CN110528501A - High rich water faces sea area diaphragm wall and connects sealing device - Google Patents

Abstract

The invention belongs to the technical field of foundation pit support, and relates to a water-stopping device for a diaphragm wall joint in a high-water-rich area near the sea. The horizontal ribs of the diaphragm wall are mechanically connected with the vertical main ribs of the diaphragm wall. Above; the galvanized iron sheet is installed on the outside of the I-shaped steel plate, the galvanized iron sheet is spot-welded with the layered reinforcement, the I-shaped steel is welded to the first wall reinforcement cage, and the U-shaped stirrup is welded to the horizontal reinforcement of the continuous wall on one side. Note The grout pipe and the reinforcement cage of the second wall are bound and lapped, and the reinforcement cage of the second wall is embedded in the I-shaped steel plate wing during hoisting; the sandbags are piled on the outside of the web of the I-shaped steel plate joint, and the height of the underfill is continuous underground The height of the wall; its waterproof effect is ideal, which can effectively prevent the concrete from flowing around, and the setting of the steel flower tube ensures the waterproof effect of the joints.

Description

A water-stop device for diaphragm wall joints in high-water-rich coastal areas

Technical field:

The invention belongs to the technical field of foundation pit support, and relates to a water-stopping device for joints of continuous walls in high-water-rich coastal areas, in particular to a water-stopping device with I-shaped steel as the joint.

Background technique:

Diaphragm wall is an important form of deep foundation pit support structure. Its basic process includes: guide wall construction, mud preparation, trench construction, steel cage production, steel cage hoisting, joint treatment, underwater concrete pouring, etc. , wherein the construction of the joints of the underground diaphragm wall (especially in a high-rich water-facing area) is a technical problem affecting the anti-seepage and water-proofing of the underground diaphragm wall.

At present, the commonly used construction methods at the joints of underground diaphragm walls include the following: One is the circular joint pipe technology: after cleaning the bottom and changing the grout, it is inserted into one or both ends of the groove section. First, it is characterized by low cost, mature method, and wide application, but it is difficult to control the time of extubation, and the waterproof effect is not ideal; the second is "one" or "ten" steel plate joint: after the groove is formed, it is placed into the groove section with the steel cage , as a one-time waterproof device, the two sides of the steel plate are embedded in the two continuous walls of the front and back construction. Its characteristics are widely used and the cost is cheap, but the concrete at the joints is poorly contacted and sand is easy to be included; the third is "gong" or "king" steel Joint: After the groove is formed, put it into the corresponding groove section as a one-time waterproof device. The steel cage is embedded in the steel plate wing plate. It is characterized by being suitable for water-rich strata, with good integrity and outstanding waterproof effect. The disadvantage is that it is expensive; four. It is the waterproof joint of the rotary grouting pile: After the continuous wall is poured, the rotary grouting pile is driven into the outer side of the joint for waterproofing. It is characterized by being suitable for the weak bottom layer and has a general waterproof effect. Hose joint: brought into the predetermined position by a special joint pipe, and the joint pipe is pulled out after the next slot section is slotted. It is suitable for shallow continuous walls and prevents circumvention, but its construction is complicated and the overall rigidity is poor, such as CN200910193231. 8 discloses an installation device and method for an underground diaphragm wall joint flexible waterstop. The installation device is a joint pipe structure made of steel plates or section steel with a ratio of width to thickness close to 1. A part of the joint that is in contact with concrete At least one installation groove for installing a rubber water stop belt is provided on the side, and the width of the opening of the installation groove is slightly smaller than the width of the groove cavity. Since the aspect ratio of the joint pipe is close to 1. In recent years, grouting joints have appeared. For example, 201810132066.4 discloses a groutable underground diaphragm wall joint and its construction method. The underground diaphragm wall joint, when the ground wall joint is connected by a rigid joint, the two grouting pipes are fixed on the side of the rigid joint facing the soil by a ring, and when the flexible joint is used, the two grouting pipes are respectively fixed on The two ends of the steel cage facing the soil surface, the specific construction includes: the construction of the guide wall, the unit groove section and the underground diaphragm wall; however, due to the poor engineering geological conditions, the quality of the groove formed by the underground diaphragm wall is a major and difficult point, and the construction cost of this water-stopping method is high.

