CN105804107A - High-pressure-jetting and anti-seepage treatment method for triple tube of joint of underground diaphragm wall - Google Patents

Abstract

The invention discloses a three-layer pipe high-spraying anti-seepage treatment method for underground diaphragm wall joints. A group of high-pressure rotary grouting piles arranged in a staggered manner are used as the water isolation and reinforcement structure of the underground diaphragm wall joints. The joints of the underground diaphragm walls are determined first. position, use high-pressure rotary grouting piles to construct and reinforce the soil at the joints outside the foundation pit at the joint position, and carry out the construction of the underground diaphragm wall support system after the quality of the high-pressure rotary grouting pile group is stable. The purpose is to take advantage of the high-pressure rotary grouting piles' strong connection and large reinforcement range to strengthen the outer soil at the joint of the underground diaphragm wall, and enhance the integrity and water-proof and anti-seepage effect of the underground diaphragm wall. It takes full advantage of the characteristics of the underground diaphragm wall retaining structure and the triple tube high-pressure jet grouting pile, and is suitable for foundation pit support projects with small construction space and high anti-seepage requirements.

Description

A construction method for anti-seepage treatment of triple pipe high-spraying for joints of underground diaphragm walls

technical field

The invention relates to a construction method of a foundation pit support structure, in particular to a construction method for anti-seepage treatment of triple pipe high-spray pipes for joints of underground continuous walls.

Background technique

As a foundation pit enclosure structure, the underground diaphragm wall has structural integrity and anti-seepage effect as the key indicators to measure its engineering quality. During the construction process, the unremoved concrete flows around the joints of the underground wall, or due to joint grooves The verticality error of the section is too large, the joints are not cleaned properly, etc., and the joints of the underground diaphragm wall are prone to leakage. Therefore, ensuring the quality of joints and improving the anti-seepage effect of joints are the key points and difficulties in the construction of underground diaphragm walls. When joints are treated for anti-seepage, the grouting method is usually used to form a waterproof curtain outside the foundation pit, or the joints are reinforced by combining with bored piles or deep mixing piles.

In case of complex geological conditions, strata that are prone to water loss or leakage, or projects that require high waterproof quality, the traditional foundation treatment methods and single-pipe or double-pipe high-pressure rotary jet grouting can hardly meet the engineering requirements.

The triple tube high-pressure rotary spraying technology can efficiently fill and seal the pores and seepage spaces in the formation through the forced jet action, and connect the soil outside the pit and the underground continuous wall to form a solidified body with controllable properties, which can effectively Reinforce the soil outside the pit and play an anti-seepage effect.

Contents of the invention

In order to overcome the characteristics of the existing underground diaphragm wall joints that are difficult to prevent seepage and water, the present invention provides a three-layer pipe high-spray anti-seepage treatment method for underground diaphragm wall joints.

The present invention comprises the following steps:

1. After determining the hole position and reinforcement area of the triple-tube high-pressure rotary grouting pile, use a geological drilling rig to drill the pilot hole for the purpose of lowering the rotary nozzle tube used for rotary jet grouting into the pre-spinning stratum;

2. When the swirling nozzle is lowered to the pre-swirling depth, the swirling nozzle is lifted, and after the slurry spraying is completed, static pressure filling and grouting is carried out in the injection hole; finally, a high-pressure swirling pile is formed;

3. After the single pile of high-pressure rotary grouting piles is finished, move out of the hole position, and repeat the pile-making process of high-pressure rotary grouting piles after repositioning. Three high-pressure rotary grouting piles arranged in a quincunx shape form a group of high-pressure rotary grouting piles. Solid, complete the construction of a group of high-pressure jet grouting pile reinforcements on the outside of the underground diaphragm wall joint;

4. After a group of high-pressure rotary grouting pile reinforcement is completed, after the strength and quality of the high-pressure rotary grouting pile reinforcement are stable, the underground diaphragm wall guide wall, underground diaphragm wall body, underground diaphragm wall joint, and wall top crown beam are sequentially carried out. construction;

5. Each group of high-pressure rotary grouting pile reinforcements is located outside the underground diaphragm wall at the joint of the underground diaphragm wall. The outside of the underground diaphragm wall is the soil outside the foundation pit, and the inside of the underground diaphragm wall is the soil inside the foundation pit.

The diameter of the high-pressure rotary grouting pile is 800-1000 mm, and the reinforcement range of a group of high-pressure rotary grouting pile reinforcements is 1500 mm-2000 mm.

In the present invention, each group of high-pressure rotary grouting pile reinforcements is used as a water-proof and reinforcement structure for the underground diaphragm wall joint between two sections of the underground diaphragm wall.

