阅读说明：本技术 一种地基处理方法 (Foundation treatment method ) 是由 刘嘉诚 刘晶 连林 于 2019-09-30 设计创作，主要内容包括：本发明公开了一种地基处理方法,其包括以下步骤：步骤1：测量放样；步骤2：钻孔；步骤3：下放膜袋袖阀管,首先利用高强土工布缝制膜袋,将膜袋的一端采用阀扣绑扎牢固,防止注浆过程中膜袋底端打开,同时自另一端将膜袋收拢至大约一节袖阀管的长度,然后将第一节袖阀管插入膜袋并沿着膜袋每间隔1.5-2.0m绑扎一个阀扣；用人工将制作好的第一节膜袋袖阀管插入钻孔内,依次向膜袋内装入袖阀管,同时每间隔1.5-2.0m制作膜袋外侧的分段注浆阀门,最后一节袖阀管下放完后,用阀扣将膜袋顶端扎牢固,防止注浆过程膜袋顶端打开；步骤4：制备浆液并分段注浆；步骤5：完成最顶端膜袋的注浆后停止注浆。本发明能够限制浆液扩散范围,有利于形成连续、密实的桩体。(The invention discloses a foundation treatment method, which comprises the following steps: step 1: measuring and lofting; step 2: drilling; and step 3: the method comprises the following steps of (1) sewing a membrane bag by utilizing high-strength geotextile, firmly binding one end of the membrane bag by adopting a valve buckle, preventing the bottom end of the membrane bag from being opened in the grouting process, meanwhile, drawing the membrane bag from the other end to the length of about one section of the sleeve valve pipe, then inserting the first section of the sleeve valve pipe into the membrane bag, and binding one valve buckle along the membrane bag at intervals of 1.5-2.0 m; manually inserting the sleeve valve pipe of the first section of the film bag into the drill hole, sequentially filling the sleeve valve pipe into the film bag, simultaneously manufacturing a segmented grouting valve outside the film bag at intervals of 1.5-2.0m, and after the last section of the sleeve valve pipe is lowered down, firmly pricking the top end of the film bag by using a valve buckle to prevent the top end of the film bag from being opened in the grouting process; and 4, step 4: preparing slurry and grouting by sections; and 5: and stopping grouting after grouting of the topmost film bag is completed. The invention can limit the diffusion range of the slurry and is beneficial to forming a continuous and compact pile body.)

1. A foundation treatment method is characterized by comprising the following steps:

step 1: measuring lofting, namely determining the position of each grouting hole by using grouting holes partitioned by a total station instrument and a tape measure according to a design interval, wherein the plane deviation of the hole position meets the design requirement, and making hole position identification;

step 2: drilling, after the drilling machine is in place, leveling the drilling machine by adopting a horizontal ruler matched with a slope ruler, and checking the verticality when the fixed-length depth is reached in the drilling process;

and step 3: the method comprises the following steps of (1) sewing a membrane bag by utilizing high-strength textile geotextile, binding one end of the membrane bag firmly by adopting a valve buckle, preventing the bottom end of the membrane bag from being opened in the grouting process, meanwhile, drawing the membrane bag from the other end to the length of about one section of the sleeve valve pipe, then inserting the first section of the sleeve valve pipe into the membrane bag, and binding one valve buckle at intervals of 1.5-2.0m along the membrane bag; manually inserting the sleeve valve pipes of the first section of the film bag into the drill hole, sequentially filling the sleeve valve pipes into the film bag, simultaneously manufacturing segmented grouting valves on the outer side of the film bag at intervals of 1.5-2.0m, and after the last section of the sleeve valve pipes are lowered, firmly pricking the top end of the film bag by using a valve buckle to prevent the top end of the film bag from being opened in the grouting process;

and 4, step 4: preparing slurry and grouting by sections;

and 5: and stopping grouting after grouting of the topmost film bag is completed.

2. A method of ground treatment according to claim 1, characterized in that: and in the step 3, after the sleeve valve pipe is inserted into the film bag, fixing a plastic drainage plate on the film bag.

3. A method of ground treatment according to claim 2, characterized in that: the plastic drainage plates are fixed on the membrane bag by a sticking or binding method, 1-2 plastic drainage plates are arranged along the length direction of the membrane bag, and when two plastic drainage plates are arranged, the two plastic drainage plates are symmetrically arranged.

4. A method of ground treatment according to claim 1, characterized in that: the diameter of the membrane bag is the same as that of the design pile.