Therefore, based on the different construction methods and engineering geological conditions of various underground diaphragm wall joints, it is particularly important to reasonably select the structural form of underground diaphragm wall joints.

Invention content:

The purpose of the present invention is to overcome the shortcomings of the prior art, and to design and provide a water-stopping device for diaphragm wall joints in high-water-rich coastal areas, so as to prevent seepage and water at the joints of underground diaphragm walls during construction and support.

In order to achieve the above object, the main structure of the underground diaphragm wall joint water stop device in the high-rich water near the sea area of the present invention includes I-shaped steel plates, diaphragm wall horizontal ribs, diaphragm wall vertical main ribs, U-shaped stirrups, galvanized iron sheets, layered steel bars , steel flower pipe, grouting pipe, reinforcement cage for the first wall width, reinforcement cage for the second wall width and sandbags; the horizontal reinforcement of the continuous wall and the vertical main reinforcement of the continuous wall are mechanically connected, and the steel flower pipe is bound and lapped on the reinforcement cage for the first wall width ; The galvanized iron sheet is installed on the outside of the I-shaped steel plate, and the galvanized iron sheet and the layered steel bar are spot welded, and the I-shaped steel is welded to the first wall reinforcement cage, and the weld length is 100mm; The grouting pipe and the second wall reinforcement cage are bound and overlapped, and the second wall reinforcement cage is hoisted and embedded in the I-shaped steel plate wing; sandbags are piled on the outside of the I-shaped steel plate joint web, and the lower The fill height is the height of the underground diaphragm wall.

The I-shaped steel plate of the present invention is welded by H-shaped steel plate, the width of the flange is 400mm, the thickness of the flange is 10mm, the height of the web is 160mm, and the thickness of the web is 10mm.

The type and size of the horizontal reinforcement of the diaphragm wall and the vertical main reinforcement of the diaphragm wall are selected according to the needs of the project.

The type and spacing of the U-shaped stirrups in the present invention are the same as those of the horizontal bars of the continuous wall, and the bending angle of the U-shaped stirrups is 45°, so that the second wall reinforcement cage can be better embedded in the I-beam during hoisting Inside the wing plate, it is convenient for construction.

The galvanized iron sheet of the present invention has a thickness of 0.3 mm and a width of 500 mm. When concrete is poured in the trough section, it is stretched outwards, and the galvanized iron sheet prevents concrete from flowing into the adjacent ungrooved trough section.

The type and size of the layered steel bars in the present invention are C20, and they are spot-welded with galvanized iron sheets at a distance of 100 mm from the edge of the I-shaped steel plate.

The diameter of the steel flower pipes described in the present invention is A50, its wall thickness is 3mm, and its height is equivalent to the height of the underground diaphragm wall. The role of the steel flower pipe is to carry out grouting reinforcement after the water-stop structure is formed and before the excavation of the foundation pit to ensure the water-stop effect at the joints. The size of the grout pipe is the same as that of the steel flower pipe.

The specific process of the present invention to realize the waterproofing of the joints of the underground diaphragm wall in the area of high-rich water near the sea is as follows:

(1) Pouring guide wall: use the existing construction technology to level the site → measure and stake out → excavate the guide wall trench and dispose of waste soil → tie the guide wall reinforcement, install the outer formwork of the vertical wall → pour the wall concrete → remove the formwork and add horizontal Support→layered earthwork backfilling in the trench;

(2) Mud preparation: In the process of trough formation, the mud plays the role of wall protection, slag carrying, cooling equipment, and cutting soil lubrication. The mud with good performance can ensure the stability of the trough wall during trough formation and prevent the trough from collapsing. When pouring, it plays an extremely important role in ensuring the quality of concrete pouring; the mud mix ratio is designed according to the geology, groundwater properties and construction experience, so that the configured mud index meets the construction requirements. The process of mud configuration is: first add water to After 1/3 of the mixing drum, start the pulping machine, and then add bentonite powder while continuously adding water to the quantitative water tank. After stirring for 10 minutes, add CMC liquid and alkali powder and other admixtures and continue stirring for 10 minutes, then stop stirring and put it into the new pulp tank In the middle, use it after standing for 24 hours of puffing;

