配筋超高性能混凝土井盖试验及现场使用性能测试

Experimental and field performance research of reinforced ultra-high performance concrete manhole covers

对7个井字肋和1个十字肋的配筋超高性能混凝土(UHPC)井盖进行承载能力试验和有限元分析,试验参数为井盖结构形式和钢纤维掺量.试验结果表明,井字肋UHPC井盖的极限承载力、结构刚度和延性均优于十字肋UHPC井盖;井字肋UHPC井盖可满足钢纤维混凝土检查井盖对C250级井盖的强度要求.其次,对井字肋UHPC井盖在重交通等级作用下开展现场使用性能测试,表明UHPC井盖在使用过程中产生噪音和跳动均较小,具有良好的抗振动和抗车辆冲击性能;其最大裂缝宽度不超过0.2 mm,符合钢纤维混凝土检查井盖的规定.

In this study,experimental investigations and finite element analysis on 7 well-shaped and 1 cross-ribbed ultra-high performance concrete(UHPC)manhole covers were carried out,taking structural type and steel fiber volume fraction as the key parameters.The results show that the wellshaped UHPC manhole cover has larger load carrying capacity,and better ductility and stiffness than that of the cross-ribbed covers.In addition,the well-shaped manhole cover could meet the requirements of the cover of Class C250 in the standard of“steel fiber reinforced concrete manhole cover”.The field experimental research on the performance of UHPC covers was also conducted under the action of heavy traffic grade.The UHPC cover has good vibration and shock resistance which could weaken the vibration and noise in the using process.The crack width of UHPC cover was no more than 0.2 mm,which can meet the requirements of above the standard.