Thickness of manhole cover and the load-bearing

Is there any relationship between the thickness of manhole cover and the load-bearing?

　　 For a long time, the safety of manhole covers has been the focus of attention. The impact of the incident caused by the loss or damage of the manhole cover cannot be ignored. With the development of economy, there are more and more types of manhole covers, and composite manhole covers are one of them. Moreover, the specifications of the load-bearing manhole cover will vary according to the usage in different regions. So, what is the relationship between the thickness of the composite manhole cover and the load-bearing grade? It must be related to this matter.

　　 Unlike traditional cast iron manhole covers, composite manhole covers are mostly made of resin, fiber and other materials, which have no recycling value and completely avoid the theft of iron manhole covers. There are fiber cement concrete manhole covers, resin manhole covers, etc., which can be used for green belts, sidewalks, driveways, etc. The thickness of the composite manhole covers are also different. Compound manhole covers can be divided into square manhole covers and round manhole covers according to their shapes. Round manhole covers are generally used on elastic roads, because they are not easy to tilt and can better protect the safety of pedestrians and vehicles. In rural areas and cable wells, squares are generally used to better prevent rainwater and other liquids from entering.

　　 In addition, the thickness of the load-bearing manhole cover can be divided into 3cm, 4cm, 5cm and 7cm, which are common thicknesses. In areas where motor vehicles are not allowed to enter, such as green belts and sidewalks, a 3 cm thick manhole cover is generally used. Non-motor vehicle lanes, parking lots, and underground parking lots generally use 3-4cm thick manhole covers. 4-5cm thick manhole covers are generally used in residential areas, back streets and alleys, and areas where there are only light vehicles or small cars. In areas such as urban arterial roads, highways, high-grade highways, expressways, etc., manhole covers with a thickness of 5-7 cm are generally used. In areas such as gas stations, freight stations, docks, airports, 7 cm thick manhole covers are generally used.

　　 In summary, 3-4cm manhole covers are generally used in low-load areas, and 5-7cm thick manhole covers are generally used in high-load areas. In fact, not only the thickness of the composite manhole cover has an influence on the bearing capacity, but the material and forming time of the manhole cover also have an influence on the bearing capacity. The carrying capacity of SMC manhole covers is better than that of BMC manhole covers, and the carrying capacity of SMC manhole covers is affected by the length of the press forming time.