(3) Excavation of the trench section in phase I: the first trench is used as the test trench section, and various parameters and data of the trench construction are collected. After the trench is tested, the ground connection wall is routinely trenched, and the phase I is determined according to the design drawings and the guide wall The excavation position of the slot section is excavated by the slotting machine; the mud wall is used when the slot is formed, and the slot hole is checked and accepted according to the relevant specifications after the slot is completed. Carry out tank wall cleaning; this process is to control the verticality and mud parameters of the formal trench construction process, ensure the continuity of project implementation, and achieve the purpose of guiding construction;

(4) Reinforcement cage production: The first wall width reinforcement cage is manufactured according to the construction requirements by the existing technology and then welded with the I-shaped steel plate, and the galvanized iron sheet and layered steel bars are installed at the same time;

(5) Step (3) After the cleaning of the tank, the quality of the tank and the mud index are inspected. After passing the test, the joint box is lifted, the first steel cage is lowered to the predetermined position, and sandbags are filled outside the I-shaped steel plate joint to prevent Outflow of concrete; in order to reduce the vertical settlement of the underground diaphragm wall and the corresponding surface settlement, grouting reinforcement is carried out at the joints of the I-shaped steel plates with preset steel flower pipes, and then the first underground wall is poured underwater through the pre-buried grouting pipes. Diaphragm wall, pull out the joint box after pouring is completed;

(6) After the completion of Phase II of the adjacent tank section, first use the wall brusher to remove the hard objects that have not fallen off, and then use the wall brusher wire brush to scrub the I-shaped steel plate at the end of the Phase I tank from top to bottom, up and down Brush several times until there is no mud debris on the brush, the accumulation at the bottom of the hole will no longer increase, and the joint between the new and old concrete will be clean and dense after brushing the wall;

(7) Hanging the joint box, hoisting and embedding the second wall reinforcement cage in the I-shaped steel plate wing plate, pouring concrete underwater through the grouting pipe, and pulling out the joint box after the pouring is completed;

(8) The rest of the walls are poured sequentially according to the above steps until the last continuous wall is poured.

Compared with the prior art, the present invention is more suitable for the construction method using I-beam as the joint of the underground diaphragm wall in high-rich water and coastal areas, and the waterproof effect is ideal; filling sandbags on the outside of the galvanized iron sheet and I-beam can effectively prevent concrete Circumvention; and the use of special steel wire brushes sold in the market has a good wall brushing effect, which is conducive to strengthening the integrity of the concrete and enhancing the waterproof effect; the setting of the steel flower tube further ensures the water-stopping effect at the joints.

Description of the drawings:

Fig. 1 is a schematic diagram of the principle structure of the main structure of the underground diaphragm wall joint water-stop device in the high-rich water near the sea area of the present invention.

Fig. 2 is a three-dimensional perspective view of the main structure of the underground diaphragm wall joint water-stopping device in the high-rich water near the sea area of the present invention.

Fig. 3 is a schematic diagram of the structure of the I-shaped steel plate of the present invention.

Fig. 4 is a schematic diagram of the structure of the steel flower tube of the present invention.

Detailed ways:

The present invention will be further described below by way of embodiments and in conjunction with the accompanying drawings.

Example 1:

The main structure of the underground diaphragm wall joint water-stop device in the high-rich water near the sea area of this embodiment includes I-shaped steel plate 1, diaphragm wall horizontal rib 2, diaphragm wall vertical main rib 3, U-shaped stirrup 4, galvanized iron sheet 5, layering strip Steel bar 6, steel flower pipe 7, grouting pipe 8, first wall reinforcement cage 9, second wall reinforcement cage 10 and sandbag 11; diaphragm wall horizontal reinforcement 2 and diaphragm wall vertical main reinforcement 3 are mechanically connected, and steel flower pipe 7 is bound Lap on the first wall reinforcement cage 9; the galvanized iron sheet 5 is installed on the outside of the I-shaped steel plate 1, the galvanized iron sheet 5 and the bead reinforcement 6 are spot welded, and the I-shaped steel 1 is welded to the first wall reinforcement cage 9 , the weld length is 100mm; the U-shaped stirrup 4 and the horizontal bar 2 of the continuous wall are welded on one side, the grouting pipe 8 and the second wall reinforcement cage 10 are tied and overlapped, and the second wall reinforcement cage 10 is embedded in the hoisting In the I-shaped steel plate 1 wing plate; 11 sandbags are stacked outside the web of the I-shaped steel plate 1 joint, and the height of the underfill is the height of the underground diaphragm wall.

