The vane shear rheometer was used to study the rheological properties of the water-bearing sand layer. The test curves including shear resistance,water content,pore water pressure and strain velocity were obtained. The results show that the rheological curves of the sand layer appear obvious different phases,stable rheological stage and accelerated rheological stage,with the water content increasing. The former stage experiences the elastic deformation, initial and non-accelerated rheological processes. When shear resistance achieves the yield resistance strength,the sand layer entered the accelerated rheological stage,and the strain velocity increases quickly. Based on the fitted curves of accelerated rheological stage,the relations between loading shear resistance,yield shear strength and stress velocity were obtained. The analysis indicate that the resistance strength of dry sand comes from the friction between particles,when the water content increases the particles are surrounded by the water which decreases the acting forces between the particles. Therefore,the rheological properties change obviously. The yield resistance strength is the critical parameter to reflect the change process which is connected with the loading shear stress and water content.

云南省通过综合物探手段开展滑坡体地质性状识别,为滑坡体监测布置及分析评价提供数据和依据,运用在线及移动式监测技术(必要时采用综合物探方法进行快速探测)实时掌握滑坡体工作性状.综合应用物探及监测成果,对滑坡体进行快速准确、高效低成本的安全评价和分级预警.

小三峡电站拦河坝高23.5m,坝轴线长298.5m,为混凝土重力坝和钢筋混凝土面板堆石坝.水库正常蓄水位1103m,总库容1524万m3,回水长度7.98km,调节库容215.98万m3.电站具有日调节能力,装机容量30MW,电站水头13.5m,设计引用流量244.29m3/s,多年平均发电量14662.98万kWh,年利用小时数5256h,电站总投资2亿元.本文对该电站工程保险的风险进行简要评估.

通过干热河谷地区水土保持的一些经验,因地制宜进行植物措施的配置和设计,并根据植物的生物学特性,科学合理地选择和搭配树种,实现水土保持绿化景观效应与周围环境的和谐统一,取得生态和经济的双重效益。