CN102839691A - Quick sealing method and device for sandless cement pipe deep well dewatering wellhead - Google Patents

Abstract

The invention discloses a method and a device thereof for quickly sealing the head of a deep well dewatering with a sand-free cement pipe. A prefabricated steel sleeve is inserted into the sand-free cement pipe, and at least one water stop plate is arranged on the outer wall of the steel sleeve. Polyurethane sealant, SBS waterproof membrane and other materials are used for comprehensive waterproofing between the steel casing, sand-free cement pipe and the foundation concrete cushion. Dry hard concrete is poured inside the steel casing, and the upper part is sealed with a sealing plate, rubber waterproof pad and The flanges are connected together for one-time rapid plugging, which eliminates the problem of water seepage inside and outside the tube well after the well is sealed.

Description

Method and device for fast plugging wellhead of dewatering wellhead with sand-free cement pipe

technical field

The invention relates to the technical field of plugging of dewatering wells, in particular to a method and a device for quickly plugging the head of a dewatering well with a sand-free cement pipe.

Background technique

During the excavation of deep foundation pit dewatering wells in basements of high-rise buildings, underground garages and civil air defense projects, due to the penetration of groundwater in the soil, quicksand and springs often occur, and the soil at the bottom of the pit will continue to flow with the excavation. If the upwelling occurs, the slope will continue to collapse, which will not only affect the excavation construction of the earthwork, but also affect the safety of adjacent buildings, structures and foundation pit support structures, as well as the normal construction and construction of the foundation of the building. Engineering Quality.

At present, deep foundation pit dewatering wells usually use sand-free cement pipe deep wells for dewatering, which have been widely used in construction, railways, culverts and other fields. Deep foundation pit dewatering wells have the advantages of fast construction, large drainage, deep precipitation, and good drainage effect. Large well spacing and many other advantages.

When the current deep foundation pit dewatering well has a large area, due to the limitation of the depth of precipitation and the radius of influence of precipitation, the deep foundation pit dewatering well must be buried in the foundation pit, but at this time, the wellhead plugging has become a problem. The monopoly sealing method is often prone to leakage during the sealing process or after the sealing. The treatment is time-consuming and labor-intensive, and the sealing is not complete. Moreover, the conventional sealing method will cause cross-operation of types of work, which will affect The construction period and construction cost are high, and the sealing is more difficult, so it is difficult to guarantee the quality and effect of sealing.

Contents of the invention

In order to solve the above existing problems, the object of the present invention is to provide a quick plugging of the wellhead of deep well dewatering with sand-free cement pipe, which has simple process, fast construction speed, short cycle, will not affect the construction progress, and has a good one-time plugging effect. Method and apparatus used in the method.

In order to achieve the above object, the present invention adopts the following technical solutions:

The method for fast plugging the wellhead of deep well dewatering with sand-free cement pipe, the specific steps are as follows:

Step 1. Nozzle treatment: Lay the foundation concrete cushion to have a certain strength, and at the same time make the wellhead height of the sand-free cement pipe higher than the foundation concrete cushion;

Step 2. Manufacturing of steel casing: At least one water stop plate is welded on the outer wall of the circular steel casing, and a flange is welded on the top of the steel casing. Several screw holes are set on the flange, and corresponding Bolts, a sealing plate is set on the top of the steel casing, and a rubber waterproof pad is set between the sealing plate and the flange;

Step 3: Pre-insert and fix the steel casing: insert the steel casing into the sand-free cement pipe mouth before binding the steel bars on the foundation floor, and weld the steel support at the bottom of the water-stop plate closest to the sand-free cement pipe entrance to make the stop The water plate is higher than the wellhead of the sand-free cement pipe;

Step 4. Sealing and waterproofing of the interface: Fill waterproof sealing paste between the steel casing and the wellhead of the sand-free cement pipe. Fill and seal the wellhead of the sand-cement pipe, use cement mortar to make a circular arc corner at the junction of the sand-free cement pipe and the foundation concrete cushion, and make a waterproof layer on the arc corner, and the waterproof layer is connected to the lower water-stop plate , the interface is sealed with hot melt;

Step 5. Foundation construction: Bind the bottom row of steel bars of the foundation, disconnect at the wellhead of the sand-free cement pipe, set reinforcing ribs around it, pour concrete around the wellhead of the sand-free cement pipe, and place the upper part of the wellhead of the sand-free cement pipe with the wellhead as the center before pouring After the wellhead is quickly blocked, the expansive concrete grade higher than that of the surrounding concrete shall be used for supplementary pouring;

Step 6. Stop the precipitation at intervals in sequence: Stop the precipitation step by step for multiple sand-free cement pipe precipitation wells at intervals, and take out the water pump immediately after stopping the precipitation for a single well;

Step 7. Core filling and sealing: backfill the sand-free cement pipe with fine sand to the height of the concrete cushion, then put dry hard concrete mixed with early strength agent into the steel casing, vibrate and compact it, and pour it all the way to the steel casing Then place a rubber waterproof pad on the flange at the top of the steel casing, cover the sealing plate, fix the sealing plate on the flange with bolts, and pour expanded concrete on the top of the steel casing to make it It is equal to the concrete surface around the wellhead of the sandless cement pipe, vibrated and compacted, and covered and protected.