5. A method of ground treatment according to claim 1, characterized in that: and (4) during segmented grouting in the step (4), inserting a grouting gun into the bottom of the sleeve valve pipe, enabling the grouting pump to inject grout into the sleeve valve pipe from bottom to top in a segmented mode, automatically recording the grouting through monitoring the grouting in the grouting process, and controlling the grouting pressure at the sleeve valve pipe orifice within 2.0 MPa.

6. A method of ground treatment according to claim 5, characterized in that: in the step 4, the grouting speed is not required to be too high and is controlled to be about 25L/min.

7. A method of ground treatment according to claim 1, characterized in that: the sleeve valve pipe is a steel pipe.

8. A method of ground treatment according to claim 1, characterized in that: the valve buckle is made of thin iron wires.

Technical Field

The invention relates to the technical field of pile foundation construction, in particular to a foundation treatment method.

Background

In foundation treatment methods for sites such as large-scale house buildings, highways, railways, airport roads and the like, a replacement method, a drainage consolidation method, a CFG pile method and the like are commonly used, and the methods have the defects of long treatment period, high construction cost and the like, so that the methods are limited in engineering application, and the grouting reinforcement technology is widely applied to foundation treatment.

The sleeve valve pipe grouting method is a foundation treatment method which is widely applied, has the characteristics of small construction working face, small traffic influence, easy control and the like, and is widely applied to the construction of highway and field foundation, but the ordinary sleeve valve pipe grouting method is difficult to control the slurry diffusion range in the construction, the phenomena of slurry running, slurry overflow and slurry leakage are easy to occur, the grouting liquid can generate hyperstatic pore water pressure on the foundation, the soil squeezing effect is increased, the foundation is easy to crack or destabilize, and a continuous pile body can not be formed usually.

Disclosure of Invention

The invention aims to provide a foundation treatment method, which can limit the diffusion range of slurry and is beneficial to forming a continuous and compact pile body.

The above object of the present invention is achieved by the following technical solutions:

a method of treating a foundation, comprising the steps of:

step 1: measuring lofting, namely determining the position of each grouting hole by using grouting holes partitioned by a total station instrument and a tape measure according to a design interval, wherein the plane deviation of the hole position meets the design requirement, and making hole position identification;

step 2: drilling, after the drilling machine is in place, leveling the drilling machine by adopting a horizontal ruler matched with a slope ruler, and checking the verticality when the fixed-length depth is reached in the drilling process;

and step 3: the method comprises the following steps of (1) sewing a membrane bag by utilizing high-strength textile geotextile, binding one end of the membrane bag firmly by adopting a valve buckle, preventing the bottom end of the membrane bag from being opened in the grouting process, meanwhile, drawing the membrane bag from the other end to the length of about one section of the sleeve valve pipe, then inserting the first section of the sleeve valve pipe into the membrane bag, and binding one valve buckle at intervals of 1.5-2.0m along the membrane bag; manually inserting the sleeve valve pipes of the first section of the film bag into the drill hole, sequentially filling the sleeve valve pipes into the film bag, simultaneously manufacturing segmented grouting valves on the outer side of the film bag at intervals of 1.5-2.0m, and after the last section of the sleeve valve pipes are lowered, firmly pricking the top end of the film bag by using a valve buckle to prevent the top end of the film bag from being opened in the grouting process;

and 4, step 4: preparing slurry and grouting by sections;

and 5: and stopping grouting after grouting of the topmost film bag is completed.

By adopting the technical scheme, all the sections of the sleeve valve pipe are sequentially placed into the film bag, the valve of the rubber valve on the side wall of the sleeve valve pipe is opened by the pressure of slurry during grouting, the slurry enters the film bag, the film bag is filled with the slurry until the film bag is completely opened, the film bag limits the diffusion of the slurry to the surrounding soil body, and the slurry is condensed to form a continuous and compact pile body from bottom to top.

The invention is further configured to: and in the step 3, after the sleeve valve pipe is inserted into the film bag, fixing a plastic drainage plate on the film bag.

Through adopting above-mentioned technical scheme, the pile body expands because of the slip casting gradually, and this in-process, the soil body is constantly compressed, crowded densely, and the setting of drain bar has also accelerated the discharge of water for the soil body is more closely knit, and intensity also improves greatly. The arrangement of the drainage plate can discharge excess pore water and also discharge redundant free water in soil, thereby reducing the water content of the soil body and reinforcing the foundation to a certain extent.

The invention is further configured to: the plastic drainage plates are fixed on the membrane bag by a sticking or binding method, 1-2 plastic drainage plates are arranged along the length direction of the membrane bag, and when two plastic drainage plates are arranged, the two plastic drainage plates are symmetrically arranged.

