Reinforcing method for soft soil foundation

Abstract

The invention relates to the technical field of foundation reinforcement processes, and discloses a soft soil foundation reinforcement method which comprises the following steps: step 1, cleaning a construction area to flatten the surface of soft soil, then arranging pile positions on the surface of the soft soil, and inserting and driving bamboo sheet piles on the pile positions as marks; and then the vibroflot is installed, in-place adjustment is conducted, and it is guaranteed that the vibroflot and the soft soil layer are in a vertical state. A soft soil layer is compacted while soft soil is subjected to pore forming through the vibroflot, cement mortar is conveyed into the vibroflot through a mortar pump, a cement conveying pipe and other components, the cement mortar can be sprayed out of spraying holes of the vibroflot and sputtered into a pile channel and the inner wall of the pile channel, then gravel is injected into the pile channel, the gravel is stirred, and then a pile foundation is formed. The strength of the soft soil foundation can be greatly improved, so that the bearing capacity of the soft soil is improved, and the whole process is simple in construction technology and high in efficiency.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of foundation reinforcement, in particular to a soft soil foundation reinforcement method. BACKGROUND

[0002] In the process of house construction, because some soft soil foundations cannot meet the requirements of building bearing capacity, effective reinforcement measures should be taken for the soft soil foundation to ensure the stability of the building. In order to meet the needs of different foundation treatment requirements, various foundation treatment methods have been developed, such as vacuum preloading method, deep mixing method, vibration compaction method, freezing method, and concrete core gravel pile method.

[0003] According to the search, the Chinese patent document No. CN111705777A discloses a method for reinforcing soft soil foundation. The baffle is punched into the both sides of the drainage plate, and the baffle blocks the drainage plate to play a sealing role. As the upper layer of water is pumped out, the baffle is gradually punched deep, and the part of the drainage plate blocked by the baffle is more and more, so that the vacuum load under the membrane is gradually concentrated in the lower part of the drainage plate not blocked by the baffle, so as to enhance the suction of the lower part of the drainage plate, thereby ensuring the vacuum effect of deep soft soil and improving the reinforcement effect of soft soil foundation. However, the above-mentioned reinforcement method needs to punch the water stop curtain and the drainage plate into the soft soil in turn, and then needs to lay the vacuum website, and finally needs to lay the steps of woven cloth, non-woven fabric and sealing film. The process is complicated, and the effect obtained after construction is only to improve the vacuum effect of soft soil, and the reinforcement effect is not greatly improved. SUMMARY

[0004] (I) Technical problems solved

[0005] In view of the deficiencies of the prior art, the present application provides a soft soil foundation reinforcement method, which has the advantages of simple construction process, improved stress distribution of soil body, improved bearing capacity of soft soil foundation, and guaranteed strength of soft soil foundation. The problems of complex construction process if the reinforcement is appropriate, and the problem of unsatisfactory reinforcement effect if the construction is simple are solved.

[0006] (II) Technical solutions

[0007] In order to achieve the above-mentioned purpose of simple construction process, improved stress distribution of soil body, improved bearing capacity of soft soil foundation, and guaranteed strength of soft soil foundation, the present application provides the following technical solutions: a soft soil foundation reinforcement method, which is carried out according to the following steps:

[0008] Step 1: clean the construction area to make the surface of the soft soil flat, then lay the pile position on the surface of the soft soil, and insert the bamboo chip pile as a marker on the pile position;

[0009] Step two: excavate a trench at the pile position, then install a vibrator and make in-situ adjustment to ensure that the vibrator is perpendicular to the soft soil layer, the outer surface of the vibrator is provided with a plurality of spray holes, the inside of the vibrator is hollow, and the top of the vibrator is connected with a pipe head;

[0010] Step three: connect the pipe head with a cement delivery pipe, the cement delivery pipe is connected with a mortar pump for delivering cement mortar;

[0011] Step four: start the hole making operation, start the vibrator to continuously penetrate into the deep layer of soft soil until the hard soil layer is reached, in the process, the vibrator extrudes the soft soil to make it dense, and forms a pile channel in the soft soil;

