position of the foundation pit, each circle of piles is composed of a plurality of micro piles arranged in an arranged manner, and each of the micro piles comprises a steel core body and a cement mortar body wrapped and fixed outside the steel core body;

[0006] A crown beam connected in series to the top of two circles of piles, wherein the top of the steel core of each micropile is anchored in the crown beam;

[0007] A plurality of inclined piles are arranged at intervals along the circumference of the crown beam, wherein the first end of each inclined pile is anchored in the crown beam, and the second end is obliquely inserted into the soil outside the two circles of pile rows.

[0008] A further improvement of the low-disturbance stereo frame foundation pit support structure of the present invention is that the micro-piles in the two circles of pile rows are arranged in a plum blossom shape.

[0009] A further improvement of the low-disturbance stereo frame foundation pit support structure of the present invention is that the foundation pit support structure also includes a wire mesh hung on the inner side of two circles of piles and a concrete face sprayed on the wire mesh.

[0010] A low-disturbance three-dimensional frame foundation pit support method, comprising the steps of:

[0011] Step 1: construct two circles of piles on the periphery of the designed location of the foundation pit, each circle of piles is composed of a plurality of micro piles arranged in an arranged manner, and each of the micro piles includes a steel core body and a cement mortar body wrapped and fixed outside the steel core body;

[0012] Step 2: construct multiple inclined piles at intervals on the periphery of the designed position of the foundation pit, so that the first end of each inclined pile is flush with the top of the two circles of piles, and the second end is obliquely inserted into the soil outside the two circles of piles;

[0013] Step 3: Cast the cap beam and anchor the top ends of the two circles of piles and the first ends of multiple cable-stayed piles.

[0014] A further improvement of the low-disturbance stereo frame foundation pit support structure of the present invention is that, when executing the above step 2, a high wind pressure casing is first used to drill a hole at the designed position of each micropile, and a steel core is inserted into the corresponding hole, and then a cement mortar body is poured in the hole to form the micropile.

[0015] Compared with the prior art, the advantages of the present invention are:

[0016] The construction process is simple, the construction cost is low, the construction period is short, and the disturbance to the surrounding environment is small. By constructing double-circle micro-piles and crown beams, a frame support system is formed, forming a simple vertical truss space system structure, which fully exerts the axial force of the micro-pile, improves the support capacity, and ensures the safety of the support structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0018] Figure 1 It is a schematic diagram of the use status of the low-disturbance three-dimensional frame foundation pit supporting structure of the present invention.

[0019] Figure 2 It is a schematic diagram of the distribution of two rows of micro piles and multiple inclined-stayed piles of the low-disturbance three-dimensional frame foundation pit support structure of the present invention.

[0020] Figure 3 It is a schematic diagram of the internal structure of the micro pile of the low-disturbance three-dimensional frame foundation pit support structure of the present invention.

[0021] In the figure: 1. micro pile; 101. steel core; 102. steel bar; 2. cap beam; 3. inclined-stayed pile; 4. hook. DETAILED DESCRIPTION

[0022] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0023] The low-disturbance stereo frame foundation pit support structure and support method thereof of the present invention are further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0024] See also Figure 1 to Figure 3 As shown, the low-disturbance stereo frame foundation pit support structure includes:

[0025] Two circles of piles are arranged around the periphery of the designed position of the foundation pit, each circle of piles is composed of a plurality of micro piles 1 arranged in an arranged manner, and each of the micro piles 1 includes a steel core 101 and a cement mortar body wrapped and fixed outside the steel core 101;

[0026] A crown beam 2 connected in series to the top of two circles of piles, the top of the steel core 101 of each micropile 1 is anchored in the crown beam 2;

[0027] A plurality of inclined piles 3 are arranged at intervals along the circumferential direction of the crown beam 2. The first end of each inclined pile 3 is anchored in the crown beam 2, and the second end is obliquely inserted into the soil outside the two circles of piles.

[0028] By providing the cap beam 2, two circles of piles and a plurality of the inclined piles 3 are connected in series to form an overall frame structure, thereby improving the integrity and the enclosure effect.

[0029] Specifically, the inclined-stayed pile 3 , like the micro pile 1 , is also composed of a steel core 101 and a cement mortar body wrapped and fixed to the outside of the steel core 101 .

[0030] Specifically, the steel core 101 is an I-beam, and a steel bar 102 is welded throughout the connection node between the web plate of the steel core 101 and the two flange plates.

[0031] By further welding the steel bars 102 to the steel core 101 , the pile strength of the micropile 1 is improved.

[0032] Preferably, the micro piles 1 in the two circles of piles are arranged in a plum blossom shape.

[0033] By arranging the micro-piles 1 in the two circles of pile rows in a plum blossom shape, the soil disturbances when drilling the micro-piles 1 in the two circles of pile rows are avoided from affecting each other.

