Manhole cover is used to cover up the road or deep well at home. It is generally divided into round and square to prevent people or things from falling. In urban road administration, round manhole cover is generally used, because the round well cover is not easy to tilt, which can better protect the safety of pedestrians and vehicles. It is mainly considered that the length of each diameter of the round well cover passing through its center is the same, so that if the well cover is rolled up by the passing vehicle, its diameter will be slightly wider than the hole below no matter how it is rolled up, and the well cover will not fall into the wellhead.
Control points and safety performance of compound manhole cover
In order to ensure the stability and safety of the composite well cover, it is necessary to control the factors in all aspects and strictly follow the design drawings. It is generally required to control the following places.
1. The removal of the ditch body formwork shall be carried out slowly to avoid damaging the edges and corners of the side ditch. After the removal of the formwork, the felt cloth or geotextile shall be used to cover and maintain the health in time. In order to ensure normal use, attention should be paid to the installation quality, not only the accuracy of the size, but also the convenience of opening, cleanness and beauty.
2. When installing the composite cover pouring concrete side ditch, the vibration shall be uniform and not be vibrated at the same place for a long time; in addition, pay attention to clean and wash the concrete missed on the road surface, and do not pollute the road surface.
3. It is required that the plane position, elevation and flow direction of the side ditch shall be strictly controlled in accordance with the construction design drawings during the construction of the soil side ditch.
4. It shall be clearly specified that mortar shall be used for leveling on the top of concrete side ditch wall during installation. In addition, the top surface of cover plate shall be roughened during the construction of pavement layer of level crossing. After the construction is completed, it shall be covered and cured in time, and it shall be released after the concrete strength reaches 80%.