[0012] Step five: after the bottom of the vibrator reaches the hard soil layer, start to withdraw, in the process, the mortar pump cooperates with the cement delivery pipe and the pipe head to pour the cement mortar into the inside of the vibrator, and then the cement mortar is sprayed from the spray holes into the pile channel;

[0013] Step six: after the vibrator is completely withdrawn, add gravel from the top of the pile channel, and use a crane to insert a vibrating and stirring rod into the pile channel to vibrate and stir the cement and gravel;

[0014] Step seven: after the cement mixed with gravel in the pile channel and completely dried, the surface of the soft soil is tamped to complete the reinforcement of the soft soil foundation.

[0015] Preferably, the step one further comprises geological survey and soil test of the soft soil to obtain the distance from the surface of the soft soil to the hard soil layer, and the interval of the pile position is 2-3m.

[0016] Through the above technical scheme, the geological survey of the soft soil is needed before the pile position is laid on the soft soil, so as to measure the depth and soil composition of the soft soil, so that the appropriate equipment is selected for the following reinforcement operation, the pile position is laid at an interval of 2-3m, and the pile positions are arranged in an equilateral triangle, so that the pile positions are uniformly and densely distributed in the construction area, and the reinforcement effect is good.

[0017] Preferably, the hole making speed of the vibrator in the step four is controlled at 0.5-2.0m / min.

[0018] Through the above technical scheme, the depth of the trench excavated in step two can bury the conical head of the vibrator in the soft soil, and then start the vibrator to continuously penetrate into the soft soil by vibration, and the soft soil can be compacted during the vibration process, so that the soft soil is compacted and the bearing capacity of the soft soil is increased, the hole making speed is controlled between 0.5-2.0m / min, the soft soil is fully vibrated and compacted under the premise of ensuring the efficiency, and the vibrator 1 stops vibrating when it contacts the underground hard soil layer, so that the pile channel is formed.

[0019] Preferably, the output end of the mortar pump is connected to the cement delivery pipe, and the volume formula for injecting the cement mortar into the pile channel is:

[0020] v = π r 2 h x β

[0021] wherein v is the injection amount of the cement mortar, r is the radius of the pile channel, h is the height of the pile channel, and β is the mixing amount coefficient (i.e., the proportion of the cement amount to the volume weight of the pile channel).

[0022] Through the above technical solution, the vibrator is withdrawn using the crane, and in the process of withdrawal, the mortar pump is started to draw the cement mortar into the cement delivery pipe, and then the cement mortar enters the inside of the vibrator, and with the increase of the pressure, the cement mortar is sprayed from the spray hole to splash into the inside of the pile channel and on the inner wall.

[0023] Preferably, the cement mortar composition is water, cement and sand, and the proportion of water, cement and sand is 2:2:1.

[0024] Through the above technical solution, the water, cement and sand are mixed in a ratio of 2:2:1 to make the cement mortar, which ensures that the cement mortar has good flowability, facilitates the spraying of the cement mortar from the inside of the vibrator, and also has good strength after being mixed with sand and stone to form a shape, thereby playing a role in strengthening the soft soil foundation.

[0025] Preferably, the amount of sand and stone added in step six is one-third of the injection amount of the cement mortar, and the diameter of the sand and stone is 50-60mm.

[0026] Through the above technical solution, after the vibrator is completely withdrawn from the pile channel, the sand and stone are filled into the inside of the pile channel using a shovel car and other equipment, and the filling is performed several times, and in the filling process, the cement and sand and stone are mixed using a vibrating stirring rod.

[0027] Preferably, the vibrating stirring rod comprises a shell, a motor, a rotating shaft, an eccentric block and a stirring paddle, the motor is installed in the shell, the output shaft of the motor is connected to the rotating shaft through a coupling, the outer surface of the rotating shaft is fixedly connected to the eccentric block, and the bottom end of the rotating shaft is fixedly connected to the stirring paddle.

[0028] Through the above technical scheme, the motor is started to drive the rotating shaft to rotate, the rotating shaft drives the eccentric block to make eccentric motion, the eccentric block drives the shell to vibrate, so that the gravel is accelerated to sink into the bottom of the pile passage, and vibrating and vibrating the cement mortar can promote mixing, at the same time, the rotating shaft drives the stirring paddle to rotate to further improve the mixing efficiency, and the soft soil in the inner wall of the pile passage can be driven in the process of stirring, so that the cement mortar, gravel and soft soil are closely combined.

[0029] Preferably, the step seven further comprises filling the top of the pile passage with fillers, and the fillers are concrete.

[0030] Through the above technical scheme, after the cement mortar in the pile passage is completely dried, the top of the trench excavated in step two, that is, the top of the pile passage, needs to be filled with fillers, the fillers are concrete, and the trench is completely filled with the fillers and steel bars, and after drying, the soft soil surface is tamped, so that the soft soil surface is compacted, and the compactness of the soft soil is further improved.

[0031] Compared with the prior art, the present application provides a method for reinforcing soft soil foundation, which has the following advantages:

[0032] 1. The method for reinforcing soft soil foundation provided by the present application can greatly improve the strength of the soft soil foundation, thereby improving the bearing capacity of the soft soil, and the whole process is simple in construction process and high in efficiency.

[0033] 2. The method for reinforcing soft soil foundation provided by the present application can greatly improve the strength of the soft soil foundation, thereby improving the bearing capacity of the soft soil, and the whole process is simple in construction process and high in efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0034] Fig. 1 The flowchart of the method of the present application is shown in the figure;

[0035] Fig. 2 The working schematic diagram of the structure of the vibrator of the present application is shown in the figure;

[0036] Fig. 3The sectional view of the structure of the vibrating stirring rod.

[0037] Wherein: 1, vibrator; 2, spray hole; 3, pipe head; 4, cement delivery pipe; 5, mortar pump; 6, vibrating stirring rod; 61, shell; 62, motor; 63, rotating shaft; 64, eccentric block; 65, stirring paddle. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0039] Please refer to Figs. 1-3 A method for reinforcing soft soil foundation is performed according to the following steps:

[0040] Step one: clean the construction area to make the surface of the soft soil flat, then arrange the pile position on the surface of the soft soil, and insert bamboo chip piles as markers on the pile position;

[0041] Step two: excavate a trench at the position of the bamboo chip pile, then install the vibrator 1 and adjust the position to ensure that the vibrator 1 is in a vertical state with the soft soil layer, the outer surface of the vibrator 1 is provided with a plurality of spray holes 2, the inside of the vibrator 1 is hollow, and the top of the vibrator 1 is connected with a pipe head 3;

[0042] Step three: connect the pipe head 3 with the cement delivery pipe 4, connect the cement delivery pipe 4 with the mortar pump 5, and use the mortar pump 5 to deliver cement mortar;

[0043] Step four: start the hole making operation, start the vibrator 1 to continuously penetrate into the deep layer of the soft soil until the hard soil layer is reached, in the process, the vibrator 1 extrudes the soft soil layer to make it dense, and a pile passage is formed in the soft soil;

[0044] Step five: after the bottom of the vibrator 1 reaches the hard soil layer, start to withdraw, in the process, the mortar pump 5 cooperates with the cement delivery pipe 4 and the pipe head 3 to pour the cement mortar into the inside of the vibrator 1, and then the cement mortar is sprayed out from the spray holes 2 into the pile passage;

[0045] Step six: after the vibrator 1 is completely withdrawn, add gravel from the top of the pile passage, and use a crane to insert the vibrating stirring rod 6 into the inside of the pile passage to stir and mix the cement and gravel;

[0046] Step seven: after the cement mixed with gravel in the pile passage and completely dried, compact the surface of the soft soil to complete the reinforcement of the soft soil foundation.

