Process analysis of the Moxi earthquake-induced Lantianwan landslide in the Dadu River,China

Many large-scale landslides have occurred along the Dadu River, in particular in the middle section of the river, located on the eastern edge of the Qinghai–Tibet Plateau. The large-scale Lantianwan landslide was triggered by the 1786 Moxi earthquake (M_s = 7.75) at Luding, Sichuan province, China. Field investigations and 3D discrete element methods were used to examine the landslide formation mechanism and simulate landslide movement. The evolution of the landslide can be divided into four stages: initiation, high-speed motion, debris flow, and accumulation and river blocking. The results indicate that tension cracking and horizontal sliding were the geological origins of the Lantianwan landslide. The Moxi earthquake combined with the magnifying effect of the topography and the back slope formed deep-dip tensile structural planes in the Lantianwan slope, which triggered the landslide.

     

三维离散单元法及其在滑坡分析中的应用

介绍了三维离散单元法的基本原理,编制了相应的C语言程序,并对具体的滑坡实例进行了模拟,发现计算结果与已有研究成果较为一致,表明三维离散单元法是一种可以动态模拟山地滑坡行为的比较适宜的数值方法。     

某高速公路滑坡稳定性分析

针对稳定性分析在滑坡评价中的重要性,通过对滑坡工程地质条件、滑坡工程地质特征的叙述,从定性、定量两方面对滑坡区域、未滑区域进行稳定性分析,以防止产生边坡整体失稳。     

Factor analysis for the statistical modeling of earthquake-induced landslides

Earthquake-induced landslides are difficult to assess and predict owing to the inherent unpredictability of earthquakes. In most existing studies, the landslide potential is statistically assessed by collecting and analyzing the data of historical landslide events and earthquake observation records. Unlike rainfall-induced landslides, earthquake-induced landslides cannot be predicted in advance using real-time monitoring systems, and the development of the models for these landslides should instead depend on early earthquake warnings and estimations. Hence, in this study, factor analysis was performed and the frequency distribution method was employed to investigate the potential risk of the landslides caused by earthquakes. Factors such as the slope gradient, lithology (geology), aspect, and elevation were selected and classified as influential factors to facilitate the construction of a landslide database for the area of study.     

A rational layout of double-row stabilizing piles for large-scale landslide control

Bulletin of Engineering Geology and the Environment - Double rows of stabilizing piles can be applied to large-scale landslide control; however, the geometry of the layout can substantially affect...     

普翁特长隧道进口大型滑坡处治技术

介绍了厦蓉高速公路(贵州境)清镇至织金段普翁特长隧道进口大型滑坡的工程概况,通过对滑坡产生的原因分析,阐述了解滑坡处治施工方案,提出了具体的注意事项,为今后防范、处治隧道洞口滑坡有一定的借鉴意义。     

地震次生灾害区划初探

从地震灾害出发，重点讲述了地震次生灾害的危害与防治，提出次生灾害区划是防震减灾工作中的一个重要环节，并在自然灾害区划理论的基础上对地震次生灾害区划的内容与方法进行了简单的阐述。     

西南某堆积体滑坡成因机制及稳定性分析

根据西南某滑坡工程的地质条件,介绍了该滑坡的地形地貌及岩体结构特征,并分析了滑坡的形成机制,指出滑坡本身的特殊结构特征和良好的临空条件,以及易于汇水的特殊地形是诱发其活动的内因,强降雨作用下,滑体充分饱水产生的动水压力以及滑带软化,促使滑块产生平推式滑动。     

降雨条件下折线型滑面的大型滑坡稳定性离心模型试验

以大型土工离心机为技术依托,采用离心模型试验,研究开挖和降雨对滑面为折线型的大型滑坡变形破坏和稳定性的影响。试验中采用变形标志点、颗粒图像测速技术(PIV)和可承受高离心力的传感器,在获取坡体土压力、孔隙水压力和位移矢量场的基础上,综合分析开挖和降雨诱发大型滑坡变形破坏的特征及失稳模式。试验结果表明,在滑面形态变化大的部位开挖卸荷容易引起折线型滑面大型滑坡的局部复活;受开挖卸荷和降雨影响,滑坡后缘的开挖斜坡位移最大且最先失稳;受降雨的影响,滑坡前部位移较大,坡体表面变形破坏严重,开挖斜坡下部发育一条次级滑裂面,滑坡后缘和开挖平台前沿滑面坡度突变处各形成一条潜在主滑裂面。离心模型试验显示折线型滑面的滑坡受开挖和降雨的影响可表现出分级分块滑动的变形破坏特征。稳定性分析表明,降雨使折线型滑面的大型滑坡不同滑段稳定性系数不同程度降低,滑坡后缘、开挖斜坡和滑坡前缘处于不稳定状态。     

