由于構築物沉降速度隨時间而减缓直至中止沉降,因而在道路投入運用较長時间後井週沥青毁壞并不是窨井下沉形成的,應爲井蓋在長期荷载作用下,不時發作弹性變形,使井週沥青在井蓋邊框重復作用下變形至極限形成疲倦毁壞,斷裂破损。鼕季呈现狀况较多,常在20CM左右範围内呈现裂痕,且井盏有明顯下沉。
Today's urban road with subsidence appeared more and more covers, manhole covers sinking is what circumstance, how can we solve the manhole cover down this problem?
Installation problem:
1, manhole covers, and wall structure design scale is low, the structure layer without reinforcement to strengthen design, etc.
2, in road motorway pipeline project scope planning layout is not reasonable.
3, large quantities of heavy overloading vehicles in urban traffic, lacking the ability to choose the product load manhole covers, causing damage.
4, small tolerance of shaft wall, than can withstand the weight of manhole covers and vehicle load, settlement.
5, covers the base reinforcement construction, manhole covers and the road is rough, rupture of the framework and even covers life reduce breakage.
6, covers installation, construction personnel is not required to install according to the rules.
Due to the structure of sedimentation velocity with time and slow and eventually stop settlement, therefore in the asphalt road well put into use after a long time weeks damage is not caused by CMC sinking, should be well cover under long-term load, continuous elastic deformation occurs, keep well asphalt in the manhole cover frame under the action of repeated deformation to extreme fatigue damage, fracture damage. The appearance is more, the winter often cracks within 20 cm, and Wells have obvious subsidence.