[0034] Specifically, Figure 2As shown: the micro-piles 1 in the two circles of piles are arranged in a plum blossom shape. Obviously, the multiple micro-piles 1 in each circle are arranged at intervals, and the first ends of the multiple inclined piles 3 are interspersed with the multiple micro-piles 1 in the outer circle of piles.

[0035] Preferably, the foundation pit supporting structure also includes a wire mesh hung on the inner side of the two circles of piles and a concrete face sprayed on the wire mesh.

[0036] Specifically, hooks 4 for hanging the wire mesh are connected at intervals on the inner sides of the two circles of piles.

[0037] By setting the wire mesh and spraying the concrete face, the multiple micropiles 1 in the inner circle pile row are completely covered, preventing soil from entering the foundation pit through the gaps between the multiple micropiles 1 in the inner circle pile row, thereby improving the protection effect of the foundation pit.

[0038] A low-disturbance three-dimensional frame foundation pit support method, comprising the steps of:

[0039] Step 1: construct two circles of piles on the periphery of the designed position of the foundation pit, each circle of piles is composed of a plurality of micro piles 1 arranged in an arranged manner, and each of the micro piles 1 includes a steel core 101 and a cement mortar body wrapped and fixed outside the steel core 101;

[0040] Step 2: construct multiple inclined piles 3 at intervals on the periphery of the designed position of the foundation pit, so that the first end of each inclined pile 3 is flush with the top of the two circles of piles, and the second end is obliquely inserted into the soil outside the two circles of piles;

[0041] Step 3: Cast the cap beam 2, and anchor the top ends of the two circles of piles and the first ends of the plurality of inclined piles 3 therein.

[0042] Preferably, when executing the above step 2, a high wind pressure casing is first used to drill a hole at the designed position of each micropile 1, and the steel core 101 is inserted into the corresponding hole, and then cement mortar is poured in the hole to form the micropile 1.

[0043] By adopting high-pressure casing and pipe DTH drilling, the disturbance of soil caused by drilling is further reduced, thus improving the construction stability.

[0044] Specifically, when drilling at the designed position of each micropile 1, the drilling depth is made less than the length of the corresponding steel core 101, and the drilling depth satisfies: when the steel core 101 is inserted into the corresponding hole, the top of the steel core 101 is exposed and the top elevation is flush with the top design elevation of the crown beam 2.

[0045] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change of the proportion relationship or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. The change or adjustment of their relative relationship should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0046] The above is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as a preferred embodiment as above, it is not used to limit the present invention. Any technician familiar with this profession can make some changes or modifications to equivalent embodiments of equivalent changes using the technical contents disclosed above without departing from the scope of the technical solution of the present invention. However, any simple modification, equivalent change and modification made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A low-disturbance three-dimensional frame foundation pit support structure, characterized in that: include: Two circles of piles are arranged around the periphery of the designed position of the foundation pit, each circle of piles is composed of a plurality of micro piles arranged in an arranged manner, and each of the micro piles comprises a steel core body and a cement mortar body wrapped and fixed outside the steel core body; A crown beam connected in series to the top of two circles of piles, wherein the top of the steel core of each micropile is anchored in the crown beam; A plurality of inclined piles are arranged at intervals along the circumference of the crown beam, wherein the first end of each inclined pile is anchored in the crown beam, and the second end is obliquely inserted into the soil outside the two circles of pile rows.

2. The low-disturbance three-dimensional frame foundation pit support structure according to claim 1, characterized in that: The micro piles in the two circles of pile rows are arranged in a plum blossom shape.

3. The low-disturbance three-dimensional frame foundation pit support structure according to claim 1, characterized in that: The foundation pit supporting structure also includes a wire mesh hung on the inner sides of two circles of piles and a concrete face sprayed on the wire mesh.

4. A low-disturbance three-dimensional frame foundation pit support method, characterized in that: Includes steps: Step 1: construct two circles of piles on the periphery of the designed location of the foundation pit, each circle of piles is composed of a plurality of micro piles arranged in an arranged manner, and each of the micro piles includes a steel core body and a cement mortar body wrapped and fixed outside the steel core body; Step 2: construct multiple inclined piles at intervals on the periphery of the designed position of the foundation pit, so that the first end of each inclined pile is flush with the top of the two circles of piles, and the second end is obliquely inserted into the soil outside the two circles of piles; Step 3: Cast the cap beam and anchor the top ends of the two circles of piles and the first ends of multiple cable-stayed piles.

5. The low-disturbance three-dimensional frame foundation pit support method according to claim 4, characterized in that: When executing the above step 2, a high wind pressure casing is first used to drill a hole at the designed position of each micropile, and a steel core is inserted into the corresponding hole, and then cement mortar is poured in the hole to form the micropile.

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