Do I need to vent after pouring? The role of the exhaust port of the gating system

If the raft foundation is very deep in the pouring process, it can be exhausted with an exhaust pipe, and the concrete that is poured in this way can reach the required density, and of course the collapse degree of concrete is also significantly reduced, but if the raft foundation is very shallow, it is not necessary to use the exhaust pipe.

Cement tank BAI truck operation procedures.

1. The cement tanker driver must first comply with the safety operation procedures of the loading truck driver. dao

2. Cement tanker drivers must study carefully and master the structure, performance, principle, driving, maintenance, maintenance and other technologies and safety operation procedures of cement tankers; Wear the prescribed protective equipment before work.

3. The driver of the cement tanker must do: before starting, check whether there are people on the tank, and it is strictly forbidden to drive.

4. Loading must be carried out in the following order:

1) Open the exhaust valve first;

2) Open the cover of the rear warehouse kiln and carry out the loading operation;

3) Close the back warehouse kiln cover;

4) Open the front warehouse kiln cover and carry out the loading operation;

5) Close the front warehouse kiln cover;

6) Close the exhaust valve;

7) Tighten the front and rear closure covers, and hang the front and rear safety hooks.

5. Before unloading, it is necessary to check the tightness of the air compressor, whether the transmission device is in good condition, and check whether the closed cover of each bin and the valves of each part are safe and reliable, so as to prepare for starting and unloading.

6. Under pressure of the tank, it is strictly forbidden to open or tighten the closed cover; It is strictly forbidden to dredge the dead plug at the bottom of the tank. 7. When opening or closing the closed cover, the human body must squat, operate about meters away from the side of the tank, and it is strictly forbidden to use afterburner devices to fasten the tank body, can cover screws, and fasten safety belts or safety ropes if necessary.

In general, there is no need for exhaust, if it is a floor pouring.

If the raft foundation is very deep in the pouring process, it can be exhausted with the exhaust style slow pipe, so that the concrete poured can reach the required density, of course, the collapse degree of the concrete is also poor and significantly reduced, but if the raft foundation is very shallow, it is not necessary to use the exhaust pipe when the raft foundation is very shallow.

Dude, I read the process you wrote, and I think that the main reason is that the hole is not cleaned thoroughly, and the sediment at the bottom of the hole is too thick. The phenomenon is explained as follows:

1. Why is the mud sprayed after the pump is dismantled? When cleaning the hole, the mud pump forcibly injects the high-pressure mud (but the specific gravity is small) into the bottom of the hole, but the mud in the hole is not completely replaced, the bottom of the hole and the conduit are newly injected mud, the specific gravity is small, and the middle of the hole is viscous high-density mud (which contains the sediment on the top, so the specific gravity of the mud you see in the upper part of the hole is greater), so when you remove the catheter halter, under the high pressure of the viscous mud in the middle, the mud will be sprayed out, and after the pressure is balanced, the spray will be stopped.

2. Why does the mud spray out during the pouring of concrete? This is the same as the previous one. The concrete inside the conduit sinks because the pressure of the fluid (slurry or concrete) inside the conduit is greater than the pressure of the mud inside the hole outside the conduit.

However, because the specific gravity of the mud in the middle and bottom of the hole is too large, the mud distribution of different specific gravity in the conduit is basically the same as the outside of the pipe, and when the bottom is sealed, the balance of the mud distribution is broken by the high pressure of the concrete in the aggregate hopper, but when the top surface of the concrete sinks, the pressure becomes smaller, and the pressure outside the pipe is **, resulting in the mud spraying.

Summary and suggestions: 1. Clean the hole as much as possible, replace the mud, and reduce the sediment at the bottom of the hole. 2. Appropriately lower the water head in the hole and raise the upper mouth of the catheter as much as possible to increase the fluid pressure in the catheter. 3. The ground pump or automobile pump is directly connected with the conduit, and the guide pipe is pressurized and poured concrete.

The catheter head is not tightly closed, and the concrete slump is small, resulting in insufficient injection and insufficient continuous pressure.

Have you counted the back cover concrete, is it enough?

And have you calculated the loss of the bottom concrete, the tanker is clean, the conduit is clean, how much cement mortar to adsorb away, the importance of the bottom concrete is well understood, the conclusion, the concrete slump may not be enough, and the workability is impressed.

After pouring and vibrating, the concrete can gradually condense and harden, mainly because of the result of cement hydration, and hydration requires appropriate temperature and humidity conditions, so in order to ensure that the concrete has suitable hardening conditions, so that its strength continues to grow, the concrete must be cured. Key points of concrete curing:

First, the starting concrete curing time; 2. Timely and adequate wet curing; 3. Secondary plastering.

How to maintain the concrete after pouring?

Which hole ??? Running through the floor slab is water and electricity control, wiring.

The underground chisel that does not penetrate is called chiseling, and the place where the stubble is connected must be treated in this way, in order to connect the two layers more firmly.

When pouring, the liquid enters from the top, repelling the air inside the mold and filling the mold. If there is no exhaust port, the air inside will only have two fates: either it will not run out of the mind and will be compressed to form cavitation and source state with waste, or it will be sprayed back from the hydrothermal inlet, which will interfere with the casting and cause uneven material, and even cause hail and become a safety accident.

The exhaust port is all about providing a smooth outlet for the remaining air (or other fluid) inside.