某滑坡稳定性分析

通过对浙江深圳镇高畈村高岭岗滑坡的工程地质条件、形成滑坡机制以及边坡稳定性分析,得出滑坡形成与水文工程地质、土的渗透性以及地形地貌特征有很大关系,通过稳定性反分析,提出抗剪强度指标,对于类似工程有借鉴意义。     

闽北某工程滑坡事故原因分析及经验教训

介绍了福建闽北某滑坡的工程概况及活动情况,分析了滑坡发生的原因,并提出了滑坡的应急处理措施,从该滑坡事故中总结了一些经验教训,指出勘察、设计、施工、监测四项工作是成功治理滑坡项目的关键,四者相辅相成,缺一不可。     

滑坡变形动态的自回归模型分析

1　前　　言 滑坡动态分析的主要方法有 :①通过绘制各测点的位移历时曲线及位移与主要影响因素的相关曲线 ,定性分析滑坡的动态发展趋势及影响因素的作用方式 ;②依据位移时序曲线预测滑坡的失稳时间 ,如斋藤法、灰色系统法、Ｖｅｒｈｕｌｓｔ模型法[1～ 3] 等 ;③对比不同部位的位移测量值 ,分析滑坡的变形破坏规律。这些方法在分析滑坡的变形动态特征方面取得了大量的成果 ,但滑坡的变形过程受多方面因素的影响 ,如环境条件的改变、局部的坍塌和次级滑面的形成等都会影响各测点的位移速率 ,使滑坡的位移时序曲线表现出波动性 ,从而使滑坡动态分析的难度增加。如在应用位移时序曲线预测滑坡的失稳时间时 ,就明显     

Dynamic centrifuge model tests and material point method analysis of the impact force of a sliding soil mass caused by earthquake-induced slope failure

Dynamic centrifuge model tests and associated analyses are carried out to develop a procedure for simulating the slope failure process during earthquakes and to evaluate the force of a sliding soil mass impacting a structure. This impact force is successfully measured in the dynamic centrifuge model tests using a slope height of 50 m in the prototype scale. The results of a pseudo-static limit equilibrium analysis, assuming a circular failure plane, show that a stability analysis can be an effective tool for evaluating the critical acceleration under which the slope failure starts, although it is not applicable for evaluating the runout distance or the impact force of the sliding soil mass to the structure. Therefore, an attempt is also made in this study to examine the applicability of empirical equations for evaluating the impact force by comparing the evaluated impact force using Hertz’s equation and an empirical equation based on fluid mechanics with the measured ones. The comparison reveals that these simple equations would not be able to estimate the impact force well, even though parameter setting is required for applying the equations. On the other hand, it is also found from a relevant analysis that the material point method (MPM) is an effective tool for simulating the failure behavior of a slope and for evaluating the impact force of a sliding soil mass induced by a slope failure.     

地震作用下混凝土梁桥连续倒塌过程分析

在地震中发生落梁可导致梁桥连续倒塌破坏.探究地震作用下混凝土梁桥连续倒塌的机理和规律,对于桥梁抗震设计与抗震加固、避免地震中桥梁倒塌破坏有着重要的意义.采用最新的材料本构、合理的结构数值模型及结构碰撞模型,利用有限元软件ABAQUS分析了一座四跨连续梁桥.分析结果很好地模拟了这座梁桥在地震作用下发生连续倒塌的全过程,落梁导致邻近桥墩破坏,其余桥墩及梁跨结构倾斜,引起远端落梁,桥墩接连破坏,最终桥梁全部倒塌.分析结果显示桥墩底部和中部系梁连接处的破坏较严重,应该进行针对性的抗震设计或加固.     

大型剪切连接件的分析

对现有剪切连接件形式进行了总结，并针对现有连接件的缺点，提出了大型剪切连接件的形式，最后通过有限元软件对栓钉连接件与大型剪切连接件进行比较分析，结果表明，大型剪切连接件的各方面性能均优于普通栓钉连接件。     

Estimation of large-scale mechanical properties of a large landslide on the basis of seismic results

Knowledge of large-scale mechanical properties is essential for estimating the stability of rock slopes being deformed by deep creep and especially for predicting a transition to rapid sliding. Standard geomechanical testing procedures may not result in significant values as the volume of the mass movements under consideration exceeds the volume of even the largest in situ tests by several orders of magnitude. Seismic measurements may help to estimate some of the relevant mechanical properties by direct correlation with the seismic velocities. However, not all parameters necessary for a stability analysis correlate closely with seismic velocities. An alternative approach could be the geomechanical modelling of the structures and properties of the creeping or sliding mass, as determined from seismic exploration. In this paper, we present an application of this approach to the giant landslide of Koefels. The development of the creeping rock mass, which represents the initial phase of the mass movement, has been successfully modelled by assuming a transition of the originally compact rock mass to “soft” rock, controlled by a Mohr–Coulomb and no tension yield criterion. