CN207079596U - A kind of board-like double-row pile foundation pit support structure of counterfort - Google Patents

Abstract

The utility model discloses a buttress plate type double-row pile foundation pit support structure, which comprises a front row of support piles and a rear row of support piles arranged at intervals along the direction of the side wall of the foundation pit, and a front row of support piles and a rear row of piles. The pile tops of the supporting piles all have crown beams, the pile top elevation of the front row of supporting piles is lower than that of the rear row of supporting piles, and there is a continuous pile top between the front row of supporting piles and the rear row of supporting piles. The supporting boards are connected, and buttress boards are arranged at intervals along the direction of the side wall of the foundation pit between the pile top supporting board and the rear supporting piles, and water-stop piles are arranged behind the rear supporting piles. By lowering the front supporting piles, The pile top elevation not only gives full play to the bending resistance of the rear support piles, but also reduces the 1-2 internal supports at the top of the foundation pit, speeding up the construction progress of the foundation pit; moreover, the front support piles and the rear support piles The protection piles are connected by the pile top support plate and the buttress plate, which can transmit the horizontal force of the rear support piles to the front support piles, and improve the integrity and overall rigidity of the entire support structure.

Description

A buttress plate type double-row pile foundation pit support structure

technical field

The utility model relates to the technical field of foundation pit support structures, in particular to a foundation pit support structure with double rows of piles.

Background technique

The utilization of underground space plays an important role in improving the ground environment. While developing underground transportation and reducing urban air pollution, the construction of urban underground comprehensive utility corridors should also be advocated. Underground space can be developed into underground railways, underground stations, underground roads, underground parking garages, underground shopping malls, underground civil defense projects, etc. The excavation of underground spaces is inseparable from foundation pit support structures. The foundation pit support structure is to ensure the safety of the underground structure construction and the surrounding environment of the foundation pit, and the support, reinforcement and protection measures are adopted for the side wall of the foundation pit and the surrounding environment.

The double-row pile foundation pit support structure is more and more widely used. The foundation pit support structure is a space portal structure system formed by two parallel rows of reinforced concrete piles and the connecting beam on the top of the pile. Due to the common double-row The pile foundation pit support structure has the advantages of high overall rigidity, simple and fast construction, etc., and is suitable for use when the excavation depth of the foundation pit is not large. When the excavation depth of the foundation pit is large or the geological conditions are poor, or in some special cases, the general double-row pile foundation pit support structure cannot meet the design requirements. How to meet the requirements of maintaining the support structure Stability and convenient construction are the biggest problems encountered by ordinary double-row pile support structures. Therefore, whether the design scheme of the double-row pile foundation pit support structure is scientific and reasonable is directly related to the quality, progress, economic benefits and safety of the project, so the rational design of the double-row pile foundation pit support structure is of great significance.

Utility model content

The technical problem to be solved by the utility model is to provide a buttress board type double-row pile foundation pit support structure with convenient construction and high bearing capacity.

The technical solution adopted to solve the above technical problems: a buttress plate type double-row pile foundation pit support structure, including the front row of support piles and the rear row of support piles arranged at intervals along the direction of the side wall of the foundation pit. The pile tops of the front row of support piles and the rear row of support piles all have crown beams, the pile top elevation of the front row of support piles is lower than the pile top elevation of the rear row of support piles, and the front row of support piles and The rear row of support piles are connected by a continuous pile top support plate, and buttress plates are arranged at intervals along the direction of the side wall of the foundation pit between the pile top support plate and the rear row of support piles. There is a water stop pile behind the pile protection.

Further, the front row of support piles and the rear row of support piles are underground continuous walls, and the thickness of the underground continuous walls is 800-1200mm.

Further, the pile top height difference between the front row of support piles and the rear row of support piles is 3.0-6.0m.

Further, the distance between the front row of support piles and the rear row of support piles is 2.5m-5.0m.

Further, the pile diameters of the front row of support piles and the rear row of support piles are 0.8m-2.0m.

Further, the thickness of the pile top support plate is 0.2m-0.5m.

Further, the buttress board has a thickness of 0.3m-0.6m.

Further, the buttress board is a vertical slanting brace, and the two ends of the vertical slanting brace are respectively connected to the crown beams of the front row of support piles and the rear row of support piles.

Beneficial effect: the buttress board type double-row pile foundation pit support structure, by reducing the pile top elevation of the front row of support piles, not only fully exerts the bending resistance of the rear row of support piles, but also reduces the 1 to 2 internal supports to speed up the construction progress of the foundation pit; moreover, the front row of support piles and the rear row of support piles are connected through the pile top support plate and buttress plate, which can transmit the horizontal force of the rear row of support piles to The front row of support piles improves the integrity and overall rigidity of the entire support structure.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the utility model is described further;

Fig. 1 is the elevation view of the first embodiment of the utility model double-row pile foundation pit support structure;

Fig. 2 is the elevation view of the second embodiment of the utility model double-row pile foundation pit support structure;

Figure 3 is a plan view of the utility model double-row pile foundation pit support structure.