Beneficial effects of the present invention:

The anti-seepage foundation pit support system formed by triple pipe high-pressure jet grouting piles outside the joints of the underground diaphragm wall can effectively reinforce the relatively weak parts of the original structure of the underground diaphragm wall, and the high-pressure jet grouting piles can further effectively play the role of Enhance the support effect of the underground diaphragm wall support system and the reliability of the water-stop curtain. The function of the support structure can be effectively and controllably reinforced, and the construction space can be effectively saved. The invention is suitable for the anti-seepage reinforcement of various forms of foundation pit support structures.

Description of drawings

Fig. 1 is a plan view of the waterproof reinforcement structure formed by the present invention.

Fig. 2 is a cross-sectional view of the waterproof reinforcement structure formed by the present invention.

1-Guide wall of underground diaphragm wall, 2-Crown beam on top of wall, 3-Wall body of underground diaphragm wall, 4-Soil body inside the foundation pit, 5-Soil body outside the foundation pit, 6-High pressure jet grouting pile reinforcement, 7- Diaphragm wall joints below ground.

detailed description

As shown in Figure 1 and Figure 2, the present invention comprises the following steps:

1. After determining the hole position and reinforcement area of the triple-tube high-pressure rotary grouting pile, use a geological drilling rig to drill the pilot hole for the purpose of lowering the rotary nozzle tube used for rotary jet grouting into the pre-spinning stratum;

2. When the swirling nozzle is lowered to the pre-swirling depth, the swirling nozzle is lifted, and after the slurry spraying is completed, static pressure filling and grouting is carried out in the injection hole; finally, a high-pressure swirling pile is formed;

3. After the single pile of high-pressure rotary grouting piles is finished, move out of the hole position, and repeat the pile-making process of high-pressure rotary grouting piles after repositioning. Three high-pressure rotary grouting piles arranged in a quincunx shape form a group of high-pressure rotary grouting piles. Solid 6, complete the construction of a group of high-pressure jet grouting pile reinforcement 6 on the outside of the underground diaphragm wall joint 7;

4. After the high-pressure rotary grouting pile reinforcement 6 is completed, after the strength and quality of the high-pressure rotary grouting pile reinforcement 6 are stable, the underground diaphragm wall guide wall 1, the underground diaphragm wall body 3, the underground diaphragm wall joint 7, and the top of the wall are sequentially carried out. Construction of crown beam 2;

5. Each group of high-pressure rotary grouting pile reinforcement 6 is located on the outside of the underground diaphragm wall 3 at the joint 7 of the underground diaphragm wall. The outer side of the underground diaphragm wall 3 is the soil 5 outside the foundation pit, and the inner side of the underground diaphragm wall 3 is The soil inside the foundation pit 4.

The diameter of the high-pressure jet grouting pile is 800-1000mm, and the reinforcement range of a group of high-pressure jet-jet pile reinforcements 6 is 1500mm-2000mm.

In the present invention, each group of high-pressure rotary grouting pile reinforcements 6 is used as a water-proof and reinforcement structure for the underground diaphragm wall joint 7 between two sections of the underground diaphragm wall.

Claims (2)

1. underground continuous wall connector triple tube preventing seepage with high-pressure sprayed concrete processes an engineering method, and the method comprises the following steps:

One, after determining position, hole and the reinforcing area of triple-pipe high pressure jet grouting stake, adopt geological drilling rig to bore guide hole, purpose by churning pipe used by rotary jet grouting down in the stratum prewhirled；

Two, when churning pipe is down to after the degree of depth of prewhirling, namely namely churning promotes churning pipe, at serosity AEI After End of Injection, carries out static pressure and fill grouting in spray-hole；Eventually form high-pressure rotary jet grouting pile；

Three, the churning of high-pressure rotary jet grouting pile single pile removes position, hole after completing, the stake process processed of high-pressure rotary jet grouting pile single pile is repeated after reorientating, the high-pressure rotary jet grouting pile of three interlaced plum blossom-shaped layouts constitutes one group of high-pressure rotary jet grouting pile reinforcing body (6), completes the construction of one group of high-pressure rotary jet grouting pile reinforcing body (6) in underground continuous wall connector (7) outside；

Four, after one group of high-pressure rotary jet grouting pile reinforcing body (6) completes, after high-pressure rotary jet grouting pile reinforcing body (6) intensity and steady quality, it is sequentially carried out the construction of guide wall of underground continuous wall (1), diaphram wall body of wall (3), underground continuous wall connector (7) and wall apical cap beam (2)；

Five, diaphram wall body of wall (3) outside at high-pressure rotary jet grouting pile reinforcing body (6) continuous wall connector located underground (7) place is often organized；

Often group high-pressure rotary jet grouting pile reinforcing body (6) is as the water proof of underground continuous wall connector (7) between two width sections of diaphram wall and ruggedized construction.

2. a kind of underground continuous wall connector triple tube preventing seepage with high-pressure sprayed concrete according to claim 1 processes engineering method, it is characterised in that: the diameter of described high-pressure rotary jet grouting pile is 800～1000mm.