碾压堆石体成拱机理分析

碾压堆石体作为一种重要筑坝材料，其成拱效应始终是碾压堆石坝安全问题的焦点之一。碾压堆石体随堆积形式和施工工艺的差异而具有不同的工程特性，其破坏服从Coulomb-Mohr破坏准则。针对碾压堆石体的特殊施工工艺对涪陵城区移民迁建防护工程的碾压堆石体民拱机理进行了理论研究，并用FLAC有限差分程序对成拱机理进行了数值分析，结果表明碾压堆石体在一段时间的沉降之后的确可形成压力拱，压力拱正上方的土压力值小于两侧土压力，并承担部分上覆土层的自重及外加荷载。

Analyisis of Arching Mechanism in Compacted Rockfill

As the main material in constructing dams,arching mechanism in compacted rockfill is aways the focus of safety problem in compacted rockfiu dams. Compacted rockfill has different engineering characteristics according to stack forms and constructing techniques,and the failure of compacted rockfill conforms to Coulomb_Mohr criterion.Compacted rockfill is the main material in protecting embankment for the migration movement in Fuling city zone.The arching action is theoretically studied and numercally modelled especially for constructing techniques.It is found out that the arching action begins and numerically of settlement and burdens part of load and deadweight of upper soil.Earth pressure applied to the arch is smaller than the weight of overburden.