CN113585237B - Ground connecting wall joint and construction method of ground connecting wall - Google Patents

Abstract

The application relates to a ground connecting wall joint and a construction method for the ground connecting wall. The ground connecting wall joint is used to connect two adjacent unit wall sections, and includes an isolation plate and a perforated plate; the isolation plate is used to be embedded in adjacent Between two unit wall sections, the perforated plate is fixedly connected to the isolation plate, and the perforated plate is provided with through holes at intervals, the perforated plate is used to be embedded in the unit wall section, and the through holes are located in the unit wall At least two perforated plates are fixedly connected to both sides of the isolation plate. The perforated plate and the unit walls on both sides form a close and fixed engagement, which can withstand the shear force on the vertical joints of the underground diaphragm wall, and make the adjacent unit walls form a whole to jointly bear the vertical load of the upper structure, so as to realize the coordinated unit wall. The uneven settlement of the body and the two perforated plates increase the water flow path required for the seepage water, so that the local connecting wall joints also have better water-stop performance.

Description

Ground connecting wall joint and ground connecting wall construction method

technical field

The present application relates to the field of infrastructure engineering, in particular to a ground connecting wall joint and a ground connecting wall construction method.

Background technique

As an effective water interception, anti-seepage, load-bearing and water-retaining structure, the underground diaphragm wall is often used in the support construction of deep foundation pits, municipal trenches, culverts, revetments, dry docks and other projects.

In actual construction, affected by factors such as geological conditions, surrounding environment, foundation pit depth, etc., underground diaphragm walls usually use one or more joint forms to connect two adjacent unit wall sections to each other to solve the problem of connecting two unit wall sections. Water leakage at seams and joint integrity issues.

The I-beam joint of the underground diaphragm wall is a common joint form, but due to the short wing plate of the I-beam joint, it is only wrapped on the joint of the unit wall section on the two sides, and the anti-seepage performance is limited.

SUMMARY OF THE INVENTION

In order to improve the anti-seepage performance and overall stability of the underground continuous wall, the present application provides a ground connecting wall joint and a ground connecting wall construction method.

In the first aspect, the application provides a ground-to-wall joint, which adopts the following technical solutions:

A ground connection wall joint is used to connect two adjacent unit wall sections, including an isolation plate and a perforated plate; the isolation plate is used to be embedded between the two adjacent unit wall sections, and the perforated plate is fixed connecting the isolation plates, and the perforated plates are provided with through holes at intervals, the perforated plates are used to be embedded in the unit wall section, and the through holes are located in the unit wall section;

Both sides of the isolation plate are fixedly connected with at least two perforated plates.

By adopting the above technical solution, the perforated plate and the unit walls on both sides form a tight occlusion effect, which can withstand the shear force on the vertical joints of the underground diaphragm wall, and make the adjacent unit walls form a whole to jointly undertake the vertical direction of the upper structure. load, and realize the uneven settlement of the coordinated unit wall. At the same time, because the two perforated plates increase the flow path required for the seepage water, the local connecting wall joints also have good water-stop performance.

Preferably, the perforated plate is perpendicular to the isolation plate.

Preferably, the perforated plate includes a connecting plate and an engaging plate; the connecting plate is fixedly connected to the isolation plate; the engaging plate is located at an end of the connecting plate away from the partition, and the through hole is provided on the engaging plate.

In the second aspect, the application provides a ground-connecting wall construction method, which adopts the following technical scheme:

A ground-connecting wall construction method, using the above-mentioned ground-connecting wall joint, includes the following steps:

For the construction of supporting piles and guide walls, excavate guide grooves on the peripheral side of the earthwork to be excavated, construct reinforcement piles on the ground on the side walls of the guide grooves, install and fix the prefabricated guide walls in the guide grooves, and tamp the surface soil ;

A groove is formed, the wall protection mud is injected into the guide groove, and the grab bucket is extended into the guide groove for digging to form a unit groove section;

Hoisting steel cages and joint boxes, welding multiple steel bars to form a steel cage, and welding and fixing the steel cage and the ground connecting wall joints, hoisting the steel cages into the unit groove section, and then hoisting the joint box into the unit groove section;

Underwater concrete pouring, the concrete is poured into the unit groove section, and the unit wall section is formed after solidification;

Repeat the above steps until the underground diaphragm wall is formed.

By adopting the above technical scheme, when forming a groove, the soil body at the groove wall is reinforced by the reinforcement piles, so as to limit the movement of the soil body and reduce the probability of the collapse of the groove section.