[0047] Specifically, the step one further includes geological survey and soil test on the soft soil, and the distance from the surface of the soft soil to the hard soil layer is obtained, and the interval of the pile position is 2-3m. The advantage is that the geological survey of the soft soil is needed before the pile position is arranged on the soft soil, so as to measure the depth and soil composition of the soft soil, so that the appropriate equipment is selected for the subsequent reinforcement operation, and the pile position is arranged at an interval of 2-3m, and the pile positions are arranged in an equilateral triangle, so that the pile positions are uniformly and densely distributed in the area to be constructed, and the reinforcement effect is good.

[0048] Specifically, the pore forming operation of the vibrator 1 is controlled at a speed of 0.5-2.0m / min in step four. The advantage is that the depth of the trench excavated in step two can bury the conical head of the vibrator 1 in the soft soil, and then start the vibrator 1 to generate vibration and continuously penetrate into the soft soil. The vibration process can compact the soft soil, so that the soft soil is compacted, thereby increasing the bearing capacity of the soft soil. The speed of pore forming is controlled between 0.5-2.0m / min, which ensures the efficiency and makes the soft soil fully vibrated and compacted until the vibrator 1 stops vibrating when it contacts the underground hard soil layer, so as to form a pile channel.

[0049] Specifically, the output end of the mortar pump 5 is connected to the cement delivery pipe 4, and the volume calculation formula of the cement mortar injected into the pile channel is:

[0050] v=π r 2 h×β

[0051] Wherein v is the injection amount of cement mortar, r is the radius of the pile channel, h is the height of the pile channel, and β is the mixing amount coefficient (i.e. the proportion of cement amount to the volume weight of the pile channel). The advantage is that the crane is used to withdraw the vibrator 1, and the mortar pump 5 is started to extract the cement mortar into the cement delivery pipe 4 during the withdrawal process. Then the cement mortar enters the inside of the vibrator 1, and with the increase of pressure, the cement mortar is sprayed from the spray hole 2 and splashes into the inside of the pile channel and the inner wall.

[0052] Specifically, the composition of the cement mortar is water, cement and sand, and the proportion of water, cement and sand is 2:2:1. The advantage is that the water, cement and sand are mixed in a ratio of 2:2:1 to make cement mortar, which ensures that the cement mortar has good flowability, is convenient for the cement mortar to be sprayed from the inside of the vibrator 1, and also has good strength after being mixed with sandstone, which plays a role in strengthening the soft soil foundation.

[0053] Specifically, the amount of sandstone added in step six is one third of the amount of cement mortar injected, and the diameter of the sandstone is 50-60mm. The advantage is that after the vibrator 1 is withdrawn from the pile channel, a forklift or other equipment is used to fill the sandstone into the pile channel, and the filling is performed several times. During the filling process, the vibrator 6 is used to mix the cement and sandstone.

[0054] Specifically, the vibrator 6 includes a housing 61, a motor 62, a rotating shaft 63, an eccentric block 64, and a stirring paddle 65. The motor 62 is installed in the housing 61, the output shaft of the motor 62 is connected to the rotating shaft 63 through a coupling, the eccentric block 64 is fixedly connected to the outer surface of the rotating shaft 63, and the stirring paddle 65 is fixedly connected to the bottom end of the rotating shaft 63. The advantage is that the motor 62 is started to drive the rotating shaft 63 to rotate, the rotating shaft 63 drives the eccentric block 64 to perform eccentric motion, the eccentric block 64 drives the housing 61 to vibrate, thereby accelerating the sinking of the sandstone into the bottom of the pile channel, and the vibration of the sandstone and the cement mortar promotes mixing. At the same time, the rotating shaft 63 drives the stirring paddle 65 to rotate to further improve the mixing efficiency of the cement mortar and the sandstone. During the stirring process, the soft soil on the inner wall of the pile channel can be driven to make the cement mortar, sandstone, and soft soil tightly combined. After the cement mixture in the pile channel is completely dried, a pile foundation is formed, which can greatly improve the strength and bearing capacity of the soft soil foundation.