The I-shaped steel plate 1 described in this embodiment is welded by H-shaped steel plates. The width of the flange is 400 mm, the thickness of the flange is 10 mm, the height of the web is 160 mm, and the thickness of the web is 10 mm.

The type and size of the horizontal ribs 2 of the diaphragm wall and the vertical main ribs 3 of the diaphragm wall described in this embodiment are selected according to the needs of the project.

The type and spacing of the U-shaped stirrups 4 described in this embodiment are the same as those of the horizontal ribs 2 of the continuous wall, and the bending angle of the U-shaped stirrups 4 is 45°, so that the second wall width reinforcement cage 10 can be better embedded during hoisting. It is fixed in the I-beam 1 wing plate, which is convenient for construction.

The galvanized iron sheet 5 described in this embodiment has a thickness of 0.3mm and a width of 500mm. When concrete is poured in the groove section, it is stretched outwards, and the galvanized iron sheet 5 prevents the concrete from flowing into the adjacent ungrooved groove section.

The type and size of the layered steel bars 6 in this embodiment are C20, and they are spot welded with the galvanized iron sheet 5 at a distance of 100 mm from the edge of the I-shaped steel plate 1 .

The diameter of the steel flower pipe 7 described in this embodiment is A50, its wall thickness is 3mm, and its height is equivalent to the height of the underground diaphragm wall. 9 binding connections, the effect of the steel flower pipe 7 is to carry out grouting reinforcement before the excavation of the foundation pit after the water-stop structure is formed, to ensure the water-stop effect at the joint, and the size of the grouting pipe 8 is the same as that of the steel flower pipe 7.

Example 2:

In this embodiment, the joint water-stop device described in Embodiment 1 is applied to the construction of an underground diaphragm wall of a certain subway station. The specific construction process is as follows:

(1) Pouring guide wall: After the measurement and setting-out is completed, the construction of the guide wall begins. The construction quality of the guide wall is directly related to the construction quality of the underground diaphragm wall. The cross-section of the guide wall is made of inverted "L" cast-in-place reinforced concrete, with HRB400C12@200 steel skeleton evenly distributed, and the guide wall is made of C30 concrete. Before excavation of the guide wall, the excavation trench must be manually excavated. When the excavator is operating, a special person must stand by Supervise the construction, then bind the guide wall reinforcement and vertical formwork, pour C30 concrete, remove the formwork and add lateral support, and finally backfill the earthwork in layers in the groove;

(2) Mud preparation: During the trough forming process, the mud plays the role of wall protection, slag carrying, cooling equipment, and cutting soil lubrication. The mud with good performance can ensure the stability of the trough wall during trough forming and prevent the trough from collapsing. When pouring, it plays an extremely important role in ensuring the quality of concrete pouring; the mud mix ratio is designed according to the geology, groundwater properties and construction experience in Qingdao City, so that the configured mud index meets the construction requirements (the mud proportion is controlled at 1.1g/cm ³ ~ 1.25g/ ^cm3 , viscosity between 25 ~ 30s), the slurry configuration method is: first add water to 1/3 of the mixing drum, start the pulping machine, and then add bentonite while continuously adding water to the quantitative water tank powder, after stirring for 10 minutes, add additives such as CMC liquid and alkali powder and continue stirring for 10 minutes, then stop stirring and put it into the new pulp tank, and use it after standing for 24 hours of puffing;

(3) Phase I trench section excavation: In order to control the verticality and mud parameters of the formal trenching construction process, ensure the continuity of the project implementation, and achieve the purpose of guiding the construction, the first trenching is used as the test trench section, and the excavation of the trenching construction is collected. Various parameters and data, etc. After the trench is tested, the ground connection wall is conventionally formed, and the excavation position of the first phase of the trench is determined according to the design drawings and the guide wall. When the groove is formed, mud is used to protect the wall. After the groove is formed, the groove hole is checked and accepted according to the relevant specifications. After the groove section is completed, the hard objects that have not fallen off are removed with an oblique shovel. The wall brush uses a special wall brush, and the height of the wall brush is 3 meters, weighing 4 tons, one side is a slanted steel shovel, which is used to remove abrasive belts, concrete, etc. that are firmly adhered to the steel plate; The tank machine cleans the bottom of the tank wall;

