CN206512759U - A kind of ground-connecting-wall G type joints of pre-buried repeatable Grouting Pipe - Google Patents

Abstract

The utility model discloses a ground connection wall G-shaped joint for pre-buried repeatable grouting pipes, which is characterized in that it comprises a first-stage groove cross-shaped steel plate (1) and a second-stage groove U-shaped steel plate (2). The first-stage groove cross-shaped steel plate (1) and the second-stage groove U-shaped steel plate (2) are pre-installed in the reinforcement cage (3) and are located between two adjacent concrete connecting walls; A sealing steel plate (6) is provided on the concrete between the cross-shaped steel plate (1) and the second-stage groove U-shaped steel plate (2); between the flange plate (2.1) and the U-shaped steel plate (2.2) A grouting pipe (7) is installed in the transition section between them; it overcomes the shortcomings of serious water leakage at the ground-to-wall joints used in the prior art, has good water-stop effect, low engineering cost, and easy inspection and judgment of construction quality , The advantages of simple construction technology.

Description

A G-type joint of ground wall with pre-embedded repeatable grouting pipe

technical field

The utility model relates to the technical fields of subway engineering and construction engineering, and more specifically relates to a G-shaped joint of ground connecting walls with pre-embedded repeatable grouting pipes.

Background technique

With the rapid development of underground engineering, the design and construction of ultra-deep foundation pits under various complex geological and environmental conditions has become a new normal. Due to its outstanding characteristics of high rigidity, good waterproof effect, mature construction technology, and low construction difficulty, the underground diaphragm wall has gradually become the preferred structural type for deep foundation pit enclosure schemes under complex geological conditions.

At present, I-steel joints are more commonly used for water-stopping joints of ground and wall joints in deep foundation pits of subway stations, and a few cross-steel joints are used.

In the process of excavating ultra-deep foundation pits in highly confined water-bearing strata, water gushing and sand gushing in the joints of ground connection walls often occur, which has a great impact on engineering construction and the surrounding environment, and often has huge economic losses and social impacts. For example, in the construction of a three-storey underground subway station (the depth of the foundation pit is generally 24-30m) in the first-level terrace area of the Yangtze River in Wuhan City, due to the poor construction quality of the ground connection wall joints, water leakage and sand leakage are very likely to occur under high pressure water heads, which is dangerous. Occurs from time to time, becoming a major safety issue that plagues subway construction.

In order to strengthen the water-stopping effect of the joints of the ground-connecting wall, it is generally adopted to increase the water-stopping of high-pressure rotary jetting piles at the outer joints of the ground-connecting wall, or to install a continuous water-stop curtain (such as three-axis mixing piles, plain ground connecting walls, etc.), which greatly increases the Engineering investment. However, due to the limitations of the current construction technology and construction level, the construction quality of high-pressure jet grouting piles or three-axis mixing piles below 20m below the ground is difficult to guarantee, and it cannot solve the problem of water leakage at the joints of the ground connection wall. Although the anti-seepage effect is better, the project investment cost is high.

Contents of the invention

The purpose of the utility model is to overcome the disadvantages of the above-mentioned background technology, and propose a G-type joint of the ground connection wall with pre-embedded repeatable grouting pipes.

The purpose technical solution of the utility model is implemented through the following measures: a G-type joint of the ground connection wall with a pre-embedded repeatable grouting pipe, which includes a cross-shaped steel plate in the first-stage groove and a U-shaped steel plate in the second-stage groove. The cross-shaped steel plate of the first-stage groove and the U-shaped steel plate of the second-stage groove are pre-installed in the reinforcement cage and are located between two adjacent concrete walls; The excavation side sealing steel plate between them; the U steel plate of the second-stage groove is located on one side of the cross-shaped steel plate of the first-stage groove, and the cross-shaped steel plate of the first-stage groove includes a transverse steel plate and a vertical steel plate, and the The U-shaped steel plate of the second-stage groove includes flange plates and U-shaped steel plates at both ends, and a grouting pipe is installed at the transition section between the flange plate and the U-shaped steel plate; one end of the transverse steel plate extends Entering into the notch of the U-shaped steel plate, concrete diversion holes are arranged at equal intervals on the transverse steel plate and the U-shaped steel plate; anti-slip iron sheets are arranged on the inner and outer sides of the steel cage.