Preferably, the sealing paste in step 4 is polyurethane waterproof sealing paste.

Preferably, the waterproof layer in step 4 is made of SBS membrane waterproof layer.

A sand-free cement pipe deep well dewatering wellhead rapid plugging device, which includes a sand-free cement pipe and a steel casing, and the steel casing includes a steel pipe body, a flange, a sealing plate, bolts, a rubber waterproof pad, and at least one water-stop plate. The sand-free cement pipe is buried in the foundation concrete cushion, the bottom of the steel sleeve is inserted into the sand-free cement pipe, the flange is located on the top of the steel sleeve, the sealing plate is located above the flange, and the flange There are at least three screw holes on the sealing plate and the sealing plate. The rubber waterproof pad is located between the flange and the sealing plate. The flange and the sealing plate are firmly connected by bolts. on the outer wall.

Preferably, twelve screw holes are provided on the flange and the sealing plate.

Preferably, the outer wall of the steel casing is provided with two water-stopping plates, the upper water-stopping plate located in the middle of the steel casing, and the lower water-stopping plate located in the lower part of the steel casing.

Preferably, polyurethane waterproof sealant is filled between the steel casing and the wellhead of the sandless cement pipe.

Preferably, waterproof cement mortar is filled between the wellhead of the sand-free cement pipe and the lower water stop plate.

Preferably, the arc angle is made of cement mortar at the junction of the sand-free cement pipe and the foundation concrete cushion, and a waterproof layer is arranged on the arc angle, and the waterproof layer is connected with the lower water stop plate. Sealed with hot melt.

Preferably, the waterproof layer is an SBS membrane waterproof layer.

The advantages of the present invention are: a prefabricated steel casing is inserted into the sand-free cement pipe, at least one water-stop plate is arranged on the outer wall of the steel casing, and the steel casing, the sand-free cement pipe and the foundation concrete cushion Polyurethane sealant, SBS coil and other materials are used for comprehensive waterproofing in the room, and dry hard concrete is poured inside the steel casing, and the upper part is connected with a sealing plate, rubber waterproof pad and flange for one-time rapid sealing, eliminating The problem of water seepage inside and outside the tube well after sealing the well.

Description of drawings

Fig. 1 is the schematic flow sheet of method among the present invention;

Fig. 2 is a structural schematic diagram of the device in the present invention.

Among the figure 1, sandless cement pipe, 2, steel casing, 201, steel pipe body, 202, flange, 203, sealing plate, 204, bolt, 205, rubber waterproof pad, 206, upper water stop plate, 207, lower Waterproof board, 3. Waterproof sealing paste, 4. Waterproof cement mortar, 5. SBS membrane waterproof layer.

Detailed ways

The present invention will be described in further detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figures 1 to 2, the sand-free cement pipe deep well dewatering wellhead rapid plugging method, the whole process of the method is pipe mouth treatment - steel casing production - steel casing pre-inserted and fixed - interface sealing waterproof - foundation Construction - stop precipitation at intervals in sequence - fill and seal the core, the specific steps are:

Step 1, nozzle treatment: Lay the base concrete cushion to have a certain strength, and at the same time make the wellhead height of the sand-free cement pipe 1 higher than the foundation concrete cushion 220mm, the outer diameter of the sand-free cement pipe 1 used in this embodiment is 380mm , the inner diameter is 320mm;

Step 2, manufacture of steel casing 2: make circular steel casing 2 on the ground outside the pit, the outer diameter of steel casing 2 is 300mm, the wall thickness of steel casing 2 is 6.5mm, Two water-stop steel plates are welded on the outer wall, namely the upper water-stop plate 206 and the lower water-stop plate 207. The upper water-stop plate 206 is located at 1/2 of the height of the steel casing 2, and the lower water-stop plate 207 is located at 2. At 300mm from the lower end, the thickness of the water stop plate is 4mm and the width is 100mm. A flange 202 is welded on the top of the steel casing 2. The thickness of the flange 202 is 10mm and the width is 70mm. Set 12 screw holes on the flange 202 , configure 12 corresponding bolts 204, the diameter of the screw hole is 14mm, set a sealing plate 203 on the top of the steel casing 2, the thickness of the sealing plate 203 is 10mm, and set a rubber waterproof pad between the sealing plate 203 and the flange 202 205, the thickness of the rubber waterproof pad 205 is 6mm. ;