(4) steel cage making: steel bar is derusted earlier before making, adopts mold method forming process to make steel cage, strictly controls welding quality during welding, adopts existing technology to make after the first wall reinforcement cage 9 is done by construction requirements and I-shaped steel plate 1 is welded, and an anti-winding galvanized iron sheet 5 with a thickness of 0.3mm and a width of 500mm is installed on the outside of the I-shaped steel at the I-shaped steel joint. The overlapping width of the galvanized iron sheet 5 and the I-shaped steel 1 is not less than 100mm, and a bead is used Steel bar 6 is fixedly welded;

(5) Step (3) After the cleaning of the tank, the quality of the finished tank and the mud index are inspected. After passing the inspection, the joint box is hoisted, and the first steel cage 9 is hoisted as a whole by double-machine hoisting, and a 130t crawler crane is used for the overall hoisting. For the main hoist, a 55t crawler crane is used as the auxiliary hoist. The hoisting points of the steel cage are set at 4 points for the main hoist and 6 points for the auxiliary hoist, and lowered to a predetermined position. Sandbags 11 are filled outside the I-shaped steel plate 1 joint to prevent the concrete from flowing out; for To reduce the vertical settlement of the underground diaphragm wall and the corresponding surface settlement, use the preset steel flower pipe 7 to carry out grouting reinforcement at the joint of the I-shaped steel plate 1, and then pour the first underground continuous wall through the pre-buried grouting pipe 8 underwater. For the wall, pull out the joint box after the pouring is completed;

(6) After the completion of the second phase of the adjacent tank section, first use the wall brusher to shovel to remove hard objects such as abrasive belts that have not fallen off, and then use the wall brusher wire brush to scrub the I-shaped end of the first phase of the tank from top to bottom Brush the steel plate up and down several times until there is no mud debris on the brush, and the accumulation at the bottom of the hole will no longer increase. After brushing the wall, the joint between the new and old concrete will be clean and dense;

(7) Hanging the joint box, hoisting and embedding the second wall reinforcement cage 10 in the wing plate of the I-shaped steel plate 1, pouring concrete underwater through the grouting pipe 8, and pulling out the joint box after the pouring is completed;

(8) The rest of the walls are poured sequentially according to the above steps until the last continuous wall is poured.

Claims (8)

1. The regional ground continuous wall connector antipriming 1. a kind of high rich water borders on the sea, it is characterised in that main structure includes i shaped steel Plate, diaphragm wall horizontal bar, the vertical main reinforcement of diaphragm wall, u u stirrup, galvanized iron sheet, press strip reinforcing bar, steel floral tube, Grouting Pipe, the first wall Width steel reinforcement cage, the second wall width steel reinforcement cage and sandbag；Diaphragm wall horizontal bar and the vertical main reinforcement mechanical connection of diaphragm wall, steel floral tube binding It is overlapped on the first wall width steel reinforcement cage；Galvanized iron sheet is mounted on the outside of I-shaped steel plate, galvanized iron sheet and press strip reinforcing bar spot welding Welding, I-steel and the first wall width steel reinforcement cage are welded to connect, fusion length 100mm；U u stirrup and diaphragm wall horizontal bar single side It is welded to connect, Grouting Pipe and the second wall width steel reinforcement cage binding overlap joint, the second wall width steel reinforcement cage is in lifting build-in in I-shaped steel plate In wing plate；Sandbag piles up I-shaped plate joint web outside, and lower raising degree is diaphram wall height.
2. 2. high rich water borders on the sea regional ground continuous wall connector antipriming according to claim 1, it is characterised in that the I-shaped Shape steel plate is welded by H profile steel plate, and the width on the edge of a wing is 400mm, the edge of a wing with a thickness of 10mm, the height of web is 160mm, web with a thickness of 10mm.
3. 3. high rich water borders on the sea regional ground continuous wall connector antipriming according to claim 1, it is characterised in that described continuous Wall horizontal bar and the vertical main reinforcement of diaphragm wall are according to requirement of engineering selection model and size.
4. 4. high rich water borders on the sea regional ground continuous wall connector antipriming according to claim 1, it is characterised in that the u shape hoop The model and spacing of muscle are identical as diaphragm wall horizontal bar, and the transfer angle of u u stirrup is 45 °, are hanging the second wall width steel reinforcement cage Better build-in is convenient for construction in I-steel wing plate when dress.
5. 5. high rich water borders on the sea regional ground continuous wall connector antipriming according to claim 1, it is characterised in that described zinc-plated The thickness of iron sheet is 0.3mm, width 500mm, and when strutting outward when slot section concrete pours, galvanized iron sheet prevents concrete from flowing into The slot section of adjacent non-grooving.
6. 6. high rich water borders on the sea regional ground continuous wall connector antipriming according to claim 1, it is characterised in that the press strip The model and size of reinforcing bar use C20, apart from i shaped steel edges of boards edge 100mm at and galvanized iron sheet spot-welded.
7. 7. high rich water borders on the sea regional ground continuous wall connector antipriming according to claim 1, it is characterised in that the spray of molten steel The diameter of pipe is A50, wall thickness 3mm, and highly suitable with the height of diaphram wall, two steel floral tubes are apart from i shaped steel It is connected at the horizontal 100mm of plate 1 with the binding of the first wall width steel reinforcement cage, the effect of steel floral tube is the excavation of foundation pit after water sealing structure forming Preceding carry out grouting reinforcing, it is ensured that the size of seam crossing water-stagnating effect, Grouting Pipe is identical as steel floral tube.
8. 8. high rich water borders on the sea regional ground continuous wall connector antipriming according to claim 1, it is characterised in that use the dress It sets and realizes that high rich water borders on the sea the detailed process of regional ground continuous wall connector sealing are as follows:

