阅读说明：本技术 一种可注浆式双壁承压降水管井装置及其施工方法 (Groutable double-wall pressure-bearing and pressure-reducing water pipe well device and construction method thereof ) 是由 汤友生 孙海明 陈磊 代兴云 俞骁倩 于 2021-08-06 设计创作，主要内容包括：本发明提供一种可注浆式双壁承压降水管井装置及其施工方法,结构设计合理、可靠性高、能适用不同深基坑承压水降水要求。外井管包括钢管和滤管,滤管和钢管均固定在降水井孔中,滤管位于钢管下方,钢管设置于降水井孔的承压隔水层处,滤管设置于降水井孔的承压含水层处,内井管固定设置在钢管内；填料层填充在外井管管壁与降水井孔孔壁之间；注浆喷嘴设置在钢管和内井管之间；喷嘴、可伸缩喷嘴管、注浆管依次连接；喷嘴和可伸缩喷嘴管活动安装在限位管内,所述的钢管上开设有注浆孔,喷嘴对准注浆孔；橡胶膜覆盖在注浆孔上；限位管固定设置在钢管和内井管之间；抽水泵设置于降水井孔的底部,出水管与抽水泵连接。(The invention provides a groutable double-wall pressure-bearing and pressure-reducing water pipe well device and a construction method thereof, which have reasonable structural design and high reliability and can meet the requirements of different deep foundation pit confined water and water precipitation. The outer well pipe comprises a steel pipe and a filter pipe, the filter pipe and the steel pipe are fixed in the precipitation well hole, the filter pipe is positioned below the steel pipe, the steel pipe is arranged at a confined water-stop layer of the precipitation well hole, the filter pipe is arranged at the confined water-stop layer of the precipitation well hole, and the inner well pipe is fixedly arranged in the steel pipe; the packing layer is filled between the pipe wall of the outer well pipe and the wall of the dewatering well hole; the grouting nozzle is arranged between the steel pipe and the inner well pipe; the nozzle, the telescopic nozzle pipe and the grouting pipe are connected in sequence; the nozzle and the telescopic nozzle pipe are movably arranged in the limiting pipe, the steel pipe is provided with a grouting hole, and the nozzle is aligned to the grouting hole; the rubber film covers the grouting hole; the limiting pipe is fixedly arranged between the steel pipe and the inner well pipe; the water suction pump is arranged at the bottom of the precipitation well hole, and the water outlet pipe is connected with the water suction pump.)

1. A groutable double-wall pressure-bearing downcomer well device comprises a dewatering well hole and is characterized in that: the device also comprises an outer well pipe, an inner well pipe, a grouting nozzle, a packing layer, a water pump and a water outlet pipe; the outer well pipe comprises a steel pipe and a filter pipe, the filter pipe and the steel pipe are both fixed in the precipitation well hole, the filter pipe is positioned below the steel pipe, the steel pipe is arranged at a confined water-stop layer of the precipitation well hole, the filter pipe is arranged at a confined water-stop layer of the precipitation well hole, and the inner well pipe is fixedly arranged in the steel pipe; the packing layer is filled between the pipe wall of the outer well pipe and the wall of the dewatering well hole; the grouting nozzle is arranged between the steel pipe and the inner well pipe and comprises a nozzle, a rubber film, a telescopic nozzle pipe and a limiting pipe; the nozzle, the telescopic nozzle pipe and the grouting pipe are connected in sequence; the nozzle and the telescopic nozzle pipe are movably arranged in the limiting pipe, the steel pipe is provided with a grouting hole, and the nozzle is aligned to the grouting hole; the rubber film covers the grouting hole; the limiting pipe is fixedly arranged between the steel pipe and the inner well pipe; the water suction pump is arranged at the bottom of the precipitation well hole, and the water outlet pipe is connected with the water suction pump.

