Slab culvert is simple in structure, but it requires high construction technology. In site construction, the key to the success or failure of slab culvert construction is often a working procedure. For example, if the bearing capacity of a foundation pit can not meet the design requirements, the subsequent process construction will be carried out. In this way, the culvert construction is completed, but the culvert structure is damaged due to foundation settlement, or the irrigation and drainage of farmland is affected due to foundation settlement and pore size reduction.
Generally, there are five processes in the construction of slab culvert: foundation pit excavation, foundation construction, abutment construction, slab construction, import and export and culvert bottom treatment.
Hardness requirements, a certain surface hardness can prevent burrs from appearing on the upper surface of the borehole, but too hard will wear the drill bit; Its composition does not contain resin, otherwise it will be greasy and dirty when drilling; It is required to have high thermal conductivity, which can quickly take away the heat generated during drilling and reduce the bit temperature;
It is necessary to have a certain rigidity to prevent the vibration of the plate when drilling, and to have a certain elasticity. As soon as the drill bit touches it, it will deform immediately, so that the drill bit can accurately aim at the position to be drilled and ensure the accurate drilling position. Thickness and tolerance requirements, uneven surface will have an impact on drilling.
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