In the above technical solution: the distance between the vertical steel plate and the flange plate is 10-15 cm.

In the above technical solution: the distance between the vertical steel plate and the flange plate is 15 cm.

In the above technical scheme: the vertical steel plate and the flange plate both protrude from the pit face of the reinforcement cage by 5 cm each.

In the above technical solution: the thickness of the grout stop iron sheet is 0.5 mm.

The utility model also proposes a construction method: a method for pre-embedding the G-type joint of the ground connection wall of the repeatable grouting pipe, including the following steps;

①. According to the quality inspection of joint construction, including segmental water pressure test or cross-hole acoustic wave test, segmental high-pressure grouting from bottom to top;

②. Bind the reinforcement cage according to the requirements of the design drawings, and install the cross-shaped steel plate in the first-stage groove and the U-shaped steel plate in the second-stage groove in the reinforcement cage; pour the reinforcement cage on one side of the cross-shaped steel plate in the first-stage groove first;

③. When constructing the U-shaped steel plate of the second-stage groove, clean the residual sandbags and concrete agglomerates on the side of the cross-shaped steel plate of the first-stage groove, and pour the cross-shaped steel plate 1) on one side of the first-stage groove. The second-stage U-shaped steel plate, while ensuring that the verticality of the groove is not greater than 1/300;

④. After completing steps ① and ②, after the formation of the ground connection wall, perform grouting and sweeping of the grouting guide holes set on the grouting pipe, and inject the cement slurry at intervals of 5 meters under high pressure;

⑤. After the joint reinforcement grouting in step ④ is completed, protect the grouting pipe with a screw cap.

In the above technical scheme: when it is found that the joints of the continuous wall have signs of water seepage, the concrete on the surface of the first-stage groove cross-shaped groove plate and the second-stage groove U-shaped steel plate at the joint is chiseled off, and at the joint Weld the closed steel plate and fill it with quick-drying cement or plugging king.

In the above technical solution: the first-stage trough cross-shaped steel plate includes a horizontal steel plate and a vertical steel plate; the second-stage trough U-shaped steel plate includes flange plates and U-shaped steel plates at both ends, and the flange plate A grouting pipe is installed at the transition section between the U-shaped steel plate; the transverse steel plate is set opposite to the notch of the U-shaped steel plate, and is arranged at equal intervals on the transverse steel plate and the U-shaped steel plate There are concrete diversion holes.

In the above technical solution: anti-slip iron sheets are provided on the inner and outer sides of the reinforcement cage.

In the above technical solution: the distance between the vertical steel plate and the flange plate is 10-15 cm.

The utility model has the following advantages: 1. The construction of the utility model is convenient, as long as the residual sand bags and concrete agglomeration on the cross steel plate side of the first-stage groove are cleaned according to the design requirements, the U-shaped steel plate on the second-stage steel cage and the cross plate of the first-stage groove are cleaned. The reserved distance between the steel plates has a reasonable tolerance for construction errors, and they can bite each other to adapt to the lateral and horizontal deformation of the connecting wall.

2. Compared with the traditional cross steel plate joint, the utility model has greater rigidity and better water-stopping effect. During excavation, the steel plate can be welded from the side of the foundation pit to quickly seal the joint leakage water, and it can be dynamically injected through the reserved grouting hole. Advanced slurry reinforcement can effectively reduce the risk of ultra-deep foundation pit construction.

3. The utility model moves the anti-leakage grouting reinforcement measures of the joints from the outside of the wall joints to the inside of the wall joints. The water-stopping effect is good, the engineering cost is low, the construction quality is easy to check and judge, and the construction process is simple and mature. The limitation of the underground depth can well solve the problem of water leakage at the joints between the ground and the wall.

