Inter-pile retaining wall for open construction of fender posts
By using the retaining wall structure between piles made of exposed retaining piles and combining steel casing with cast-in-place piles, the problem of pile deviation during foundation pit construction was solved, construction safety and accuracy were improved, construction period was shortened and costs were reduced.
Patent Information
- Application Number
- CN202422812700.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-18
- Publication Date
- 2025-09-23
- Estimated Expiration
- 2034-11-18
AI Technical Summary
In foundation pit projects, when constructing two overlapping foundation pits, the drilled piles are prone to deviation, causing damage to existing structures and reducing construction safety and accuracy.
The retaining wall structure between piles is made of exposed retaining piles. Steel casing is combined with cast-in-place piles, and an effective connection is formed by welding the steel mesh and steel casing to ensure accurate construction sequence and positioning. The upper retaining wall and pile support are constructed in layers to avoid affecting the existing structure.
It improves construction safety and accuracy, shortens construction period, reduces costs, ensures the verticality and load-bearing performance of cast-in-place piles, and optimizes the stability of the load-bearing structure.
Smart Images
Figure CN223373737U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the field of foundation pit support, in particular to an inter-pile retaining wall used for retaining piles. Background Art
[0002] In foundation pit construction, due to environmental constraints, it is sometimes necessary to construct two overlapping foundation pits that cannot be excavated simultaneously. First, a first foundation pit needs to be excavated. After the structure in the first foundation pit is completed, it is backfilled and then another second foundation pit is excavated.
[0003] However, when backfilling and then excavating the second foundation pit, drilling piles may cause damage to the structure in the first foundation pit. For example, when the location is very limited, high construction accuracy is required, and the drilling piles are prone to deviation, which may cause damage to the existing structure and reduce the safety of construction.
[0004] Therefore, a construction method is needed that is suitable for the above two foundation pits and ensures construction safety. Utility Model Content
[0005] The utility model aims to provide an inter-pile retaining wall for enclosing piles, wherein the upper part of the structure adopts an exposed construction method, which simplifies the construction steps, shortens the construction period and reduces the cost.
[0006] To achieve the above-mentioned purpose, the utility model adopts the following technical solution: a retaining wall between piles for retaining piles, comprising a plurality of retaining piles, each of which comprises a steel casing and a cast-in-place pile, the lower end of the steel casing being embedded in the bottom of a first foundation pit, the upper part of the cast-in-place pile being arranged in the steel casing, the lower end of the cast-in-place pile being embedded in the bottom of a second foundation pit, and an upper retaining wall being provided between adjacent steel casings.
[0007] The beneficial effects of this program are:
[0008] 1. After completing the construction in the first foundation pit, embed the lower end of the steel casing into the bottom of the first foundation pit; then cast the upper retaining wall between the steel casings in layers, and backfill the first foundation pit at the same time; next, drill holes and cast cast-in-place piles starting from the bottom of the steel casing. Since the depth of the second foundation pit is usually greater than that of the first foundation pit, the depth of the cast-in-place piles is greater than that of the steel casing, and they are directly embedded in the bottom of the second foundation pit; finally, excavate the second foundation pit in stages and step by step, remove the original support of the first foundation pit close to the second foundation pit, excavate the backfill soil and the soil under the upper retaining wall, construct support between piles, and support the soil in the part of the second foundation pit that is lower than the first foundation pit.
[0009] 2. In this plan, after the construction of the first foundation pit is completed, in order to ensure the safety of the implemented structure, before backfilling the first foundation pit, the steel casing and upper retaining wall (as support for the second foundation pit) located in the first foundation pit are first completed, and then the first foundation pit is backfilled, and then piles are drilled through the steel casing. This ensures that when the second foundation pit is constructed, it will not affect the newly built structure in the first foundation pit.
[0010] 3. The retaining piles are positioned by steel casing to guide the subsequent drilling, ensuring the verticality of the cast-in-place piles and improving the stress-bearing performance of the cast-in-place piles.
[0011] Furthermore, the upper retaining wall includes several layers of steel mesh, which are connected to the steel casing.
[0012] Furthermore, the steel mesh includes an inner steel mesh and an outer steel mesh. The inner steel mesh is horizontally arranged, two sides of the inner steel mesh are respectively connected to the steel casing, and the remaining two sides of the inner steel mesh are respectively connected to the outer steel mesh, and the outer steel mesh is vertically arranged.
