High slope anchoring pile construction method for single-side limited space

Abstract

The invention discloses a high slope anchoring pile construction method for a single-side limited space, and the construction method comprises the following steps: S1, constructing a temporary support structure, and ensuring the stability of slope excavation by using a temporary enclosure; s2, side slope excavation, S3, anchoring of a pile supporting structure, and S4, earthwork backfilling. A temporary enclosure structure is constructed, and the stability of slope excavation is guaranteed through a temporary enclosure; the slope is cut for the first time to a working platform for constructing the permanent supporting structure, so that a construction machine has enough construction space; constructing a fender post and a crown beam at the working platform, and reserving an anchor cable pipeline and a hanging basket embedded part; the slope is cut for the second time to an operation platform for pre-stressed anchor cable construction, and the requirement that underground construction equipment has enough construction space is met; and the pre-stressed anchor cable is constructed, and then initial tensioning and final tensioning are conducted through the hanging basket. The process is clear and definite, the applicability to single-side limited space construction is high, the work efficiency can be remarkably improved, and the construction quality is effectively enhanced.

Description

Technical Field

[0001] The invention belongs to the technical field of slope anchor pile construction, and in particular relates to a high slope anchor pile construction method for a single-side restricted space. Background Art

[0002] With the continuous development of my country's economy and society, and the continuous advancement of urban planning, construction land resources are becoming increasingly scarce. Many new projects are located near existing buildings, and construction space is restricted. The excavation of the slope of the new project will cause the redistribution of soil stress conditions in the site, which will have a serious impact on the safety of the slope project itself and cause deformation and damage to existing buildings in the surrounding area. It is necessary to conduct a specific analysis of the support scheme for deep slope projects in limited spaces, and to ensure the safety of the slope and surrounding structures by adopting a reliable support scheme.

[0003] When anchor piles are constructed in a single-sided confined space using manual bored piles and pile connection methods, there are problems such as long construction time, complicated procedures, and backward construction methods. Normal drilling equipment cannot be used to construct prestressed anchor cables in a single-sided confined space. The backfill of earthwork is small due to the long manual tamping cycle, and the ordinary backfill method is difficult and has low compaction quality. In order to safely, conveniently and quickly solve the problem of high-slope anchor pile construction methods in single-sided confined spaces, a high-efficiency and high-quality anchor pile construction method is urgently needed. Summary of the invention

[0004] In order to overcome the technical problems in the prior art, the present invention provides a method for constructing high slope anchor piles in a single-sided confined space, which utilizes temporary support of steel sheet piles, graded slope cutting for anchor pile construction, processes a portable hanging basket for tensioning anchor cables, and then uses foam concrete backfilling for construction, thereby solving the above-mentioned technical problems.

[0005] A high slope anchor pile construction method for a single-sided restricted space, the construction method uses temporary support of steel sheet piles, graded slope cutting for anchor pile construction, processes portable hanging baskets to tension anchor cables, and then uses foam concrete backfilling for construction, specifically comprising the following steps:

[0006] S1: According to the geological and hydrological conditions, the slope is excavated in stages and then cut to the temporary steel sheet pile construction equipment operation platform;

[0007] S2: Insert temporary steel sheet piles, construct temporary support and backfill the gap between the slope foot and the permanent support piles;

[0008] S3: Jump pile construction support piles, after entering the crown beam construction process, pre-embed portable hanging basket and prestressed anchor cable casing embedded parts;

[0009] S4: Grading and grading to the prestressed anchor cable construction platform;

[0010] S5: Construction of prestressed anchor cables. Personnel enter the pre-buried portable hanging basket to tension the prestressed anchor cables and hang the net to construct the sprayed anchor surface layer;

[0011] S6: Backfill foam concrete, pour in layers and perform curing operations;

[0012] S7: Remove temporary support of steel sheet piles.

[0013] The above-mentioned method for constructing high-slope anchor piles in a single-sided confined space comprises the following steps: in step S1, excavation is carried out using a slope ratio and a support method according to the hydrogeological conditions; a graded excavation method is used to construct steel sheet piles, support piles and a prestressed anchor cable working platform; support piles are constructed using skipping piles; a portable hanging basket is pre-embedded with embedded parts and prestressed anchor cable casings; and the portable hanging basket is used to initially and finally tension the prestressed anchor cables.