2. The groutable double-walled pressure-bearing downcomer well device of claim 1, characterized in that: the packing layer comprises a clay layer, a clay ball layer and a sand gravel layer, wherein the sand gravel layer, the clay ball layer and the clay layer are sequentially arranged from bottom to top; the gravel layer is filled outside the pressure-bearing water-containing layer; the clay ball layer is filled outside the pressure-bearing water-resisting layer; the clay layer is filled at a position close to the ground.

3. The groutable double-walled pressure-bearing downcomer well device of claim 1, characterized in that: the grouting nozzle further comprises a fixing support, and the limiting pipe, the steel pipe and the inner well pipe are fixed together by the fixing support.

4. The groutable double-walled pressure-bearing downcomer well device of claim 1, characterized in that: the telescopic nozzle pipe is a rubber pipe or a threaded telescopic pipe.

5. The groutable double-walled pressure-bearing downcomer well device of claim 1, characterized in that: the plurality of grouting nozzles 5 are arranged in sequence along the height direction and the circumferential direction of the outer well pipe 2.

6. A method of constructing a groutable double-walled pressure-bearing and drawdown piping well assembly as claimed in any one of claims 1 to 5, wherein: the method comprises the following steps:

the first step is as follows: performing dewatering well hole construction by using related drilling equipment;

the second step is that: a grouting pipe and a grouting nozzle are arranged between the outer well pipe and the inner well pipe;

the third step: sinking the grouting nozzle and the grouting pipe to a specified elevation along with the outer well pipe and the inner well pipe;

the fourth step: after the outer well pipe, the inner well pipe, the grouting pipe and the grouting nozzle are sunk, the packing layer between the outer well pipe and the dewatering well hole is backfilled according to requirements;

the fifth step: after the packing layer is backfilled, performing pressurized grouting by using a grouting pipe, and extending a telescopic nozzle pipe under the action of grouting pressure to ensure that a nozzle pierces a rubber membrane, extends between an outer well pipe and a precipitation well hole to perform grouting and plugs a gap of the packing layer near the nozzle;

and a sixth step: after the filling layer gap grouting plugging is finished, the confined water is pumped and discharged by using a water pump and a water pumping pipe, and the height of a water head of the confined aquifer is reduced.

7. The construction method according to claim 6, wherein: the guniting material adopts water glass or cement paste.

Technical Field

The invention relates to a groutable double-wall pressure-bearing and pressure-reducing water pipe well device and a construction method thereof, and relates to the field of civil and architectural engineering.

Background

At present, in the design and construction process of a deep foundation pit, the success or failure of underground water control becomes the key of whether the foundation pit can be safely and smoothly constructed, particularly confined water, and the surge of the confined water brings huge property loss and casualties to engineering construction. At present, reducing the confined water head becomes the most direct and common way to deal with the risk of confined water gushing besides separating the hydraulic connection between the confined aquifer and the foundation pit. However, because the pressure of the confined water is high, the construction requirement of the confined pressure-reducing water pipe well is high, a gap between the confined pressure-reducing water pipe well and the soil body is often a weak area where the confined water suddenly flows, and the life safety of construction operators is directly threatened when the confined water carrying silt suddenly flows into the foundation pit along the weak area. Therefore, on the premise of ensuring the functions of the pressure-bearing downcomer well, improvement and optimization of the pressure-bearing downcomer well are needed.

Disclosure of Invention

The invention aims to overcome the defects in the prior art and provide the grouting type double-wall pressure bearing and reducing water pipe well device which is reasonable in structural design, high in reliability and capable of meeting different requirements of deep foundation pit confined water and water precipitation and the construction method thereof.