Step 3: Pre-insert and fix the steel sleeve 2: Insert the steel sleeve 2 into the sandless cement pipe 1 before binding the steel bars on the foundation floor, and weld the steel bar support at the bottom of the lower water stop plate 207 so that the lower water stop plate 207 is higher than Sand-free cement pipe 1 wellhead 80mm;

Step 4. Interface sealing and waterproofing: Fill waterproof sealant 3 between the steel casing 2 and the wellhead of the sand-free cement pipe 1. The waterproof sealant 3 in this embodiment adopts polyurethane waterproof sealant 3. After the waterproof sealant 3 is dried , use waterproof cement mortar 4 to fill and seal the 80 mm between the lower water stop plate 207 and the wellhead of the sand-free cement pipe 1, and use cement mortar to make an arc at the junction of the sand-free cement pipe 1 and the foundation concrete cushion, and the circle The radius of the arc corner is 5cm, and a SBS membrane waterproof layer 5 is made on the arc corner, and the SBS membrane waterproof layer 5 is always connected with the lower water stop plate 207, and the interface is sealed with hot melt;

Step 5. Foundation construction: Bind the bottom row of steel bars of the foundation, disconnect at the wellhead of the sand-free cement pipe 1, set reinforcing ribs around it, pour concrete around the wellhead of the sand-free cement pipe 1, and center the upper part of the wellhead of the sand-free cement pipe 1 The rear gate is left behind, and after the wellhead is quickly blocked, the expansive concrete that is one grade higher than the surrounding concrete is used for supplementary pouring;

Step 6. Stop the precipitation at intervals in sequence: stop the precipitation step by step for multiple sand-free cement pipe 1 precipitation wells at intervals, and take out the water pump immediately after stopping the precipitation of a single well, so that the adverse effects of the backwater pressure can be reduced to the greatest effect. At the same time, it can also ensure the effect of sealing the well and stopping water;

Step 7. Fill the core and seal: backfill the sand-free cement pipe 1 with fine sand to the height of the concrete cushion, then put dry hard concrete mixed with early strength agent into the steel casing 2, vibrate and compact, and pour until At the top of the steel casing 2, place a rubber waterproof gasket 205 on the flange 202 at the top of the steel casing 2, cover the sealing plate 203, and fix the sealing plate 203 on the flange 202 with 12 bolts 204, and the tightening force The spacing is 50N.m-60N.m, and then the top of the steel casing 2 is poured with expansive concrete, so that the inside of the reinforcement is equal to the outside of the reinforcement.

After the construction is completed, the waterproof layer, the steel casing and the joint of the sand-free cement pipe, the water stop board, the sealing board and other parts should be inspected and qualified before the next step of construction can be carried out.

The device used in the sand-free cement pipe deep well dewatering wellhead rapid plugging method of the present invention is a sand-free cement pipe deep well dewatering wellhead rapid plugging device, which includes a sand-free cement pipe 1 and a steel casing 2, a steel casing Including steel pipe body 201, flange 201, sealing plate 203, bolts 204, rubber waterproof pad 205 and two water-stop plates, wherein the sand-free cement pipe 1 is buried in the foundation concrete cushion, and the bottom of the steel casing 2 is inserted into a sand-free In the cement pipe 1, polyurethane waterproof sealant 3 is filled between the steel casing 2 and the wellhead of the sandless cement pipe 1. The flange 202 is located on the top of the steel casing 2, and the sealing plate 203 is located above the flange 202. 202 and the sealing plate 203 are provided with twelve screw holes, a rubber waterproof gasket 205 is provided between the flange 202 and the sealing plate 203, and the flange 202 and the sealing plate 203 are firmly connected by bolts 204, and the water stop plate is located at On the outer wall of the steel casing 2, the number of water-stopping plates can be determined according to the height of the steel casing. In this embodiment, there are two water-stopping plates, and the upper water-stopping plate 206 is located in the middle of the steel casing 2. , the lower water-stop plate 207 is located at the lower part of the steel casing 2, and the waterproof cement mortar 4 is filled between the wellhead of the sand-free cement pipe 1 and the lower water-stop plate 207, and is used at the junction of the sand-free cement pipe 1 and the foundation concrete cushion The cement mortar is made into an arc angle, and an SBS coiled material waterproof layer 5 is arranged on the arc angle, and the SBS coiled material waterproof layer 5 is connected with the lower water stop plate 207, and the interface is sealed with hot melt.

The above description is only a preferred embodiment of the present invention. It should be pointed out that those skilled in the art can also make some similar deformations and improvements without departing from the creative concept of the present invention. Within the protection scope of the present invention.

