2、 Bottom slab concrete pouring method 1.
The cement slurry on the surface of mass concrete pouring is thick.
Generally, the layer height is 1.25 times of the length of the acting part of the plug-in vibrator, which is no more than 500mm, and the layer thickness of the plate vibrator is 200mm.
The formwork at the lower part of the large opening shall be opened and vibrated.
The bleeding discharge when the concrete is poured to the top is shown in the attached figure.
The insertion points shall be evenly arranged, moved point by point and carried out in sequence without omission, so as to achieve uniform vibration.
5.
The pouring method of forming a slope by the natural flow of concrete avoids the frequent disassembly, flushing and extension of the conveying pipe, so as to improve the efficiency of pumping concrete and ensure that the gap time between the upper and lower layers of concrete does not exceed 1.5 hours.
During vibration, the vibrator shall be more than 300mm away from the hole edge and vibrated from both sides at the same time to prevent deformation of the hole.
6.
2.
The concrete shall be vibrated evenly and densely, especially in the parts with small wall thickness, staggered reinforcement and connection of door and window opening structure, and dense reinforcement Φ 25 vibrating rod, used for other wall beam parts Φ 50 vibrating rod, considering that the concrete at the lower wall position of the wall and window opening cannot be vibrated directly after the formwork is sealed, the lower opening of the window opening can be reserved as a flexible opening in advance, and the formwork can be sealed and reinforced after the concrete is poured to this position and vibrated and compacted.
I.
Generally, more than 2 hours shall be treated as construction joints.
When pouring vertical structure concrete, if the pouring height exceeds 3M, tumbling barrel, conduit, chute or opening sub hole on the side of the formwork shall be adopted.
As shown in the attached figure.
When pouring more than 500 thick concrete base plate, the method of “section and layer, inclined pouring, one slope, thin-layer pouring and tamping, advancing in sequence and reaching the top at one time” shall be adopted, as shown in the attached figure.
4.
If any problem is found, the pouring shall be stopped immediately, and the repair shall be completed before the initial setting of the poured concrete.
The method of continuous pouring in sections and layers is adopted.
5.
Before pouring, the formwork shall be watered and wetted, and the cleaning opening of wall and column formwork shall be closed after removing sundries and ponding.
The pouring direction of Sections I, II and III on the second floor of the basement is pushed from 7 / OA to 1 / OA axis; The pouring direction of sections IV, V and VI is pushed from 1 / OA axis to d axis.
7.
Before column and wall pouring, or at the joint of newly poured concrete and lower concrete, 50mm thick cement mortar with the same proportion as the concrete shall be evenly poured on the bottom surface.
During mechanical vibration, it shall be gradually pushed towards the construction joint, and the compaction of the construction joint shall be strengthened to make it closely combined.
The moving distance shall not be greater than 1.5 times of the action radius of the vibrating rod (generally 300 ~ 400mm).
2.
The moving distance of the plate vibrator shall ensure that the plate of the vibrator covers the edge of the vibrated part.
If intermission is necessary, the intermission time shall be shortened as far as possible.
General requirements for pouring 1.
It is strictly forbidden to step on the reinforcement directly.
In case of displacement and deformation, it shall be handled in time to ensure the quality of concrete.
7.
3.
After about 12 hours, it shall be covered with plastic cloth and gunny bag, and fully watered and moist for maintenance.
Concreting shall be carried out continuously.
Before pouring concrete, horse stool, pedestrian passage and operation platform shall be set.
The column wall concrete shall be poured and vibrated in layers, and the pouring thickness of each layer shall be controlled at about 500mm.
When pouring the wall opening, the concrete height on both sides of the opening shall be roughly the same.
During the pouring of mass concrete, the surface bleeding adopts vacuum water absorption.
The person who breaks the passage shall be removed.
Before initial setting, it shall be rolled with an iron roller for several times, and then leveled and compacted with a wooden trowel to close the water collection crack.
When pouring concrete at the post pouring belt, a layer of cement mortar shall be plastered on the surface of the construction joint first.
3.
The pouring direction of the three transfer pumps.
The concrete shall not be placed directly close to the construction joint.
3、 Column and wall concrete pouring 1.
The concrete pouring is mainly transported to the basement by two concrete transfer pumps, supported by tower crane and supplied by commercial concrete.
2.
The secondary layer of concrete shall be poured before the initial setting of the previous layer of concrete.
When pouring concrete, special personnel shall be assigned to watch the formwork, support, reinforcement, embedding and reservation.
If it is found that the surface bleeding is too much, the water cement ratio shall be adjusted in time.
After about 2 ~ 4 hours, it shall be scraped with a long scraper according to the elevation.
If it exceeds 2m, measures of adding tumbling barrel must be taken.
The mortar shall be poured into the formwork with a shovel instead of a hopper.
When using the plug-in vibrator, it shall be inserted quickly and pulled out slowly.
The concrete shall be poured in sections and layers, and the pouring height of each layer shall be determined according to the structural characteristics and the density of reinforcement.
According to the actual situation that the concrete naturally forms a slope, two vibrators are arranged in front and back of each pouring belt, and the former is arranged at the unloading point to mainly solve the tamping of the upper concrete; The latter is arranged at the concrete slope toe to ensure the compactness of the lower concrete.
3.
The concrete of structural column shall be poured in layers, and the thickness of each layer shall not exceed 300mm.
The free falling height of concrete falling from the bucket mouth shall not exceed 2m.
When pouring beam slab concrete, the joint area of wall and column shall be constructed according to high-strength concrete, and the interface is 500 beside the wall and column, as shown in the figure..
The pouring direction of Sections I, II and III on the first floor of the basement is pushed from 7 / OA to 1 / OA axis; The pouring direction of sections IV, V and VI is pushed from 1 / OA axis to U axis.
4.
With the advance of concrete pouring, the vibrator follows up accordingly to ensure the quality of concrete at the whole height.
After concrete pouring, it shall be handled carefully.
When pouring concrete, special personnel shall be assigned to regularly observe the displacement, deformation or blockage of formwork reinforcement, reserved holes, embedded parts and dowel bars.
6.
5.
Before concrete pouring, accurately grasp the weather conditions, avoid rainy days, and try to arrange the pouring of concrete at the bottom plate cylinder at night, so as to reduce the internal hydration heat of concrete at thicker places.
4.
The maximum time of intermission shall be determined according to all types of cement and initial setting conditions of concrete.
When vibrating the upper layer, it shall be inserted into the lower concrete surface for 50mm to eliminate the joint between the two layers.
The concrete blanking points shall be arranged in a decentralized manner, and the cyclic advance shall be carried out continuously.