The technical scheme adopted by the invention for solving the problems is as follows: a groutable double-wall pressure-bearing downcomer well device comprises a dewatering well hole and is characterized in that: the device also comprises an outer well pipe, an inner well pipe, a grouting nozzle, a packing layer, a water pump and a water outlet pipe; the outer well pipe comprises a steel pipe and a filter pipe, the filter pipe and the steel pipe are both fixed in the precipitation well hole, the filter pipe is positioned below the steel pipe, the steel pipe is arranged at a confined water-stop layer of the precipitation well hole, the filter pipe is arranged at a confined water-stop layer of the precipitation well hole, and the inner well pipe is fixedly arranged in the steel pipe; the packing layer is filled between the pipe wall of the outer well pipe and the wall of the dewatering well hole; the grouting nozzle is arranged between the steel pipe and the inner well pipe and comprises a nozzle, a rubber film, a telescopic nozzle pipe and a limiting pipe; the nozzle, the telescopic nozzle pipe and the grouting pipe are connected in sequence; the nozzle and the telescopic nozzle pipe are movably arranged in the limiting pipe, the steel pipe is provided with a grouting hole, and the nozzle is aligned to the grouting hole; the rubber film covers the grouting hole; the limiting pipe is fixedly arranged between the steel pipe and the inner well pipe; the water suction pump is arranged at the bottom of the precipitation well hole, and the water outlet pipe is connected with the water suction pump.

The packing layer comprises a clay layer, a clay ball layer and a sand gravel layer, wherein the sand gravel layer, the clay ball layer and the clay layer are sequentially arranged from bottom to top; the gravel layer is filled outside the pressure-bearing water-containing layer; the clay ball layer is filled outside the pressure-bearing water-resisting layer; the clay layer is filled at a position close to the ground.

The grouting nozzle also comprises a fixing support, and the fixing support fixes the limiting pipe, the steel pipe and the inner well pipe together.

The telescopic nozzle pipe adopts a rubber pipe or a threaded telescopic pipe.

The plurality of grouting nozzles 5 are arranged in sequence along the height direction and the circumferential direction of the outer well pipe 2.

A construction method of a groutable double-wall pressure-bearing and pressure-reducing water pipe well device is characterized in that: the method comprises the following steps:

the first step is as follows: performing dewatering well hole construction by using related drilling equipment;

the second step is that: a grouting pipe and a grouting nozzle are arranged between the outer well pipe and the inner well pipe;

the third step: sinking the grouting nozzle and the grouting pipe to a specified elevation along with the outer well pipe and the inner well pipe;

the fourth step: after the outer well pipe, the inner well pipe, the grouting pipe and the grouting nozzle are sunk, the packing layer between the outer well pipe and the dewatering well hole is backfilled according to requirements;

the fifth step: after the packing layer is backfilled, performing pressurized grouting by using a grouting pipe, and extending a telescopic nozzle pipe under the action of grouting pressure to ensure that a nozzle pierces a rubber membrane, extends between an outer well pipe and a precipitation well hole to perform grouting and plugs a gap of the packing layer near the nozzle;

and a sixth step: after the filling layer gap grouting plugging is finished, the confined water is pumped and discharged by using a water pump and a water pumping pipe, and the height of a water head of the confined aquifer is reduced.

The guniting material adopts water glass or cement paste.

Compared with the prior art, the invention has the following advantages and effects:

1. the dewatering function of the pressure-bearing dewatering well is not changed, and the grouting facility is arranged in the pipe well, so that the plugging performance of the external filler of the pipe well is enhanced, and the safety of the pipe well in the dewatering process is ensured.

2. The double-wall steel pipe with the combination of the outer well pipe and the inner well pipe is adopted, the rigidity and the integrity of the pipe well are improved, the reliability of the grouting pipe in the using process is enhanced, and meanwhile, the influence on pumping and drainage caused by the grouting process is avoided.

3. The grouting holes are wrapped by rubber membranes, telescopic nozzle pipes are adopted, the nozzles can be stretched under the action of grouting pressure, the rubber membranes are punctured, the nozzles extend to positions between the outer well pipe and the precipitation well hole to spray, the nozzles can be well protected in the process, and the nozzles are prevented from being damaged in the process of sinking the well pipe.

4. The grouting nozzle can preset different grouting directions according to different requirements, and can be provided with a plurality of grouting devices at different elevations, so that the effectiveness of plugging and sealing of the joint filling is ensured.

Drawings

Fig. 1 is a schematic structural diagram of an embodiment of the present invention.

Fig. 2 is a schematic cross-sectional view of an embodiment of the present invention.