Preferably, the reinforcing pile is located on the side of the guide groove facing the earthwork to be excavated.

Preferably, the reinforcing piles are cement mixing piles.

Preferably, during the construction of the step supporting pile and the guide wall, the method further includes: excavating drainage ditches around and setting up water collecting wells during the water injection and pre-mixing construction.

Preferably, the entrance of the guide wall is at least 100mm higher than the ground.

By adopting the above technical solution, it is prevented that garbage and rainwater are washed into the guide groove formed by the guide wall to contaminate or dilute the mud.

Preferably, the width of the opening of the guide wall is greater than the width of the grab.

By adopting the above technical solution, the guide wall is widened by 50mm during construction, so as to facilitate the smooth entry and exit of the grab bucket, drill bit, steel cage and other components in the subsequent construction process.

To sum up, the present application includes at least one of the following beneficial technical effects:

1. The perforated plate and the unit walls on both sides form a tightly embedded and fixed occlusal effect, which can withstand the shear force on the vertical joints of the underground diaphragm wall, and make the adjacent unit walls form a whole to jointly bear the vertical load of the upper structure to achieve coordination. The uneven settlement of the unit wall, and at the same time, the two perforated plates increase the flow path required for the leakage water, so that the local connecting wall joints also have better water-stop performance;

2. When forming a groove, rely on reinforcement piles to reinforce the soil at the wall of the groove to limit the movement of the soil, especially for the interactive stratum of silty soft soil and sandy soil, which effectively reduces the probability of the collapse of the groove section.

Description of drawings

Figure 1 is a schematic diagram of the structure of the ground wall joint.

Fig. 2 is a schematic diagram of the position of the guide groove and the reinforcement pile.

Explanation of reference numerals: 1, isolation plate; 2, perforated plate; 21, connecting plate; 22, bite plate; 23, through hole;

3. Guide groove; 4. Reinforcement pile; 5. Guide wall.

Detailed ways

The present application will be further described in detail below in conjunction with accompanying drawings 1-2.

The embodiment of the present application discloses a ground wall joint for connecting two adjacent unit wall sections

Referring to FIG. 1 , the ground wall joint includes an isolation plate 1 and a perforated plate 2 ; both the isolation plate 1 and the perforated plate 2 are plates.

The isolation board 1 is used to be embedded between two adjacent unit wall segments; at least two perforated boards 2 are fixedly connected to both sides of the isolation board 1 . In this embodiment, two perforated plates 2 are welded on both sides of the isolation plate 1 .

The perforated plate 2 includes an integrally formed connecting plate 21 and an engaging plate 22 . The connecting plate 21 is fixedly connected to the isolation plate 1 by welding; the engaging plate 22 is located at one end of the connecting plate 21 away from the partition, and the engaging plate 22 is provided with through holes 23 at intervals. In this embodiment, the through holes 23 are set as square holes . In one embodiment, the perforated plate 2 is perpendicular to the isolation plate 1; in another embodiment, in the two perforated plates 2 located on the same side of the isolation plate 1, the distance between the two engaging plates 22 is greater than the distance between the two connecting plates 21. spacing.

During the construction of the ground connection wall, the concrete slurry is placed on one side of the isolation plate 1 and covers the perforated plate 2 , and part of the concrete slurry is filled into the through hole 23 . After the concrete slurry is solidified, a unit wall is formed, so that the perforated plate 2 is embedded in the unit wall section, and the through hole 23 is located in the unit wall section, so that the perforated plate 2 and the unit wall are tightly embedded and fixed.

The implementation principle of a ground connecting wall joint in the embodiment of the present application is as follows: the perforated plate 2 forms a close-fitting engagement with the unit walls on both sides, which can withstand the shear force on the vertical joints of the underground continuous wall, and make the adjacent unit walls The body is formed as a whole to jointly bear the vertical load of the upper structure, so as to realize the uneven settlement of the coordinated unit wall. At the same time, because the two perforated plates 2 increase the flow path required for the seepage water, the local connecting wall joints also have better performance. Water-stopping properties.

The embodiment of the present application also discloses a ground connection wall construction method, comprising the following steps:

S10 Construction of supporting piles and guide walls 5, referring to Figure 2, excavating guide grooves 3 on the peripheral side of the earthwork to be excavated, and constructing reinforcement piles 4 on the ground on the side walls of the guide grooves 3, and installing the prefabricated guide walls 5 to the guide grooves 5 In the groove 3 and fixed, and tamp the surface soil.

