阅读说明：本技术 一种不排水沉井下沉的施工方法 (Construction method for sinking of non-drainage open caisson ) 是由 项恒 胡小峰 李红涛 宋艳青 崔炎锋 刘祖新 方晓瑞 罗娟 祝晓迪 李瑞娟 雒慧 于 2021-09-23 设计创作，主要内容包括：本发明公开了一种不排水沉井下沉的施工方法,包括以下步骤：沉井预制步骤：首先勘测一个直径2.5米的工作坑,将沉井的第一节刃脚、第二节刃脚、第三节刃脚、底梁、隔墙分次浇筑成型,然后采用垫脚法在刃脚下设垫木垫层,垫木下再设砂垫层,逐层扩大,然后再将沉井井壁浇筑制作成型。本发明通过施重处理步骤,能够加快沉井下沉的速度,加快了整体加工的速度,通过沉井助沉步骤,能够对下沉速度更进一步加快,同时避免出现偏移的现象,从而达到可以稳定下沉的效果,解决了现有的沉井在使用不排水下沉法时由于内外的水压差过大,在下沉的途中很容易出现倾斜、不均匀沉降和凸沉等问题,导致沉井下沉质量得不到保障的问题。(The invention discloses a construction method for sinking a non-drainage open caisson, which comprises the following steps: an open caisson prefabricating step: firstly surveying a working pit with the diameter of 2.5 meters, pouring and forming a first section of edge foot, a second section of edge foot, a third section of edge foot, a bottom beam and a partition wall of the open caisson by times, then arranging a skid bed under the edge feet by adopting a foot-padding method, arranging a sand bed under the skid, expanding layer by layer, and then pouring and forming the wall of the open caisson. The sinking speed of the open caisson can be accelerated through the step of weighting treatment, the overall processing speed is accelerated, the sinking speed can be further accelerated through the step of assisting sinking of the open caisson, and the phenomenon of deviation is avoided, so that the effect of stable sinking is achieved, and the problem that the sinking quality of the open caisson cannot be guaranteed because the problems of inclination, uneven sedimentation, convex sedimentation and the like are easy to occur in the sinking process due to overlarge water pressure difference between the inside and the outside when the existing open caisson is used in a non-drainage sinking method is solved.)

1. A construction method for sinking a non-drainage open caisson is characterized by comprising the following steps: the method comprises the following steps: the open caisson prefabricating method comprises the steps of a) open caisson prefabricating; b) erecting a water injection pipe; step c) applying weight treatment; d) assisting sinking of the open caisson; step e) soil body reinforcement; step f), sealing the concrete bottom;

step a) open caisson prefabrication: firstly surveying a working pit with the diameter of 2.5 meters, pouring and forming a first section of edge foot, a second section of edge foot, a third section of edge foot, a bottom beam and a partition wall of the open caisson by times, then arranging a skid bed course under the edge feet by adopting a foot-padding method, arranging a sand bed course under the skid, expanding layer by layer, and then pouring and forming the wall of the open caisson;

step b) erecting a water injection pipe: water jetting pipes are arranged along the periphery of the open caisson, and water is jetted to soil around the open caisson at high pressure in a sectional water injection mode to cut and soften the soil in the side wall area of the open caisson;

step c) applying weight treatment: placing two crawler grab shovels at the top of the open caisson, respectively arranging the two crawler grab shovels between two buttress piers of two side walls on two sides, and supporting the grab shovels by adopting prefabricated steel movable platforms to realize moving and grabbing soil;

step d), sinking assistance of the open caisson: thixotropic slurry is injected to the outer side of the wall of the open caisson by a slurry pump to assist sinking, and the open caisson is corrected in the sinking assisting process;

step e) soil body reinforcement: after the open caisson is sunk to a designed position, grouting is carried out on the soil outside the open caisson by a water jetting pipe in a retreating type sectional grouting mode, and the soil outside the open caisson is reinforced;

step f) concrete bottom sealing: and after the reinforcement treatment is finished, the crawler grab shovel machine is taken out, and then concrete is injected into the bottom of the open caisson through the grouting pump for bottom sealing.

2. The construction method for sinking a non-draining open caisson according to claim 1, wherein: step a) open caisson prefabrication, wherein the integral prefabrication adopts a sectional prefabrication mode and is required to be sequentially installed.

3. The construction method for sinking a non-draining open caisson according to claim 1, wherein: step b), erecting a water injection pipe, wherein a plurality of water injection holes are formed in the periphery of the water injection pipe at intervals, a plurality of rows are formed in the length direction of the water injection pipe, the distance between every two adjacent water injection holes is 5-10mm, the distance between every two adjacent water injection holes is 10-15mm, and the diameter of each water injection hole is 1 mm.

4. The construction method for sinking a non-draining open caisson according to claim 1, wherein: and c) applying weight, wherein the hoisting height of the crawler grab shovel machine is 10m, and the crawler grab shovel machine works for medium-grade hoisting.

5. The construction method for sinking a non-draining open caisson according to claim 1, wherein: and d) assisting sinking of the open caisson, wherein the mud injected by the mud pump is quantitatively injected according to the size of the outer side of the open caisson wall, so that excessive mud injection is avoided.