[0014] The above-mentioned method for constructing high slope anchor piles in a single-sided confined space, wherein the temporary steel sheet pile support is a cantilever structure, preferably using Larsen IV type steel sheet piles, and the anchoring depth embedded in the soil meets the stability requirements of the supporting pile slope soil in subsequent steps.

[0015] In the above-mentioned high slope anchor pile construction method for a single-sided confined space, the spacing between the pre-buried anchor bolts of the portable hanging basket is preferably 500 mm, and each pre-buried anchor bolt is accurately positioned.

[0016] The above-mentioned method for constructing high slope anchor piles in a single-sided confined space comprises the following steps: the support piles are constructed by skipping, the spacing between adjacent support piles is not less than 3 times the pile diameter, and the construction time interval between adjacent pile foundations is 36 hours.

[0017] In the above-mentioned high slope anchor pile construction method for a single-sided restricted space, the free end of the prestressed anchor cable is coated with anti-rust oil and covered with a corrugated pipe, and is backfilled with foam concrete.

[0018] In the above-mentioned method for constructing high slope anchor piles in a single-sided confined space, the foam concrete in step S6 is pumped by pipeline or directly pumped, and is poured in blocks and layers. The pouring is performed in a jump-like manner according to the settlement joints. The pouring thickness each time is preferably 1m, and the pouring thickness of each layer is preferably 250mm-1000mm.

[0019] In general, compared with the prior art, the above technical scheme conceived by the present invention can achieve the following beneficial effects: the invention is a high slope anchor pile construction method for single-sided confined space with clear and definite procedures, strong applicability for single-sided confined space construction, and can significantly improve work efficiency and effectively enhance construction quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The specific embodiments of the present invention are further described in detail below with reference to the accompanying drawings, wherein:

[0021] Figure 1 This is a schematic diagram of a high slope anchor pile construction for a single-side restricted space according to the present invention;

[0022] Figure 2 It is a schematic diagram of the graded excavation construction of the slope in the construction method of the present invention;

[0023] Figure 3 This is a schematic diagram of temporary support of steel sheet piles in the construction method of the present invention;

[0024] Figure 4 It is a schematic diagram of secondary excavation of the slope in the construction method of the present invention;

[0025] Figure 5 It is a schematic diagram of the construction of prestressed anchor cables in the construction method of the present invention;

[0026] Figure 6 This is a schematic diagram of backfilling foam concrete in the construction method of the present invention;

[0027] Figure 7 A schematic diagram of removing temporary support of steel sheet piles in the construction method of the present invention;

[0028] In the figure: 1-prestressed anchor cable, 2-crown beam, 3-support pile, 4-sprayed anchor surface layer, 5-steel sheet pile, 6-portable hanging basket, 7-foam concrete. DETAILED DESCRIPTION

[0029] according to Figure 1 As shown, it is a schematic diagram of the construction of high slope anchor piles for single-sided confined space of the present invention, which mainly includes the following steps:

[0030] Step 1: Based on factors such as slope geology and excavation depth, and taking into account the horizontal thrust generated by the backfill support pile 3 soil, design and construct temporary steel sheet pile support, such as Figure 2 and Figure 3 As shown, it is a construction schematic diagram of graded excavation of slope and temporary support of steel sheet piles. By utilizing the bending resistance of Larsen steel sheet piles, the deformation of steel sheet piles 5 is monitored at intervals, and the soil between the piles is backfilled to ensure the pile foundation construction platform. When constructing the crown beam 2, the portable hanging basket 6 anchor bolts are simultaneously pre-buried. They are made of bent round steel, and the prestressed anchor cable 1 casing is pre-buried and installed.

[0031] Step 2: After the crown beam 2 reaches the designed strength, carry out secondary slope excavation and transfer the anchor cable drilling machine operating platform from the top to the bottom of the foundation pit, effectively solving the problem of no operating space. Figure 4 The figure shows the schematic diagram of the construction of the secondary excavation of the slope.

