After the concrete pouring on the side of the post cast strip is completed, chisel the concrete at the post cast strip and intercept it with steel wire mesh to ensure the exposed width of water stop steel plate → wash the construction joints on both sides of the post cast strip with high-pressure water gun, clean the debris from the reserved cleaning opening of the bottom formwork, and paint cement slurry on the joint surface → restore the reinforcement in the post cast strip and conduct concealed acceptance.
3.
Three official account numbers are recommended for attention..
The cover plate is poured with c30p6 finished concrete and vibrated tightly.
Process flow 1.
The edge of the cover plate is an internal corner fillet → bind the reinforcement mesh of the protective layer, and the mesh reinforcement adopts φ 4@300×300 → pour the waterproof protective layer, and the rigid layer shall be poured with 70mm thick C20 fine aggregate concrete.
The process is applicable to a wide range, easy to master installation and use, and easy to popularize and use.
The size of horizontal prefabricated cover plate is 1200x800x100mm (thickness), and the bottom reinforcement mesh of cover plate: φ 8@200mm , two-way arrangement.
Various processes are interspersed several months in advance to realize rapid construction.
This paper takes the project of the third company of China Construction Fifth Bureau as an example to learn and apply the new process together! Process principle: the reinforcement ratio and thickness of precast cover plate are designed through different post cast strip width and soil covering thickness.
Design and fabrication of cover plate and pouring pipe.
Install the prefabricated cover plate with waterproof cement mortar base slurry, install the prefabricated cover plate, plaster the R angle with waterproof cement mortar at the edge of the cover plate, and fill the joint of the cover plate with waterproof mortar.
In case of pouring pipe, turn up to 5cm inside the pipe.
It can realize water cut-off of basement and early backfilling of general layout.
2.
After reaching the age, pour self compacting micro expansion impermeable concrete, block the local pouring conditions of closing settlement post pouring belt, pour self compacting micro expansion impermeable concrete from the reserved pouring opening of precast cover plate, and vibrate and compact with immersion vibrator.
Chisel the post cast strip.
After the settlement post cast strip meets the sealing conditions, the self compacting concrete shall be poured, and finally the edge and mouth closing treatment shall be carried out.
Tongue and groove shall be set between the cover plates to ensure the tight connection of the cover plates.
Both sides of the post cast strip are chiseled and cleaned in advance, and the bottom formwork of the post cast strip is cleaned and reinforced in advance.
The pouring opening spacing is set according to the thickness of the structure to be poured and the density of reinforcement.
3.
The lifting ring shall be bound with the reinforcement mesh during installation.
After the laying of the cover plate is completed, the water interception and waterproof construction shall be carried out, the water cut-off of the basement and the closure of the roof can be completed, and the working face can be handed over to the follow-up work.
Precast cover plate waterproof construction binding protective layer reinforcement mesh pouring waterproof protective layer # 6.
This process “prefabrication and advance water stop sealing of post cast strip to realize decorative water cut-off”, which is applicable to the closed construction of post cast strip for settlement of all high-rise and super high-rise buildings.
The follow-up work can be inserted faster, shorten the construction period and reduce the project cost.
After the settlement is stable, the self compacting micro expansion impermeable concrete is used to seal the post cast strip structure.
The bottom formwork, side formwork and support of the post cast strip shall be closed and the cleaning opening shall be reserved → the bottom formwork at the post cast strip position shall be reinforced and the side formwork shall be restored.
A 3mm thick water stop wing ring is set at 30mm at the bottom of the steel sleeve, and the length of the steel sleeve is 300mm.
The process is more convenient to close the post pouring belt after settlement, and the component is easy to install.
A galvanized steel sleeve with a diameter of 300mm is reserved for the cover plate.
Waterproof construction and treatment of cover plate base of post cast strip of protective layer → construction of waterproof additional layer at the cover plate → waterproof construction at the cover plate is the same as that of basement roof.
After the concrete pouring of the post cast strip is completed, the closure shall be blocked and the steel sleeve shall be cut off.
Process features 1.
The use of prefabricated cover plate is safer and more reliable, with lower labor intensity and less demand for operators.
Installation of prefabricated cover plate 5.
4.
Bottom formwork reinforcement Figure 4.
Method of horizontal precast slab 2.
The waterproof and surface construction can be carried out in advance, so as to provide a working surface for subsequent processes in time.
Only the prefabricated reinforced concrete cover plate with cast steel pipe needs to be installed at the post cast strip position, and the waterproof construction is carried out.
In this process, the sealing construction of the post cast strip is simple.
An 8mm diameter round steel lifting ring is set at 200mm from the top of the cover plate to the end of the cover plate for transportation and hoisting of the cover plate.