4. Compared with the prior art, this utility model can greatly reduce the risk of constructing ultra-deep foundation pit engineering in high pressure water-bearing formations, avoid a large amount of engineering costs and adverse social impacts caused by emergency rescue, and has significant economic benefits and social benefits.

Description of drawings

Fig. 1 is the structural connection diagram of the utility model.

Fig. 2 is a schematic diagram of the structure of the first-stage grooved cross-shaped steel plate in the utility model.

Fig. 3 is a schematic diagram of the structure of the U-shaped steel plate in the second stage of the utility model.

In the figure: first-stage groove cross-shaped steel plate 1, transverse steel plate 1.1, vertical steel plate 1.2, second-stage groove U-shaped steel plate 2, flange plate 2.1, U-shaped steel plate 2.2, steel cage 3, grout stop sheet 4, concrete diversion Hole 5, sealing steel plate 6, grouting pipe 7.

detailed description

The implementation of the present utility model will be described in detail below in conjunction with the accompanying drawings, but they do not constitute a limitation of the present utility model, they are only examples, and the advantages of the present utility model will become clearer and easier to understand.

Referring to Figures 1-3, it is a G-shaped joint for ground wall with pre-embedded repeatable grouting pipe, which includes a cross-shaped steel plate 1 for the first-stage groove and a U-shaped steel plate 2 for the second-stage groove. The cross-shaped steel plate for the first-stage groove The shaped steel plate 1 and the second-stage groove U-shaped steel plate 2 are pre-installed in the reinforcement cage 3 and are located between two adjacent concrete walls; The excavation side between 2 is provided with a sealing steel plate 6; the second-stage groove U steel plate 2 is located on one side of the first-stage groove cross-shaped steel plate 1, and the first-stage groove cross-shaped steel plate 1 includes a transverse steel plate 1.1 and vertical steel plate 1.2, the second-stage groove U-shaped steel plate 2 includes flange plates 2.1 and U-shaped steel plates 2.2 at both ends, and the transition between the flange plate 2.1 and the U-shaped steel plate 2.2 The section is equipped with a grouting pipe 7; one end of the transverse steel plate 1.1 extends into the notch of the U-shaped steel plate 2.2,

Holes 5 are arranged at equal intervals on the transverse steel plate 1.1 and the U-shaped steel plate 2.2; grout-stop iron sheets 4 are arranged on the inner and outer sides of the reinforcement cage 3; the vertical steel plate 1.2 and the wing The distance between the edge plates 2.1 is 10-15 cm. Described vertical steel plate 1.2 and flange plate 2.1 all stretch out each 5 centimeters of reinforcement cage 3 facing pit face. The thickness of the grout stopper 4 is 0.5 mm.

A method for pre-embedding a G-type joint of a ground-connecting wall of a repeatable grouting pipe of the present invention comprises the following steps;

①. According to the quality inspection of joint construction, including segmental water pressure test or cross-hole acoustic wave test, segmental high-pressure grouting from bottom to top;

②. Bind the reinforcement cage 3 according to the requirements of the design drawings, and install the first-phase groove cross-shaped steel plate 1 and the second-phase groove U-shaped steel plate 2 in the steel reinforcement cage 3; pour the first-phase groove cross-shaped steel plate 1- Side reinforcement cage 3;

③. When constructing the U-shaped steel plate 2 of the second-stage groove, clean the residual sandbags and concrete agglomerates on the side of the cross-shaped steel plate 1 of the first-stage groove, and pour the cross-shaped steel plate 1 on the side of the first-stage groove The second-stage U-shaped steel plate 2, while ensuring that the verticality of the groove is not greater than 1/300;

④. After step ① and step ② are completed, after the formation of the ground connection wall, the grouting guide hole provided on the grouting pipe 7 is grouted and swept, and the cement slurry is injected into sections at intervals of 5 meters under high pressure;

⑤. After the joint reinforcement grouting in step ④ is completed, protect the grouting pipe 7 with a screw cap.

