What are the consequences of pouring the foundation cushion 3 cm higher?

It's only 3cm taller, which shouldn't be a big deal technically, or it's not a problem. If the supervision is serious, say hello to the supervision and design unit and the owner, as long as the bottom of the groove has been experienced, the strength and flatness of the cushion concrete meet the specifications and design requirements. Once it is detected, it is difficult to explain it compared to the truth.

If the supervision and design are not inspected, don't ask for trouble, and don't use the practice of reducing the thickness of the foundation plate to recover the elevation of the foundation.

The cushion is the intermediate layer of the reinforced concrete foundation and the foundation soil, the function is to make its surface smooth and convenient to bind the steel bar on it, and also play the role of protecting the foundation, all of which are plain concrete, without adding reinforcement. If there is a reinforcement, it cannot be called a cushion and should be regarded as a foundation slab.

Function] plays the role of leveling, isolation and transition.

1. It is convenient for the construction of the pay-off and the support of the foundation template to make a protective layer for the foundation reinforcement.

2.Ensure the effective position of the foundation bottom plate reinforcement and the protective layer is well controlled; Isolate the bottom reinforcement and soil from contamination.

3.It is convenient for the bottom surface of the foundation to be used as an anti-corrosion layer.

4.Leveling, by adjusting the thickness to make up for the error of earthwork excavation, so that the bottom plate is stressed in a plane, and the high-grade concrete of the foundation is not wasted.

Mattress is a method to solve the unevenness of the foundation in CFG composite foundation. For example, when the building is on a rocky foundation and clay on the other, it is solved by adding a bedding layer (graded sand) to the rocky foundation.

The cushion is a necessary condition for the formation of the pile composite foundation, and without the cushion, the soil between the piles can not give full play to its bearing capacity, and thus the pile composite foundation can not be formed;

The underlay refers to the structural layer located below the base layer. Its main function is water insulation, drainage, and anti-freezing to improve the working conditions of the base and soil foundation. Its materials can be sand, ceramite, mortar, concrete, etc.

Essentially, the cushion is the force transmission layer, and the cushion is the protective isolation layer.

Adjust the stress distribution of the load on the foundation to prevent stress concentration.

The cushion layer can ensure that the foundation always transmits a part of the load to the soil between the piles through the cushion layer, and adjusts the sharing of the load between the pile and the soil.

Say hello to the supervision and design unit and the owner, as long as the bottom of the groove has been experienced, the strength and flatness of the cushion concrete meet the specifications and design requirements, and it is only 3cm higher, which should not be a big problem from a technical point of view, or it is not a problem. If the supervisor is serious, he must say hello, and once the test is detected, it will be difficult to explain it. If the supervision and design are not checked, don't ask for trouble.

Remember, you should never reduce the thickness of the foundation plate to recover the elevation of the foundation, that is a big deal.

Of course, if the cushion strength is high, it can. Generally, the cushion under the concrete foundation is 100mm, which is not interesting when it is thick, uneven in force transmission, and the foundation reinforcement is easy to mix into the soil.