Claims (10)

1. The method for rapid plugging of the wellhead of deep well dewatering with sand-free cement pipe, characterized in that the specific steps are: Step 1. Nozzle treatment: Lay the foundation concrete cushion to have a certain strength, and at the same time make the wellhead height of the sand-free cement pipe higher than the foundation concrete cushion; Step 2. Manufacturing of steel casing: At least one water stop plate is welded on the outer wall of the circular steel casing, and a flange is welded on the top of the steel casing. Several screw holes are set on the flange, and corresponding Bolts, a sealing plate is set on the top of the steel casing, and a rubber waterproof pad is set between the sealing plate and the flange; Step 3: Pre-insert and fix the steel casing: insert the steel casing into the sand-free cement pipe mouth before binding the steel bars on the foundation floor, and weld the steel support at the bottom of the water-stop plate closest to the sand-free cement pipe entrance to make the stop The water plate is higher than the wellhead of the sand-free cement pipe; Step 4. Sealing and waterproofing of the interface: Fill waterproof sealing paste between the steel casing and the wellhead of the sand-free cement pipe. Fill and seal the wellhead of the sand-cement pipe, use cement mortar to make a circular arc corner at the junction of the sand-free cement pipe and the foundation concrete cushion, and make a waterproof layer on the arc corner, and the waterproof layer is connected to the lower water-stop plate , the interface is sealed with hot melt; Step 5. Foundation construction: Bind the bottom row of steel bars of the foundation, disconnect at the wellhead of the sand-free cement pipe, set reinforcing ribs around it, pour concrete around the wellhead of the sand-free cement pipe, and place the upper part of the wellhead of the sand-free cement pipe with the wellhead as the center before pouring After the wellhead is quickly blocked, the expansive concrete grade higher than that of the surrounding concrete shall be used for supplementary pouring; Step 6. Stop the precipitation at intervals in sequence: Stop the precipitation step by step for multiple sand-free cement pipe precipitation wells at intervals, and take out the water pump immediately after stopping the precipitation for a single well; Step 7. Core filling and sealing: backfill the sand-free cement pipe with fine sand to the height of the concrete cushion, then put dry hard concrete mixed with early strength agent into the steel casing, vibrate and compact it, and pour it all the way to the steel casing Then place a rubber waterproof pad on the flange at the top of the steel casing, cover the sealing plate, fix the sealing plate on the flange with bolts, and pour expanded concrete on the top of the steel casing to make it It is equal to the concrete surface around the wellhead of the sandless cement pipe, vibrated and compacted, and covered and protected. 2. The method for quickly plugging the wellhead of a deep well with sand-free cement pipe according to claim 1, wherein the waterproof sealant in the step 4 is polyurethane waterproof sealant. 3. The method for quick plugging of sand-free cement pipe deep well dewatering wellhead according to claim 1, characterized in that, the waterproof layer in the step 4 adopts SBS coiled material waterproof layer. 4. The sandless cement pipe deep well dewatering wellhead rapid plugging device is characterized in that it includes a sandless cement pipe and a steel casing, and the steel casing includes a steel pipe body, a flange, a sealing plate, a bolt, a rubber waterproof pad and at least one The water stop plate, the sand-free cement pipe is buried in the foundation concrete cushion, the bottom of the steel sleeve is inserted into the sand-free cement pipe, the flange is located on the top of the steel sleeve, and the sealing plate is located on the flange Above, the flange and the sealing plate are provided with at least three screw holes, the rubber waterproof pad is located between the flange and the sealing plate, the flange and the sealing plate are firmly connected by bolts, the stop The water plate is located on the outer wall of the steel casing. 5. The sand-free cement pipe deep well dewatering wellhead rapid plugging device according to claim 4, characterized in that the flange and the sealing plate are each provided with twelve screw holes. 6. The sand-free cement pipe deep well dewatering wellhead rapid plugging device according to claim 5, characterized in that, the outer wall of the steel casing is provided with two water stop plates, and the one located in the middle of the steel casing is the upper The water stop plate is located at the lower part of the steel casing as the lower water stop plate. 7. The sand-free cement pipe deep well dewatering wellhead rapid plugging device according to claim 6, characterized in that polyurethane waterproof sealant is filled between the steel casing and the sand-free cement pipe wellhead. 8. The sand-free cement tube deep well dewatering wellhead rapid plugging device according to claim 7, characterized in that waterproof cement mortar is filled between the sand-free cement tube wellhead and the lower water stop plate. 9. The sandless cement pipe deep well dewatering wellhead rapid plugging device according to claim 8, characterized in that, the arc angle is made with cement mortar at the junction of the sandless cement pipe and the foundation concrete cushion, There is a waterproof layer on the arc corner, the waterproof layer is connected with the lower water stop plate, and the interface is sealed by hot melt. 10. The sand-free cement pipe deep well dewatering wellhead rapid plugging device according to claim 9, characterized in that the waterproof layer is an SBS membrane waterproof layer.

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