[0013] Furthermore, the interlayer spacing of the steel mesh is 25-35 cm.
[0014] Furthermore, inter-pile supports are provided between the lower parts of adjacent cast-in-place piles, and the inter-pile supports are connected to the upper retaining wall. The upper retaining wall is constructed upwards using a forward construction method, and the inter-pile supports are constructed downwards using a reverse construction method.
[0015] Furthermore, a steel section limiting device is provided at the upper end of the steel casing, and the steel section limiting device is fixedly connected to the edge of the first foundation pit.
[0016] This solution also has the following effects:
[0017] 1. In the prior art, steel bars are usually reserved at the connection position of two reinforced concrete structures, and the connection of the two structures is achieved by steel bar connection. However, in this solution, since steel casing is used on the upper part of the retaining piles, the reserved steel bars cannot directly pass through the steel casing and form an effective connection with the steel mesh of the upper retaining wall. After the foundation pit is excavated, it will slip under the action of soil pressure. Therefore, the steel mesh and the steel casing are directly welded to form a connection; the retaining wall and the steel casing form an effective connection, so that they work together with the retaining piles and bear the force together.
[0018] 2. This solution separates the inner and outer layers of steel mesh from the steel mesh, which are effectively connected to the steel casing through welding to coordinate the force. The inner and outer layers of steel mesh are welded to the steel casing from different angles to avoid the welding positions being concentrated in the same direction of the steel casing, thereby optimizing the force structure and ensuring the stability of the structure.
[0019] In addition, inner steel bars are used to connect the outer steel mesh on both sides of the steel casing to further fix the outer steel bars.
[0020] 3. When the depth of the second foundation pit is greater than that of the first foundation pit, the support between the retaining piles is divided into two parts, upper and lower, so that construction can be carried out at the most appropriate time: the upper retaining wall is constructed before the backfilling of the first foundation pit, which is convenient and quick, and there is no need to consider the stability of the slope; the support between the piles is constructed after the second foundation pit is excavated. Compared with the construction before the backfilling of the first foundation pit, the soil below the first foundation pit does not need to be excavated, thereby reducing the amount of unnecessary excavation. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 is a schematic diagram of an embodiment;
[0022] Figure 2 This is a schematic diagram of the first foundation pit before backfilling applicable to the embodiment;
[0023] Figure 3 This is a schematic diagram of the embodiment after the first foundation pit is backfilled and before the second foundation pit is excavated;
[0024] Figure 4 This is a schematic diagram of the second foundation pit after excavation applicable to the embodiment. DETAILED DESCRIPTION
[0025] The following is further described in detail through specific implementation methods:
[0026] The figure marks in the drawings of the specification include: steel casing 1, cast-in-place piles 2, underground passage 3, outer steel mesh 4, inner steel mesh 5, steel limit device 6, first foundation pit 7, second foundation pit 8, retaining wall between piles 9, backfill 10, new box culvert 11.
[0027] Example
[0028] The embodiment is basically as follows Figure 1 As shown: A retaining wall between piles for retaining piles, suitable for Figure 4 The partially overlapping first foundation pit 7 and second foundation pit 8 are constructed. In this embodiment, the first foundation pit 7 is a drainage foundation pit for the second foundation pit 8. The depth of the second foundation pit 8 is greater than that of the first foundation pit 7. This embodiment includes a number of retaining piles, each of which includes a steel casing 1 and a cast-in-place pile 2. Figure 1 The top middle view is a top view. Figure 1 The lower middle part is the main view. The steel casing 1 is made of steel. The lower end of the steel casing 1 is embedded in the bottom of the first foundation pit 7. The cast-in-place pile 2 is a concrete structure. The upper part of the cast-in-place pile 2 is cast in the steel casing 1. The lower end of the cast-in-place pile 2 is embedded in the bottom of the second foundation pit 8. An upper retaining wall is provided between adjacent steel casings 1.
[0029] The upper retaining wall is made of reinforced concrete. Figure 1Only the steel bar part of the upper retaining wall is shown; the upper retaining wall includes two layers of vertically arranged outer steel mesh and several horizontally arranged inner steel mesh 5, the layer spacing of the inner steel mesh is 25-35cm, and the layer spacing in this embodiment is 30cm. The two sides of the inner steel mesh 5 are respectively welded to the steel casing 1, and the remaining two sides of the inner steel mesh 5 are respectively welded to the two layers of outer steel mesh 4, and the adjacent outer steel mesh 4 are tied and connected. The two layers of outer steel mesh 4 are respectively located on both sides of the steel casing 1 and welded to the steel casing 1.