When it is found that there are signs of water seepage in the joints of the diaphragm wall, the cause of the water seepage should be analyzed in time, and the joints of the ground connection wall below the excavation surface can be reinforced and grouted in advance through reserved grouting holes, so as to prevent problems before they happen.

Chisel off the concrete on the surface of the first-phase groove cross-shaped groove plate 1 and the second-phase groove U-shaped steel plate 2 at the joint, weld the closed steel plate 6 in the joint, and fill it with quick-drying cement or plugging king; The lower bottom surface of the sealing steel plate 6 located in the joint between the cross-shaped steel plate 1 of the first-stage groove and the U-shaped steel plate 2 of the second-stage groove is arranged from the upper bottom edge. It is determined by the size of the water head and also by the depth of the foundation pit on site.

The first-stage groove cross-shaped steel plate 1 includes a horizontal steel plate 1.1 and a vertical steel plate 1.2, and the horizontal steel plate 1.1 and the vertical steel plate 1.2 are perpendicular to each other;

The U-shaped steel plate 2 of the second-stage groove includes flange plates 2.1 and U-shaped steel plates 2.2 at both ends, and a grouting pipe 7 is installed at the transition section between the flange plate 2.1 and the U-shaped steel plate 2.2 The notch of described transverse steel plate 1.1 and described U-shaped steel plate 2.2 is oppositely arranged, is provided with holes 5 at equal intervals on described transverse steel plate 1.1 and U-shaped steel plate 2.2, and described transverse steel plate 1.1 consists of two The two small steel plates are respectively located on both sides of the vertical steel plate 2.2; each small steel plate is equidistantly provided with concrete diversion holes 5 of the same size as the U-shaped steel plate 2.2 , the concrete diversion hole 5 facilitates the flow of concrete mortar between the cross-shaped steel plate 1 of the first-stage groove and the U-shaped steel plate 2 of the second-stage groove.

The parts not described in detail above are all prior art.

Claims (5)

1. A G-type joint of ground wall with pre-embedded repeatable grouting pipe is characterized in that: it comprises a first-stage groove cross-shaped steel plate (1) and a second-stage groove U-shaped steel plate (2), and the first-stage The grooved cross-shaped steel plate (1) and the second-stage grooved U-shaped steel plate (2) are pre-installed in the reinforcement cage (3) and are located between two adjacent concrete walls; the first-phase grooved cross-shaped steel plate There is a sealing steel plate (6) on the excavation side between (1) and the U-shaped steel plate (2) of the second-stage groove; On one side, the first-stage groove cross-shaped steel plate (1) includes a transverse steel plate (1.1) and a vertical steel plate (1.2), and the second-stage groove U-shaped steel plate (2) includes flange plates (2.1) at both ends and U-shaped steel plate (2.2), a grouting pipe (7) is installed at the transition section between the described flange plate (2.1) and the described U-shaped steel plate (2.2); the described transverse steel plate (1.1) One end stretches into the notch of the U-shaped steel plate (2.2), and concrete diversion holes (5) are arranged at equal intervals on the described transverse steel plate (1.1) and the U-shaped steel plate (2.2); The inner and outer sides of the reinforcement cage (3) are all provided with anti-slip iron sheets (4). 2. A G-type joint of ground wall with pre-embedded re-grouting pipe according to claim 1, characterized in that: the vertical steel plate (1.2) and the flange plate (2.1) The distance between them is 10-15 cm. 3. A G-type joint for ground wall with pre-embedded repeatable grouting pipe according to claim 1 or 2, characterized in that: the vertical steel plate (1.2) and the flange plate (2.1 ) with a distance of 15 cm. 4. A G-type joint for ground wall with pre-embedded repeatable grouting pipe according to claim 3, characterized in that: said vertical steel plate (1.2) and flange plate (2.1) both protrude from the steel bars Cage (3) faces each 5 centimeters of pit face. 5 . A G-type joint for ground wall with pre-embedded repeatable grouting pipe according to claim 4 , characterized in that: the thickness of the grout stop iron sheet ( 4 ) is 0.5 mm.