Fig. 3 is a schematic structural diagram of a grouting nozzle before grouting in the embodiment of the invention.

Fig. 4 is a schematic structural diagram of a post-grouting injection nozzle in the embodiment of the invention.

Detailed Description

The present invention will be described in further detail below by way of examples with reference to the accompanying drawings, which are illustrative of the present invention and are not to be construed as limiting the present invention.

The water-saving well comprises a precipitation well hole 1, an outer well pipe 2, an inner well pipe 3, a grouting pipe 4, a grouting nozzle 5, a packing layer 6, a water pump 7 and a water outlet pipe 8, wherein the outer well pipe 2 comprises a steel pipe 2.1 and a filter pipe 2.2.

The precipitation well 1 is worked in the foundation pit with the associated drilling equipment as required. After construction is finished, determining the distribution conditions of a confined aquifer and a confined aquifer in the actual dewatering well hole 1 according to geological drilling data, and lofting the lengths of materials such as well pipes according to the distribution conditions of the actual confined aquifer and the confined aquifer; a grouting pipe 4 and a grouting nozzle 5 are arranged between the outer well pipe 2 and the inner well pipe 3, and the grouting pipe 4 is connected with the grouting nozzle 5.

After the material preparation is finished, sequentially sinking the filter tube 2.2, the steel tube 2.1, the inner well tube 3 and the grouting nozzle 5 in sections, connecting the grouting tube 4 section by section, sinking to a designated elevation, fixing the filter tube 2.2 and the steel tube 2.1 in the precipitation well hole 1, positioning the filter tube 2.2 below the steel tube 2.1, arranging the steel tube 2.1 at a pressure-bearing water-resisting layer, arranging the filter tube 2.2 at a pressure-bearing water-resisting layer, and fixing the inner well tube 3 in the steel tube 2.1. The grouting pipe 4 is positioned between the outer well pipe 2 and the inner well pipe 3 and is communicated up and down.

After the filter pipe 2.2, the steel pipe 2.1, the inner well pipe 3, the grouting nozzle 5, the grouting pipe 4 and the like are installed and sunk, a packing layer 6 between the pipe wall of the outer well pipe 2 and the hole wall of the precipitation well hole 1 is backfilled according to requirements, wherein the packing layer 6 comprises a clay layer 6.1, a clay ball layer 6.2 and a sand gravel layer 6.3, and the sand gravel layer 6.3, the clay ball layer 6.2 and the clay layer 6.1 are backfilled from bottom to top in sequence. The gravel layer 6.3 is a well pipe filter layer and is filled outside the pressure-bearing water-containing layer; the clay ball layer 6.2 is a plugging layer outside the well pipe and is filled outside the pressure-bearing water-proof layer; the clay layer 6.1 is arranged close to the ground to avoid surface water infiltration. The fillers are required to be backfilled and compacted respectively.

The water suction pump 7 is arranged at the bottom of the precipitation well hole 1, and the water outlet pipe 8 is connected with the water suction pump 7.

After the packing layer 6 is backfilled, grouting between the outer well pipe 2 and the precipitation well hole 1 through a grouting nozzle 5 by using a grouting pipe 4 between the outer well pipe 2 and the inner well pipe 3, and reinforcing and plugging gaps of the packing layer 6; after the grouting plugging of the gaps of the packing layer 6 is finished and the required strength is achieved, the confined water is pumped and discharged by using the water suction pump 7 and the water outlet pipe 8, so that the height of the water head of the confined aquifer is reduced.

The outer well pipe 2 and the inner well pipe 3 are fixed with each other by customization or on-site processing of manufacturers and are divided into small sections with different lengths, the different sections can be connected up and down, the grouting nozzle 5 and the grouting pipe 4 are positioned between the outer well pipe 2 and the inner well pipe 3, and the grouting pipe 4 can be connected up and down.

The grouting nozzle 5 comprises a nozzle 5.1, a rubber film 5.2, a telescopic nozzle pipe 5.3, a limiting pipe 5.4 and a fixing support 5.5.