[0030] Inter-pile support is also provided between the lower parts of adjacent cast-in-place piles 2. The inter-pile support is a baffle or shotcrete. In this embodiment, the inter-pile support adopts the existing construction method of the inter-pile baffle. The top of the inter-pile support is connected to the bottom of the upper retaining wall. The upper retaining wall is formed by upward construction using the forward construction method, and the inter-pile support is formed by downward construction using the reverse construction method.
[0031] The upper end of the steel casing 1 is welded with a steel limiter 6, which is an I-beam. Figure 2 As shown, a steel plate is pre-buried at the left edge of the first foundation pit 7, and the left end of the steel section limiting device 6 is welded to the steel plate.
[0032] A method for installing an inter-pile retaining wall with exposed piles is as follows:
[0033] 1. Such as Figure 2 As shown, the first foundation pit 7 is supported by the retaining wall 9 between piles. Steel plates are embedded in the upper ends of the retaining walls 9 between piles on both sides of the first foundation pit 7. The old box culvert in the first foundation pit 7 is dug out and a new box culvert 11 is built. Figure 2 The dotted line in FIG represents the structure designed and built in the second foundation pit 8. In this embodiment, the structure designed and built is an underground passage 3; Figure 3 As shown, the lower end of the steel casing 1 is embedded in the bottom of the first foundation pit 7, the upper end of the steel casing 1 is welded to the steel limit device 6, and the two ends of the steel limit device 6 are respectively welded to the steel plates on both sides;
[0034] 2. Then install the steel mesh in layers and cast the upper retaining wall between the steel casings 1, using the forward construction method to construct upwards, while backfilling the first foundation pit in layers;
[0035] 3. Next, drill and cast the cast-in-place pile 2 starting from the bottom of the steel casing 1;
[0036] 4. Such as Figure 4 As shown, finally, the second foundation pit 8 is excavated in stages and gradually. The existing retaining wall 9 between piles near the second foundation pit 8 of the first foundation pit 7 is removed. The portion of the steel limiter 6 that intrudes into the second foundation pit 8 is cut. The backfill 10 and the soil below the upper retaining wall are excavated, and the support between piles is constructed downward using a reverse construction method. Finally, the underground passage 3 within the second foundation pit 8 is constructed.
[0037] The above description is merely an embodiment of the present invention, and the commonly known specific technical solutions and / or features of the solution are not described in detail here. It should be noted that for those skilled in the art, without departing from the technical solution of the present invention, several variations and improvements can be made, which should also be considered as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection claimed in this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.
Claims
1. A retaining wall between piles for retaining piles, characterized by: It includes several retaining piles, each of which includes a steel casing and a cast-in-place pile. The lower end of the steel casing is embedded in the bottom of the first foundation pit, the upper part of the cast-in-place pile is arranged in the steel casing, and the lower end of the cast-in-place pile is embedded in the bottom of the second foundation pit. An upper retaining wall is provided between adjacent steel casings.
2. The retaining wall between piles for retaining piles according to claim 1, characterized in that: The upper retaining wall includes several layers of steel mesh, which are connected to the steel casing.
3. The retaining wall between piles for retaining piles according to claim 2, characterized in that: The steel mesh includes an inner steel mesh and an outer steel mesh. The inner steel mesh is arranged horizontally, two sides of the inner steel mesh are connected to the steel casing respectively, and the remaining two sides of the inner steel mesh are connected to the outer steel mesh respectively. The outer steel mesh is arranged vertically.
4. The retaining wall between piles for retaining piles according to claim 2, characterized in that: The interlayer spacing of the steel mesh is 25-35cm.
5. The retaining wall between piles for retaining piles according to claim 4, characterized in that: Inter-pile supports are provided between the lower parts of adjacent cast-in-place piles, and the inter-pile supports are connected to the upper retaining wall. The upper retaining wall is constructed upwards using the forward construction method, and the inter-pile supports are constructed downwards using the reverse construction method.
6. The retaining wall between piles for retaining piles according to claim 5, characterized in that: A steel section limiting device is provided at the upper end of the steel casing, and the steel section limiting device is fixedly connected to the edge of the first foundation pit.