Specifically, first level the site, and then place 15cm outside the periphery of the soil to be excavated to measure the axis control piles of the underground wall. The control piles are all protected piles. The elevation is introduced into the site, and the closed back-measurement method is used to set the benchmarking point in the site, so as to control the elevation of the guide wall 5 and the underground diaphragm wall.

The position of the pile is controlled based on the axis of the underground wall, the guide channel 3 is excavated, and then the reinforcement pile 4 is constructed. The reinforcement piles 4 are cement mixing piles and are located on the side of the guide groove 3 facing the earthwork to be excavated; if necessary, the reinforcement piles 4 can be constructed on both sides of the guide groove 3 .

At the same time, the technical parameters of the cement mixing pile: the reinforcing agent is ordinary Portland cement with a strength grade of 42.5 and above, the water-cement ratio is controlled between 0.45-0.55, and the amount of cement per meter is not less than 75kg. At the same time, in the silt layer and the silty fine sand layer, the mixing and lifting speed of the shotcrete shall not be greater than 0.8m/min, and the construction interval of the overlapping mixing piles shall not be greater than 24h.

When the surface of the site is hard and needs to be pre-mixed by water injection, drainage ditches should be excavated around, and water collection wells should be set up, and the positions of the drainage ditches and water collection wells should not affect the construction of the mixer.

In addition, the upper opening of the prefabricated guide wall 5 is at least 100mm higher than the ground to prevent garbage and rainwater from rushing into the guide groove 3 formed by the guide wall 5 to contaminate or dilute the mud; the opening width of the guide wall 5 is larger than that of the grab bucket. The width (the guide wall 5 is relaxed by 50mm during construction), so as to facilitate the smooth entry and exit of the grab bucket, drill bit, steel cage and other components in the subsequent construction process.

S20 Prepare mud for wall protection and construct; the mud should be stored for 24 hours after mixing, and can be used after the mud material is fully hydrated.

S30 is formed into a groove, the wall-protecting mud is injected into the guide groove 3, and the grab bucket is extended into the guide groove 3 for digging to form a unit groove section.

Specifically, the center plane of the grab bucket should match the center plane of the guide wall 5 . The grooves are generally excavated at intervals. The standard groove sections should be formed in three sequences. First, dig both sides, and then dig the middle partition wall. The length of the middle partition wall should be less than the opening length of the grab bucket, so that the grab bucket can be evenly covered by force. Excavate the partition wall to ensure the verticality of the groove and avoid verticality deviation.

When the groove section is excavated to 0.5 meters from the bottom of the wall, the excavation is stopped, and the joints are brushed. It is required to brush the walls for the last time.

After the entire construction trough section is dug to the design depth, it is stopped for 1 hour, and then at the design depth along the length of the trough section, the bottom bucket is grabbed and excavated once for every 1m of movement to remove the sediment at the bottom of the trough.

After the wall is brushed, remove the sediment at the bottom of the tank. During the removal process, it is necessary to strictly control the footage of each bucket to be controlled at about 15cm, and the method of slowly grasping and lifting must be used to remove 0.5 meters of soil left at the bottom of the tank from one end to the other. The sediment and sludge at the bottom of the tank shall ensure that the thickness of the sedimentary sludge is not more than 100mm.

After the trough is completed, the trough section inspection uses a hammer, steel ruler, ultrasonic wall measuring instrument, and mud specific gravity meter to detect the depth, width, plane position, verticality of the trough section wall surface, the thickness of the sediment and the specific gravity of the mud at the bottom of the trough. Whether the quality of the segment meets the design and specification requirements.

In addition, when forming a trough, the mud supply and treatment equipment should meet the requirements of mud usage, the mud surface should be higher than the groundwater level, and the distance from the ground should not be greater than 300mm, until the concrete pouring in the subsequent step S50 is completed.

When the hydraulic grab is grooved to the rock surface, if the designed end hole elevation cannot be reached, the impact pile driver shall be used for rock entry treatment. The specific method is to first use a round hammer to form a hole, and then use a square hammer to trim the edge to form a groove.

S40 hoisting steel cages and joint boxes, welding multiple steel bars to form a steel cage, and welding and fixing the steel cage and the ground connecting wall joint, hoisting the steel cage into the unit groove section, and then hoisting the joint box into the unit groove section.

