报告题目：Advancing the Predictability of Infiltration-induced Landslides 　

报告人：Ning Lu, Colorado School of Mines，Department of Civil and Environmental Engineering, Golden, CO 80401, USA

报告时间：2014年3月11日(周二)下午3:00　　　

报告地点：信阳师范学院贤林讲坛

报告人简介：Ning Lu (卢宁)，出生于福建福州。1991年毕业于美国约翰·霍普金斯大学获土木工程博士学位。美国地质学会会士、美国土木工程学会会士，科罗拉多矿业大学土木与环境工程系教授，过去10年主要研究课题为斜坡水文学与稳定性。卢教授是《非饱和土力学》(美国John Wiley & Sons，2004)和《斜坡水文与稳定》(英国Cambridge University Press， 2013) 的第一作者，在世界知名期刊上发表了大量的，高引用率的有关变非饱和多孔介质统一有效应力的论文。因为开创性地定义了变饱和土的吸应力特征函数概念，他先后获得了美国土木工程学会Norman Medal奖和Cores Medal奖。

卢教授主导研制的自动相对湿度控制(Auto-RH)土水特征曲线系统  (http://www.epccn.com/product/autorh.html)和瞬时释放和吸入法(TRIM)土水特征曲线测试系统(http://www.epccn.com/product/trim.html)是目前世界上独一无二的快速测试各种土壤土水特征曲线和渗透系数函数的试验装置。

报告题目：Advancing the Predictability of Infiltration-induced Landslides

报告摘要：Slope-stability analyses are mostly conducted by identifying or assuming a potential failure surface and assessing the factor of safety (FS) of that surface. This approach of assigning a single FS to a potentially unstable slope provides little insight on where the failure initiates or ultimate geometry and location of a landslide rupture surface. A unified effective stress framework for variably saturated porous media and a scalar field of factor of safety are employed to account for effective stress variations under rainfall conditions. The scalar field of FS is based on the concept of the Coulomb stress and the shift in the state of stress towards failure that results from rainfall infiltration. The FS at each point within a hillslope is called the local factor of safety (LFS) and is defined as the ratio of the potential Coulomb stress to the current Coulomb under the Mohr-Coulomb criterion. Comparative assessment with limit-equilibrium and hybrid finite-element limit equilibrium methods show that the proposed LFS is consistent with these approaches and yields additional insight into the geometry and location of the potential failure surface and how instability may initiate and evolve with changes in pore-water conditions. Quantitative assessments demonstrate that the LFS has the potential to overcome several major limitations in the classical FS methodologies such as the inherent underestimation of slope instability. Comparison with infinite-slope methods, including a recent extension to variably saturated conditions, shows further enhancement in assessing shallow landslide occurrence using the LFS methodology. The LFS provides a new means to quantify the potential instability zones in hillslopes under variably saturated conditions using stress field based methods.