The nozzle 5.1, the telescopic nozzle pipe 5.3 and the grouting pipe 4 are connected in sequence; the nozzle 5.1 and the telescopic nozzle pipe 5.3 are movably arranged in the limiting pipe 5.4, and the nozzle 5.1 and the telescopic nozzle pipe 5.3 can move along the limiting pipe 5.4; the steel pipe 2.1 is provided with a grouting hole, and the nozzle 5.1 is aligned with the grouting hole; the rubber film 5.2 covers the grouting hole; the fixed support 5.5 fixes the limiting pipe 5.4, the steel pipe 2.1 and the inner well pipe 3 together. And pressurized grouting is carried out through the grouting pipe 4, under the action of grouting pressure, the telescopic nozzle pipe 5.3 extends, so that the nozzle 5.1 pierces the rubber membrane 5.2, extends to a position between the outer well pipe 2 and the precipitation well hole 1 for grouting, and a gap of a clay ball layer 6.2 near the nozzle 5.1 is plugged. The telescopic nozzle pipe 5.3 adopts a rubber pipe or a threaded telescopic pipe, and can be stretched under the pushing action of pressure. A plurality of grouting nozzles 5 are sequentially arranged along the height direction and the circumferential direction of the outer well pipe 2; grouting nozzle 5 can utilize spacing pipe to carry out the direction according to actual conditions and adjust, can set up the grouting nozzle 5 of a plurality of directions to guarantee whitewashing scope and effect. According to actual conditions, a plurality of grouting nozzles 5 can be arranged at different depths, and even all well pipes except a confined aquifer can be subjected to grouting and joint filling if necessary.

The embodiment also provides a construction method of the groutable double-wall pressure-bearing and pressure-reducing water pipe well device, which comprises the following steps:

the first step is as follows: carrying out precipitation well hole 1 construction by using related drilling equipment as required;

the second step is that: setting out the length of the well pipe according to the distribution conditions of an actual confined aquifer and a confined water-barrier in the precipitation well hole 1, and particularly installing a grouting pipe 4 and a grouting nozzle 5 between an outer well pipe 2 and an inner well pipe 3;

the third step: the outer well pipe 2 and the inner well pipe 3 sink in sections, the grouting nozzle 5 and the grouting pipe 4 sink to a specified elevation along with the outer well pipe 2 and the inner well pipe 3 together in sections according to design requirements, and when sinking, firm connection between the upper section and the lower section of the grouting pipe 4 needs to be ensured.

The fourth step: after the outer well pipe 2, the inner well pipe 3, the grouting pipe 4 and the like are sunk, the packing layer 6 between the outer well pipe 2 and the precipitation well hole 1 is backfilled according to requirements, and the sand gravel layer 6.3, the clay ball layer 6.2 and the clay layer 6.1 are backfilled from bottom to top in sequence. The fillers are required to be backfilled and compacted according to requirements.

The fifth step: after the packing layer 6 is backfilled, the grouting pipe 4 is used for pressurizing and grouting, under the action of grouting pressure, the telescopic nozzle pipe 5.3 extends, so that the nozzle 5.1 pierces the rubber membrane 5.2, extends to a position between the outer well pipe 2 and the precipitation well hole 1 for grouting, and a gap of the packing layer 6 near the nozzle 5.1 is plugged. The guniting material can adopt sealing grout with quick hardening and low permeability such as water glass, cement paste and the like according to actual conditions.

And a sixth step: after the grouting and plugging of the gaps of the packing layer 6 are finished, the water pump 7 and the water pumping pipe 8 are utilized to pump and discharge confined water, and the height of a water head of the confined aquifer is reduced.

In addition, it should be noted that the specific embodiments described in the present specification may be different in the components, the shapes of the components, the names of the components, and the like, and the above description is only an illustration of the structure of the present invention. Equivalent or simple changes in the structure, characteristics and principles of the invention are included in the protection scope of the patent. Various modifications, additions and substitutions for the specific embodiments described may be made by those skilled in the art without departing from the scope of the invention as defined in the accompanying claims.