Through adopting above-mentioned technical scheme, plastics drain bar sets up two and the symmetry sets up, has strengthened the leakproofness of plastics drain bar to membrane bag parcel.

The invention is further configured to: the diameter of the membrane bag is the same as that of the design pile.

By adopting the technical scheme, the diameter of the membrane bag is consistent with that of the designed pile body, the pile body formed after grouting is tightly attached to the surrounding soil body, and the whole pile and the membrane bag prop open the surrounding soil body, which is similar to a composite foundation, so that the foundation is reinforced.

The invention is further configured to: and (4) during segmented grouting in the step (4), inserting a grouting gun into the bottom of the sleeve valve pipe, enabling the grouting pump to inject grout into the sleeve valve pipe from bottom to top in a segmented mode, automatically recording the grouting through monitoring the grouting in the grouting process, and controlling the grouting pressure at the sleeve valve pipe orifice within 2.0 MPa.

By adopting the technical scheme, the soft soil layer in the foundation can be reinforced in a targeted manner by adopting segmented grouting, so that the construction cost is reduced, and the compactness of the pile body is improved; the grouting pressure is strictly controlled, and the phenomena of film bag breakage, slurry leakage and the like can be avoided.

The invention is further configured to: in the step 4, the grouting speed is not required to be too high and is controlled to be about 25L/min.

By adopting the technical scheme, the phenomenon of water pressure enrichment in the gaps is prevented, and soil body cleavage is prevented.

The invention is further configured to: the sleeve valve pipe is a steel pipe.

By adopting the technical scheme, the composite material has the advantages of low price, high strength and high overall cost performance.

The invention is further configured to: the valve buckle is made of thin iron wires.

Through adopting above-mentioned technical scheme, easy operation is convenient for control ligature elasticity degree moreover.

In conclusion, the beneficial technical effects of the invention are as follows:

1. the outer sides of the sleeves are provided with the film bags, so that the diffusion range of grouting slurry is limited, the phenomena of slurry leakage, slurry mixing and the like are avoided, and a pile body with higher strength can be formed after the slurry is solidified to play a role in supporting the whole roadbed;

2. in the process of filling the slurry into the film bag, along with the continuous increase of the accumulated pressure of the slurry in the film bag, the soil body around the film bag enables the pressure of the water in the super-gap in the soil body to be continuously increased under the action of the horizontal squeezing and expanding force. At the moment, pore water is discharged along with the plastic drainage plate outside the membrane bag, the pressure of the pore water is dissipated, and the effective stress of the soil body is increased, so that the soil body around the membrane bag is gradually compacted, and the strength is improved;

3. because the bottom of the grouting pile body is embedded into the hard soil layer, the soil body settlement rate is far greater than that of the pile body, and the soil body transfers part of load to the pile body through pile side friction force to be laterally borne, so that the soil body settlement can be effectively reduced. Meanwhile, with the continuous compaction of the soil body, the friction force between the soil body and the pile body is also continuously increased;

4. the plastic drainage plate arranged outside the membrane bag can remove the excess pore water generated in the grouting process under the action of the grouting pressure, and can also remove the excess pore water generated by the upper soil filling load and the redundant water in the grouting slurry. The water content of the soil body is reduced, and the strength of the soil body is further improved.

Drawings

FIG. 1 is a schematic view of a construction process flow according to an embodiment of the present invention.

Fig. 2 is a structural diagram of the grouting structure of the sleeve valve pipe of the film bag.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings.

Referring to fig. 1, which is a construction process flow chart of a foundation treatment method disclosed by the invention, the method comprises the following steps:

firstly, testing and lofting, namely dividing grouting hole positions by using a total station, wherein the distance between pile holes is 1m, the pile holes are arranged in a quincuncial pile shape, the position of each grouting hole is determined by using a tape measure according to the designed distance, the plane deviation of the hole positions meets the design requirement, and hole position identification is made.

Then the drilling machine is in place, the drilling machine is installed to ensure that the base is flat and stable, the periphery of the drilling machine contacting the ground is cushioned by hard stones and square timbers, the drilling machine is strictly prohibited from contacting the ground to cause point or local contact, and the drilling machine is temporarily stable so as to avoid the inclination of a drilling hole. Drilling is started, a horizontal ruler is adopted to match with a slope ruler (or a geological compass) to level the drilling machine before drilling, and once verticality test is needed when drilling for 2m and after drilling for 5m each time; during drilling, high-quality mud such as bentonite mud is used for wall protection, and when hole collapse is serious, casing pipe wall protection is used. And measuring the drilling depth after pore forming, and ensuring the verticality of the pile hole while ensuring that the hole depth must meet the design requirement.