Detailed ways

Referring to Figures 1 to 3, the utility model is a buttress board type double-row pile foundation pit support structure, which includes front row support piles 1 and rear row support piles 2 arranged at intervals along the direction of the side wall of the foundation pit. The pile tops of row support pile 1 and rear row support pile 2 all have crown beams 3, the pile top elevation of front row support pile 1 is lower than the pile top elevation of rear row support pile 2, and front row support pile 1 It is connected with the rear row of support piles 2 through a continuous pile top support plate 4, and the pile top support plate 4 and the rear row of support piles 2 are provided with buttress plates 5 at intervals along the direction of the side wall of the foundation pit. A water stop pile 6 is arranged behind the support pile 2 .

Among them, the pile diameters of the front row of support piles 1 and the rear row of support piles 2 can be the same or different, and the pile diameters of the front row of support piles 1 and the rear row of support piles 2 are designed to be 0.8m-2.0m, The front row of support piles 1 and the rear row of support piles 2 can also adopt an underground diaphragm wall structure, the thickness of the underground diaphragm wall is designed to be 800-1200 mm, the width of the crown beam 3 is slightly larger than the pile diameter, and the height of the crown beam is slightly smaller than the pile diameter. path.

The distance between the front row of support piles 1 and the rear row of support piles 2 is designed to be 2.5m to 5.0m, and the pile top height difference between the front row of support piles 1 and the rear row of support piles 2 is based on the The support capacity of 2 is determined, usually designed as 3.0-6.0m, in order to reduce the pile length of the front row of support piles 1, reduce the project cost, widen the excavation progress of the earthwork in the foundation pit, and give full play to the rear row of support piles 2 of bending resistance.

The thickness of the pile top support plate 4 between the front row of support piles 1 and the rear row of support piles 2 is designed to be 0.2m to 0.5m, and the pile top support plate 4 is used as the rigid hinge of the rear row of support piles 2, which can The horizontal force of the support pile 2 is transmitted to the front row of support piles 1, and meanwhile, the pile top support plate 4 is also the foundation of the buttress plate 5. The pile top support plate 4 is a cast-in-place reinforced concrete structure, the concrete strength grade adopts C25-C50, and can be poured together with the crown beam 3 of the front row support pile 1.

The thickness of the buttress board 5 is designed to be 0.3m~0.6m. The buttress board 5 is connected with the pile top support board 4 and the rear row of support piles 2. The buttress board 5 can be a cast-in-place reinforced concrete structure, and the concrete strength grade adopts C25 ~C50. Buttress board 5 can also adopt vertical diagonal brace 7, and the two ends of vertical diagonal brace 7 are respectively connected with crown beam 3 of front row support pile 1 and rear row support pile 2, and vertical diagonal brace 7 can adopt reinforced concrete The structure can also be supported by steel. When using steel support, pre-loading should be applied after the first internal support reaches the design strength, so as to reduce the deformation of the rear row of support piles 2.

Preferably, a shotcrete layer 8 is set in front of the rear support pile 2, the thickness of the shotcrete layer 8 is 0.08-0.10m, the strength level of the shotcrete is not lower than C20, and the shotcrete is equipped with steel mesh, and the steel mesh adopts HPB300 grade Steel bar, steel bar diameter 6-10mm, steel bar spacing 100-250mm.

The embodiments of the present utility model have been described in detail above in conjunction with the accompanying drawings, but the present utility model is not limited to the above-mentioned embodiments. Various changes are made.

Claims (8)

1. A kind of 1. board-like double-row pile foundation pit support structure of counterfort, it is characterised in that：Including being set along foundation pit side-wall direction time interval The front-seat support pile and heel row support pile put, the stake top of the front-seat support pile and heel row support pile is respectively provided with Guan Liang, before described The stake top absolute altitude for arranging support pile is less than the stake top absolute altitude of heel row support pile, passes through between the front-seat support pile and heel row support pile Continuous stake top supporting plate is connected, and is interval with and helps along foundation pit side-wall direction between the stake top supporting plate and heel row support pile Wallboard, water-seal pile is provided with after arranging support pile in the rear.
2. 2. the board-like double-row pile foundation pit support structure of counterfort according to claim 1, it is characterised in that：The front-seat support pile It is diaphram wall with heel row support pile, the thickness of the diaphram wall is 800~1200mm.
3. 3. the board-like double-row pile foundation pit support structure of counterfort according to claim 1, it is characterised in that：The front-seat support pile Stake top difference in height between heel row support pile is 3.0~6.0m.
4. 4. the board-like double-row pile foundation pit support structure of counterfort according to claim 1, it is characterised in that：The front-seat support pile Spacing distance between heel row support pile is 2.5m~5.0m.
5. 5. the board-like double-row pile foundation pit support structure of counterfort according to claim 1, it is characterised in that：The front-seat support pile Stake footpath with heel row support pile is 0.8m~2.0m.
6. 6. the board-like double-row pile foundation pit support structure of counterfort according to claim 1, it is characterised in that：The stake top supporting plate Thickness be 0.2m~0.5m.
7. 7. the board-like double-row pile foundation pit support structure of counterfort according to claim 1, it is characterised in that：The thickness of the counterfort plate Spend for 0.3m~0.6m.
8. 8. the board-like double-row pile foundation pit support structure of counterfort according to claim 1, it is characterised in that：The counterfort plate is perpendicular To diagonal brace, the Guan Liang of the vertical diagonal brace both ends respectively with front-seat support pile and heel row support pile is connected.