   (1) it pours and leads wall: levelling of the land → surveying and locating → excavation successively being carried out using existing construction technology and leads wall ditch and processing Roach → wall reinforcing bar, installation wall outboard template are led in binding → pours walls concrete → form removal and adds in cross-brace → slot The back-filling in layers earthwork；

   (2) slurrying: mud mix-design is carried out according to place geology, Groundwater Property and construction experience, makes configuration Mud index meets construction requirement, the process of mud configuration are as follows: after water is first added to mixing drum 1/3, starts pulper, then fixed While water-masuring box constantly adds water, bentonite in powder is added, after stirring 10min, CMC liquid is added and ground caustic continues to stir 10min i.e. Can stop stirring being put into new stock tank, wait stand extruding for 24 hours afterwards use；

   (3) I phase slot sections are excavated: will be first opened slot as test flume section, collected all kinds of parameters and data of trenching construction etc., try grooving Ground-connecting-wall routine grooving afterwards according to design drawing and leads wall and determines that I phase slot section excavates position, and chute forming machine carries out excavation operation；At Mud off is used when slot, is carried out an acceptance inspection according to related specifications to slot after grooving, is tiltedly rooted out after the completion of slot section with brush wall device The hard object not fallen off carries out cell wall cleaning；

   (4) the first wall width steel reinforcement cage fabrication of reinforcing cage: is made into rear and I-shaped steel plate by construction requirement using the prior art Welding, while installing galvanized iron sheet and press strip reinforcing bar；

   (5) grooving quality and mud index are examined after the clear trough end of step (3), connector case is hung after qualified, by the first width steel Muscle cage transfers to commitment positions, fills sandbag on the outside of I-shaped plate joint, prevents concrete from outflowing；It is continuous to reduce underground Wall wall Vertical Settlement and corresponding ground settlement carry out grouting and reinforcing with preset steel floral tube in i shaped steel plate connector, so Afterwards by the pre-buried first width diaphram wall of Grouting Pipe underwater casting, is risen after the completion of pouring and pull out connector case；

   (6) after the completion of II phase of adjacent slot section, the hard object not fallen off first tiltedly is rooted out with brush wall device, then with brush wall device wire brush from upper And I phase groove end I-shaped steel plate is scrubbed in lower segmentation, brush several times, is not further added by up to, without spare, bottom hole is deposited on brush up and down, Make New-old concrete joint completely closely knit after brush wall；

   (7) connector case is hung, by the second wall width reinforcing bar cage hoisting build-in in I-shaped steel plate wing plate, is poured under water by Grouting Pipe Concrete is built, is risen after the completion of pouring and pulls out connector case；

   (8) remaining wall width is successively poured according to above-mentioned steps, until last width diaphragm wall pours completion.