[0032] Step 3: Install portable hanging baskets 6 at certain intervals on the crown beam 2, and move the portable hanging baskets 6 to perform subsequent anchor tensioning after the tensioning of a single anchor cable is completed. Figure 5 , which is a schematic diagram of the construction of the prestressed anchor cable 1 of the present invention;

[0033] Step 4: To ensure that the prestressed anchor cable 1 is not eroded by the external environment and thus causes wire breakage, the outer side of the free end is coated with anti-rust oil, a protective sleeve is provided, and grouting is performed after tensioning is completed;

[0034] Step 5: To ensure the compaction quality of the soil in the secondary excavation pit space, foam concrete 7 is used to replace traditional mechanical and manual backfilling to reduce construction period and quality risks. Figure 6 , which is a schematic diagram of the construction of backfilling of the foamed concrete 7 according to the present invention;

[0035] Step 6: After the construction of the foamed concrete 7 is completed, the temporary support of the steel sheet pile 5 is removed, and the load-bearing carrier of the slope is changed from the temporary support to the support pile 3 and the prestressed anchor cable 1 to complete the anchor pile support. Figure 7 As shown, it is a construction schematic diagram of the temporary support removal of the steel sheet pile 5.

Claims

1. A high slope anchor pile construction method for a single-sided restricted space, characterized in that: The construction method uses steel sheet piles (5) for temporary support, graded slope cutting to carry out anchor pile construction, processes a portable hanging basket (6) to tension anchor cables, and then uses foam concrete backfilling to carry out construction, specifically comprising the following steps: S1: According to the geological and hydrological conditions, the slope is excavated in stages and the slope is excavated to the temporary steel sheet pile (5) construction equipment operation platform; S2: Insert temporary steel sheet piles (5), construct temporary support and backfill the gap between the slope foot and the permanent support piles; S3: After the support piles (3) are constructed by jumping piles, the portable hanging basket (6) and the prestressed anchor cable (1) casing embedded parts are pre-embedded after entering the crown beam (2) construction process; S4: Grading to the construction platform of the prestressed anchor cable (1); S5: constructing prestressed anchor cables (1), personnel enter the pre-buried portable hanging basket (6) to tension the prestressed anchor cables, and hang a net to construct the sprayed anchor surface layer (4); S6: backfilling foam concrete (7) by pouring in layers and performing curing operations; S7: Remove the temporary support of steel sheet piles (5).

2. A high slope anchor pile construction method for a single-sided confined space according to claim 1, characterized in that: In the step S1, excavation is performed using a slope ratio and a support method according to the hydrogeological conditions, a steel sheet pile (5), a support pile (3) and a prestressed anchor cable (1) work platform are constructed using a graded excavation method, the support pile (3) is constructed by skipping piles, a portable hanging basket (6) is pre-embedded, and prestressed anchor cable (1) casings are pre-embedded, and the portable hanging basket (6) is used to perform initial and final tensioning of the prestressed anchor cable (1).

3. A high slope anchor pile construction method for a single-sided confined space according to claim 1, characterized in that: The temporary support of the steel sheet pile (5) is a cantilever structure, preferably a Larsen IV type steel sheet pile, embedded in the soil and anchored to a depth that meets the slope soil stability requirements of the support pile (3) in the subsequent steps.

4. A high slope anchor pile construction method for a single-sided restricted space according to claim 1, characterized in that: The spacing between the pre-buried anchor bolts of the portable hanging basket (6) is preferably 500 mm, and each pre-buried anchor bolt is accurately positioned.

5. The method for constructing high slope anchor piles in a single-sided restricted space according to claim 1, characterized in that: The support piles (3) are constructed in a skipped manner, the spacing between adjacent support piles (3) is not less than 3 times the pile diameter, and the construction time interval between adjacent pile foundations is 36 hours.

6. A high slope anchor pile construction method for a single-sided confined space according to claim 1, characterized in that: The free end of the prestressed anchor cable (1) is coated with anti-rust oil and covered with a corrugated pipe, and is backfilled with foam concrete (7).

7. A high slope anchor pile construction method for a single-sided confined space according to claim 1, characterized in that: The foamed concrete (7) in step S6 is pumped by pipeline or directly pumped, and poured in blocks and layers, and poured in jumps according to the settlement joints. The pouring thickness each time is preferably 1m, and the pouring thickness of each layer is preferably 250mm-1000mm.

Images