6. The construction method for sinking a non-draining open caisson according to claim 1, wherein: and e) soil body reinforcement, wherein a grouting pipe is adopted during grouting reinforcement, and the grouting pipe has certain pressure resistance.

7. The construction method for sinking a non-draining open caisson according to claim 1, wherein: and f) sealing the bottom with concrete, wherein muddy water glass double grout is sprayed during bottom sealing, so that the soil body is quickly solidified and compacted, and the soil body and the open caisson are adhered by the double grout.

8. The construction method for sinking a non-draining open caisson according to claim 7, wherein: and f) sealing the bottom of the concrete, and performing air drying treatment on the cement glass double-slurry through an air drying device after spraying the cement glass double-slurry.

Technical Field

The invention relates to the technical field of open caisson, in particular to a construction method for sinking an open caisson without draining water.

Background

The open caisson is a well tubular structure, but when the existing open caisson is used in a non-drainage sinking method, the problems of inclination, uneven settlement, convex settlement and the like easily occur in the sinking process due to overlarge water pressure difference between the inside and the outside, so that the sinking quality of the open caisson cannot be guaranteed.

Disclosure of Invention

In order to solve the problems in the background art, the invention aims to provide a construction method for sinking a non-drainage open caisson, which has the advantage of stable sinking and solves the problem that the sinking quality of the open caisson cannot be guaranteed because the existing open caisson is easy to incline, unevenly sink, convexly sink and the like in the sinking process due to overlarge difference between the internal water pressure and the external water pressure when the non-drainage sinking method is used.

In order to achieve the purpose, the invention provides the following technical scheme: a construction method for sinking a non-drainage open caisson comprises the following steps: the open caisson prefabricating method comprises the steps of a) open caisson prefabricating; b) erecting a water injection pipe; step c) applying weight treatment; d) assisting sinking of the open caisson; step e) soil body reinforcement; step f), sealing the concrete bottom;

step a) open caisson prefabrication: firstly surveying a working pit with the diameter of 2.5 meters, pouring and forming a first section of edge foot, a second section of edge foot, a third section of edge foot, a bottom beam and a partition wall of the open caisson by times, then arranging a skid bed course under the edge feet by adopting a foot-padding method, arranging a sand bed course under the skid, expanding layer by layer, and then pouring and forming the wall of the open caisson;

step b) erecting a water injection pipe: water jetting pipes are arranged along the periphery of the open caisson, and water is jetted to soil around the open caisson at high pressure in a sectional water injection mode to cut and soften the soil in the side wall area of the open caisson;

step c) applying weight treatment: placing two crawler grab shovels at the top of the open caisson, respectively arranging the two crawler grab shovels between two buttress piers of two side walls on two sides, and supporting the grab shovels by adopting prefabricated steel movable platforms to realize moving and grabbing soil;

step d), sinking assistance of the open caisson: thixotropic slurry is injected to the outer side of the wall of the open caisson by a slurry pump to assist sinking, and the open caisson is corrected in the sinking assisting process;

step e) soil body reinforcement: after the open caisson is sunk to a designed position, grouting is carried out on the soil outside the open caisson by a water jetting pipe in a retreating type sectional grouting mode, and the soil outside the open caisson is reinforced;

step f) concrete bottom sealing: and after the reinforcement treatment is finished, the crawler grab shovel machine is taken out, and then concrete is injected into the bottom of the open caisson through the grouting pump for bottom sealing.

Preferably, the open caisson is prefabricated in the step a), and the integral prefabrication is performed in a sectional prefabrication mode and needs to be sequentially installed.

Preferably, the water injection pipe is erected in the step b), a plurality of water injection holes are formed in the periphery of the water injection pipe at intervals, a plurality of rows of water injection holes are formed along the length direction of the water injection pipe, the distance between every two adjacent water injection holes is 5-10mm, the distance between every two adjacent water injection holes is 10-15mm, and the diameter of each water injection hole is 1 mm.

Preferably, in the step c), the weight is applied, the hoisting height of the crawler grab shovel is 10m, and the crawler grab shovel works for medium-grade hoisting.

Preferably, in the step d), the open caisson is assisted in sinking, and the mud injected by the mud pump is quantitatively injected according to the size of the outer side of the wall of the open caisson, so that excessive mud injection is avoided.

Preferably, in the step e), the soil body is reinforced, and a grouting pipe is adopted during grouting reinforcement and has certain pressure resistance.

Preferably, in the step f), the concrete bottom sealing is performed, and muddy water glass double grout is sprayed during the bottom sealing, so that the soil body is rapidly solidified and compacted, and the double grout adheres the soil body and the open caisson.

Preferably, in the step f), the concrete is subjected to back cover, and after the cement-water glass double slurry is sprayed, the concrete is subjected to air drying treatment by an air drying device.