[0055] Specifically, step seven also includes filling the top of the pile channel with filler, and the filler is concrete. The advantage is that after the cement mortar in the pile channel is completely dried, the trench excavated in step two, i.e., the top of the pile channel, needs to be filled with filler. The filler is concrete, and after the trench is completely filled with the filler and dried, the soft soil surface is compacted, which further improves the solidity of the soft soil.

[0056] Although embodiments of the present application have been shown and described, it is to be understood that various modifications, substitutions, replacements, and changes can be made to these embodiments without departing from the principles and spirit of the present application, and the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A method for reinforcing soft soil foundations, characterized in that: Follow these steps: Step 1: Clear the construction area to make the surface of the soft soil level, then set up the pile positions on the soft soil surface, and drive bamboo stakes into the pile positions as markers; Step 2: Excavate a trench at the location of the bamboo pile, then install the vibratory compactor (1) and adjust its position to ensure that the vibratory compactor (1) is perpendicular to the soft soil layer. Multiple spray holes (2) are opened on the outer surface of the vibratory compactor (1). The inside of the vibratory compactor (1) is hollow, and the top of the vibratory compactor (1) is connected to the pipe head (3). Step 3: Connect the pipe head (3) to the cement conveying pipe (4), and connect the cement conveying pipe (4) to the mortar pump (5), which is used to convey cement mortar; Step 4: Start the drilling operation and start the vibratory compactor (1) to continuously penetrate into the deep layer of soft soil until the hard soil layer is reached. During the process, the vibratory compactor (1) squeezes the soft soil layer to make it dense and forms a pile channel in the soft soil. Step 5: After the bottom of the vibratory compactor (1) reaches the hard soil layer, it begins to retract. During the process, the mortar pump (5) works with the cement delivery pipe (4) and the pipe head (3) to pump cement mortar into the vibratory compactor (1). Then the cement mortar is sprayed out from the nozzle (2) and enters the pile channel. Step 6: After the vibratory compactor (1) has completely retracted, add sand and gravel from the top of the pile channel, and use a crane to insert the vibratory mixing rod (6) into the pile channel to vibrate and mix the cement and sand and gravel; Step 7: After the cement-mixed sand and gravel in the pile channel has dried completely, compact the surface of the soft soil to complete the reinforcement of the soft soil foundation.

2. The method for reinforcing soft soil foundations according to claim 1, characterized in that: Step one also includes conducting geological surveys and soil tests on the soft soil to determine the distance between the soft soil surface and the hard soil layer, and setting the spacing of the pile positions to be 2-3m.

3. The method for reinforcing soft soil foundations according to claim 1, characterized in that: In step four, the drilling speed of the vibratory punch (1) is controlled at 0.5-2.0 m / min during the drilling operation.

4. The method for reinforcing soft soil foundations according to claim 1, characterized in that: The output end of the mortar pump (5) is connected to the cement conveying pipe (4), and the volume calculation formula of the cement mortar injection pile channel is as follows: v=π r 2 h×b Where v is the amount of cement mortar injected, r is the radius of the pile channel, h is the height of the pile channel, and β is the admixture coefficient.

5. The method for reinforcing soft soil foundations according to claim 1, characterized in that: The cement mortar is composed of water, cement, and sand, with a ratio of 2:2:

1.

6. The method for reinforcing soft soil foundations according to claim 1, characterized in that: In step six, the amount of sand and gravel added is one-third of the amount of cement mortar injected, and the diameter of the sand and gravel is 50-60mm.

7. The method for reinforcing soft soil foundations according to claim 1, characterized in that: The vibrating agitator (6) comprises a housing (61), a motor (62), a rotating shaft (63), an eccentric block (64), and an agitator (65). The motor (62) is installed inside the housing (61). The output shaft of the motor (62) is connected to the rotating shaft (63) via a coupling. The eccentric block (64) is fixedly connected to the outer surface of the rotating shaft (63). The agitator (65) is fixedly connected to the bottom end of the rotating shaft (63).

8. The method for reinforcing soft soil foundations according to claim 1, characterized in that: Step seven also includes filling the top of the pile channel with concrete.

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