What is the plan for concrete retaining wall construction?

The construction plan of the concrete retaining wall is: the design type of the reinforced concrete retaining wall is cantilever retaining wall and buttress retaining wall. When the height of the retaining wall is less than 4.5m, Use cantilever retaining walls. When the wall height of the retaining wall is greater than 4.5, use buttress retaining walls. The horizontal spacing of the weep holes of the retaining wall is 2m and the longitudinal spacing is 3m. The wall height of the retaining wall is greater than A drainage hole is provided at 3m. When the wall height H ≤ 3.5m, there is no chamfering; behind the wall, 1:4 lime soil is backfilled and compacted in layers, with a compaction degree of ≥95 (light compaction), and the foundation is 3:7 lime soil with a compaction degree of ≥95 (heavy compaction) ); The settlement joints of the retaining wall are divided into sections according to the longitudinal section design. The width of the seam is 2cm, and 2cm on the back side of the wall is embedded with rubber asphalt waterproof sealant, and the remainder is filled with L-600 low-foam polyethylene foam; the back of the retaining wall is sprayed first HUG-3 waterproof material is sprayed twice, and after drying, spray HUT-1 waterproof material twice. Anti-collision guardrails and railings are set up on the top of the retaining wall. During construction, attention should be paid to the setting of the embedded steel bars of the anti-collision guardrail. The construction of the retaining wall should be strictly carried out according to the related layout to ensure that the wall position, elevation and strength meet the requirements. The retaining wall in this section is a cantilever retaining wall.

1. Excavation of the foundation trench: The excavation of the foundation trench for this project is carried out manually with an excavator. The foundation excavation is carried out in sections in conjunction with the wall construction. First, measure and set out the excavation center line and side lines, starting point and end point, set up stakes, indicate the elevation and excavation depth, and use a 1m3 backhoe excavator to excavate. The earth is loaded into trucks and the spoil is transported out. During the construction process, drainage ditches and water collection resistors should be set up according to actual needs for construction drainage to ensure that the working surface is dry and the base is not flooded.

2. Foundation treatment: When a silt layer or soft soil layer is found during foundation excavation, soil replacement needs to be carried out, and construction can only be carried out after approval by the supervision engineer.

3. Gravel cushion construction: Cast-in-situ reinforced concrete retaining wall according to the design drawings. A 20 cm thick gravel cushion is laid on the base, and the foundation soil is rammed into the foundation with a tamping machine. Concrete retaining wall construction plan Concrete retaining wall construction plan. to increase the base friction coefficient. The foundation cushion of the concrete retaining wall is C10 concrete cushion 10 cm thick.

4. Installation of steel bars:

For the cast-in-place steel bar foundation, the foundation steel bars are installed first, and the vertical steel bars of the wall are pre-prepared. After the foundation is poured with concrete and the concrete reaches 2.5Mpa, proceed Installation of wall steel bars.

The foundation steel bars of the prefabricated reinforced concrete retaining wall are installed in two steps. The bottom layer of steel bars is installed first, and the foundation reaches a certain strength. After the prefabricated wall is installed, the second level of foundation steel bars is installed.

5. Cast-in-place concrete foundation: According to the length of the retaining wall, the entire section is poured at one time. Measure and lay out the lines on the cleaned cushion surface, and formulate the poured concrete retaining wall construction plan article. The concrete retaining wall construction plan comes from /article/wk-78500000741839.html, please keep this link for reprinting! .

6. Cast-in-situ wall concrete: The joint surface of the cast-in-situ reinforced concrete retaining wall and the foundation should be treated as a construction joint, that is, the loose part of the concrete and floating slurry should be chiseled out first. , and clean it with water, then erect the wall formwork. When pouring the concrete, first brush a layer of cement slurry on the joint surface or pad a layer of 2-3 cm thick 1:2 cement mortar before pouring the wall concrete.

The wall formwork is assembled with seven smooth plywood panels. The vertical beams are 8×10cm with a spacing of 40cm. Steel pipes are used as fences. 8×10cm wooden beams are used as diagonal braces for support. The side moldings are The ф16 bolts are pulled and positioned, and the distance between the bolts is 80cm. Hard plastic pipes with an inner diameter of 20-25cm can be used for bolt perforation. When removing the formwork, pull out the bolts and plug the bolt holes with 1:2 cement mortar. The wall formwork should be Depending on the height, there are one method of mold erection to the top and two methods of mold erection. Generally, if the height is less than 4 meters, it can be divided into one mold erection. If the height exceeds 4 meters, it can be divided into two methods, or it can be one time erection. When the concrete drop height is greater than 2.0m, string tubes should be used to transport the concrete into the mold, or manual ash separation should be used to avoid concrete segregation.

The concrete is processed by the concrete mixing station and transported to the site by a concrete transport vehicle. A platform is set up on the top of the wall and the concrete is lifted to the platform by a crane for pouring. The concrete pouring is carried out evenly in layers starting from the lower part. The layer thickness is generally 30cm. Use a plug-in vibrator to vibrate. The moving distance of the vibrator rod should not exceed 1.5 times its radius of action, and should be kept 5-10cm away from the side mold to avoid leakage or over-vibration. During the concrete pouring process, if there is too much water bleeding on the surface, the water should be drained away in time or measures should be taken to reduce water layer by layer to avoid loose tops. After pouring to the top surface, the surface should be wiped in time, and then wiped again after setting the slurry. The surface is smooth

During the concrete pouring process, carpenters, steel workers, electricians and test workers should be dispatched to the site to be on duty, and problems found should be dealt with promptly. Concrete retaining wall construction plan highway cost engineer.

Concrete strength parts should be made randomly at the on-site mixing site or pouring site, and no less than 2 sets of test pieces (3 pieces per set) should be made in each work shift.

After the concrete is poured and grouted, water should be sprinkled and cured in time. The curing time should be at least 7 days. The wall side formwork can generally be removed within 24 hours at room temperature. Special care must be taken when removing the formwork. Don't damage the wall.

7. Treatment of expansion joints, settlement joints and weep holes

The expansion joints and settlement joints of cast-in-place reinforced concrete retaining walls are 2cm wide (the joints are sandwiched by 2cm during construction) Centimeter-thick foam board or wooden board, pull out the wooden board or foam board after construction) and fill the inner, outer and top sides of the wall with asphalt fiber from the top to the base, 15cm deep.

The drainage hole of the retaining wall is a ф10cm hard hollow pipe. 50×50×50cm gravel is laid around the entrance of the drainage hole. The gravel is wrapped with geotextile. 30cm is laid at the bottom of the entrance of the lower drainage hole. The thick clay layer has been compacted.