Compared with the prior art, the invention has the following beneficial effects:

according to the invention, through the open caisson prefabricating step, the size, the framework and the structure of the open caisson can be more stable, and the phenomenon of offset and inclination can be prevented, through the step of additionally arranging the water jetting pipe, the soil around the open caisson can be softened more, the open caisson can sink conveniently, through the step of applying weight treatment, the sinking speed of the open caisson can be accelerated, the integral processing speed is accelerated, through the open caisson sinking assisting step, the sinking speed can be further accelerated, and the phenomenon of offset can be avoided, through the soil body reinforcing step, the soil body outside the open caisson can be fastened more, and the phenomenon of collapse can be avoided.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The invention provides a construction method for sinking a non-drainage open caisson, which comprises the following steps: the open caisson prefabricating method comprises the steps of a) open caisson prefabricating; b) erecting a water injection pipe; step c) applying weight treatment; d) assisting sinking of the open caisson; step e) soil body reinforcement; step f), sealing the concrete bottom;

step a) open caisson prefabrication: firstly surveying a working pit with the diameter of 2.5 meters, pouring and forming a first section of edge foot, a second section of edge foot, a third section of edge foot, a bottom beam and a partition wall of the open caisson by times, then arranging a skid bed course under the edge feet by adopting a foot-padding method, arranging a sand bed course under the skid, expanding layer by layer, and then pouring and forming the wall of the open caisson;

step b) erecting a water injection pipe: water jetting pipes are arranged along the periphery of the open caisson, and water is jetted to soil around the open caisson at high pressure in a sectional water injection mode to cut and soften the soil in the side wall area of the open caisson;

step c) applying weight treatment: placing two crawler grab shovels at the top of the open caisson, respectively arranging the two crawler grab shovels between two buttress piers of two side walls on two sides, and supporting the grab shovels by adopting prefabricated steel movable platforms to realize moving and grabbing soil;

step d), sinking assistance of the open caisson: thixotropic slurry is injected to the outer side of the wall of the open caisson by a slurry pump to assist sinking, and the open caisson is corrected in the sinking assisting process;

step e) soil body reinforcement: after the open caisson is sunk to a designed position, grouting is carried out on the soil outside the open caisson by a water jetting pipe in a retreating type sectional grouting mode, and the soil outside the open caisson is reinforced;

step f) concrete bottom sealing: and after the reinforcement treatment is finished, the crawler grab shovel machine is taken out, and then concrete is injected into the bottom of the open caisson through the grouting pump for bottom sealing.

The invention is further set in that the open caisson is prefabricated in the step a), the whole prefabricated open caisson adopts a sectional prefabricated mode, and the open caisson is required to be sequentially installed.

The invention is further set as that in the step b), the water injection pipe is erected, a plurality of water injection holes are arranged at intervals around the water injection pipe, a plurality of rows are arranged along the length direction of the water injection pipe, the distance between every two adjacent water injection holes is 5-10mm, the distance between every two adjacent water injection holes is 10-15mm, and the diameter of each water injection hole is 1 mm.

The invention is further set in the step c) to carry out weight application treatment, the hoisting height of the crawler grab shovel machine is 10m, and the crawler grab shovel machine works for medium-grade hoisting.

The invention is further set in the step d) of assisting sinking of the open caisson, and the mud injected by the mud pump is quantitatively injected according to the size of the outer side of the open caisson wall, so that excessive mud injection is avoided.

The invention is further set as that the soil body is reinforced in the step e), and a grouting pipe is adopted during grouting reinforcement and has certain pressure resistance.

The invention is further set in the step f) concrete bottom sealing, and muddy water glass double-slurry is sprayed during bottom sealing, so that the soil body is quickly solidified and compacted, and the double-slurry adheres the soil body and the open caisson.

The invention is further set in that the concrete bottom sealing in the step f) is carried out, and air drying treatment is carried out on the cement glass double-slurry through an air drying device after the cement glass double-slurry is sprayed.

The working principle and the using process of the invention are as follows: firstly surveying a working pit with the diameter of 2.5 meters, pouring and forming a first section of blade foot, a second section of blade foot, a third section of blade foot, a bottom beam and a partition wall of the open caisson by times, then arranging a skid bed course under the blade foot by a foot-laying method, arranging a sand bed course under the skid, expanding layer by layer, then pouring and forming the wall of the open caisson, then arranging water injection pipes along the periphery of the open caisson, spraying water to the soil body around the open caisson at high pressure by adopting a sectional water injection method, cutting and softening the soil body in the side wall area of the open caisson, placing two crawler grab shovels at the top of the open caisson, respectively arranging the two crawler grab shovels between two supporting piers on two side walls, supporting by adopting a prefabricated steel movable platform and realizing moving soil grabbing by adopting a slurry pump to carry out auxiliary sinking, injecting thixotropic slurry to the open caisson at the outer side of the open caisson wall by adopting a slurry pump, rectifying the open caisson in the auxiliary sinking process, sinking the open caisson to the design position, injecting slurry to the soil body outside the open caisson by adopting a sectional retreating grouting mode through the water injection pipes, and (3) reinforcing the soil outside the open caisson, and after the reinforcing treatment is finished, taking out the crawler-type grab shovel machine and then injecting concrete into the bottom of the open caisson through an injection pump to seal the bottom, so that the effect of stable sinking is achieved.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that changes, modifications, substitutions and alterations can be made in these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.