Then, a membrane bag is manufactured, referring to fig. 2, the membrane bag in the embodiment is manufactured by processing high-strength geotextile, the breaking strength is more than 2.5k N/cm, the breaking elongation is about 20%, the weight is more than 200g/m2, the cloth bag is folded for three times, double-thread sewing is carried out along a folding area, the geotextile can block cement slurry due to high mesh density, water can pass through under the action of pressure, the length of the membrane bag is preferably about 1m longer than a pile hole, and the diameter of the membrane bag is the same as the diameter of a designed pile body. The sleeve valve tube in this embodiment is a steel tube.

Adopt the valve to detain the ligature firm with the one end of membrane bag, prevent that slip casting in-process membrane bag bottom from opening, draw in the membrane bag to about the length of a section of sleeve valve pipe simultaneously from the other end, then insert in the membrane bag with first section sleeve valve pipe from the membrane pocket mouth that draws in to along every interval 1.5-2.0m ligature valve of membrane bag in detaining, the valve detain can adopt plastics buckle or thin iron wire, adopts thin iron wire in this embodiment. And then fixing 1-2 plastic drainage plates on the membrane bag by adopting a sticking or binding method, wherein the plastic drainage plates are arranged along the length direction of the membrane bag, and when 2 plastic drainage plates are arranged, the 2 plastic drainage plates are symmetrically arranged.

Manually inserting the manufactured first section of film bag sleeve valve pipe into the drill hole, lifting the film bag when the first section of film bag sleeve valve pipe is about 1.5m away from the working surface, and connecting the first section of film bag sleeve valve pipe with the second section of film bag sleeve valve pipe by using quick setting glue; and (3) extending the folded film bag, continuously lowering the sleeve valve pipes, manufacturing a segmented grouting valve outside the film bag at intervals of 1.5-2.0m, and after the last section of sleeve valve pipes are lowered, firmly pricking the top end of the film bag by using a valve buckle to prevent the top end of the film bag from being opened in the grouting process.

Then preparing grouting slurry, and adding all grouting materials into a stirring barrel according to the designed mixing proportion of the slurry; the stirring time of the slurry is not less than 3 min by using a high-speed stirrer; the time for using the ordinary stirrer is not less than 5 min. The time from preparation to exhaustion of the grouting slurry is less than 4 hours; the slurry should be used after sieving and the specific gravity of the slurry is measured by a specific gravity meter at regular time.

And then starting a segmental grouting task, inserting a grouting gun into the bottom of the sleeve valve pipe, adopting a grouting pump to inject grout into the sleeve valve pipe through the grouting gun, and performing segmental grouting from bottom to top. And monitoring the grouting amount of each section by adopting a grouting automatic recorder, and lifting a grouting gun to perform grouting of the next section when the designed dosage of each section is reached. In some projects with strict requirements on foundation deformation, grouting can be carried out twice, the first grouting amount is about 60% of the designed grouting amount of each section, and grouting of the residual 40% of grout is carried out after 6 hours. And closely monitoring the reading of the grouting pressure on the grouting automatic recorder in the grouting process, and controlling the grouting pressure at the pipe orifice of the sleeve valve to be not more than 2.0 MPa.

During grouting, the grouting speed is not required to be too high, and is controlled to be about 25L/min, so that the phenomenon of soil body splitting caused by continuous enrichment of water pressure in a gap is avoided. If the grout does not reach the orifice during grouting and the grout effluvium phenomenon occurs on the ground, the grout leakage phenomenon occurs during grouting of the membrane bag, and secondary grouting is needed. During grouting, a grouting gun is locked in the sleeve valve pipe in the process of lifting the grouting pipe, so that a grouting hole is scrapped and grouting cannot be performed. According to the accumulation of field experience, the grouting gun needs to be lifted up and down before grouting starts after the grouting gun is inserted, and the possibility that the grouting gun is movable in the sleeve valve pipe is guaranteed.

And stopping grouting after the grouting of the topmost section of the film bag is finished, sealing the grouting hole and the geological drilling hole after the grouting is finished, wherein the sealing hole is made of the same material as the grouting.

The embodiments of the present invention are preferred embodiments of the present invention, and the scope of the present invention is not limited by these embodiments, so: all equivalent changes made according to the structure, shape and principle of the invention are covered by the protection scope of the invention.