Specifically, two sets of reinforcement cage platforms are arranged on site for the reinforcement cages to be fabricated on the reinforcement cage platforms; at the same time, the reinforcement cage platforms are leveled with instruments, and the flatness of the reinforcement cage platforms is checked at any time to ensure that the reinforcement cages are flat. precision.

Welding is used for the connection of steel bars in the production of steel cages. The joint ratio of the same section should not be greater than 50%, and should be staggered by 500mm for welding; the joint welding of vertical bars must ensure that the two bars are vertically consistent, and must not be twisted or displaced. Any unspecified weld thickness is 6mm, and full welding is required to ensure the strength of the steel cage.

At the same time, the ground wall joint is also welded on site. The processed Q235B isolation plate 1 is laid on the ground, and the line is marked and positioned according to the design size, and the position of the perforated plate 2 is determined for later processing. Fix the perforated plate 2 at the pre-determined white line, and then use carbon dioxide shielded welding to fully weld it with the isolation plate 1 on both sides. The thickness of the weld is 6mm. After welding the two perforated plates 2 on one side of the isolation plate 1, In turn, fix it on the ground smoothly, and then use the same method to weld the front two pieces to complete the welding of the rear two perforated plates 2.

The connection between the ground wall joint and the reinforcement cage is mainly by welding the horizontal bar to the isolation plate 1, using E50XX welding rod for double-sided welding, the thickness of the welding seam is 6mm, and the welding length meets the requirements of 5d.

Under the action of gravity, the joint box is vertically lowered to the joint of the ground connecting wall, and the back side of the joint box is filled with sandbags to resist the lateral pressure generated during the pouring of the ground connecting wall.

S50 Underwater concrete pouring, the concrete is poured into the unit groove section, and the unit wall section is formed after solidification.

Specifically, it mainly includes the process of cleaning the tank, mixing concrete, equipment configuration, pouring and other processes.

After the cleaning of the tank is completed and the mud is checked and qualified, the concrete will be poured within 4 hours. When pouring concrete, a set of concrete compressive test blocks and a set of concrete impermeability test blocks should be left in each unit groove section. In addition, the impermeability grade of the diaphragm wall is P6, the strength of the underground wall is C35, the slump should be 180-210mm, and the pipe type underwater concrete is poured. . In order to meet the strength requirements, the mixing ratio should be designed to increase by at least 5Mpa.

At the same time, during the pouring operation, if it is found that the conduit is leaking, blocked, or mud is mixed into the concrete, the irrigation should be stopped immediately and treated, and records should be made to ensure the strength requirements of the ground connection wall.

S60 pulls out the joint box; after the concrete is solidified, pull up the joint box.

S70 Repeat the above steps S20-60 until the underground diaphragm wall is formed.

The implementation principle of a ground connection wall construction method in the embodiment of the present application is as follows: when a groove is formed, the soil body at the groove wall is reinforced by means of reinforcement piles 4, the movement of the soil body is restricted, and the probability of collapse of the groove section is reduced; the construction of the ground connection wall is completed. Then, the wall joints are connected together to make the adjacent unit walls form a whole and jointly bear the vertical load of the upper structure, so as to realize the uneven settlement of the coordinated unit walls. The flow path makes the local wall joint also have better water-stop performance.

The above are all preferred embodiments of the present application, and are not intended to limit the protection scope of the present application. Therefore: all equivalent changes made according to the structure, shape and principle of the present application should be covered within the scope of the present application. Inside.

Claims (1)

1. A ground wall joint for connecting two adjacent unit wall sections, characterized in that: it comprises an isolation plate (1) and a perforated plate (2); the isolation plate (1) is used to be embedded in a phase Between two adjacent unit wall segments, the perforated plate (2) is fixedly connected to the isolation plate (1), and the perforated plate (2) is provided with through holes (23) at intervals, and the perforated plate (2) is used for is embedded in the unit wall section, so that the through hole (23) is located in the unit wall section; Two perforated plates (2) are fixedly connected to both sides of the isolation plate (1); The perforated plate (2) includes a connecting plate (21) and an engaging plate (22); the connecting plate (21) is fixedly connected to the isolation plate (1); the engaging plate (22) is located away from the connecting plate (21) one end of the isolation plate (1), and the through hole (23) is provided on the occlusal plate (22); In the two perforated plates (2) located on the same side of the isolation plate (1), the distance between the two occlusal plates (22) is greater than the distance between the two connecting plates (21); The isolation plate (1) is used for welding connection of the horizontal bars of the reinforcement cage.

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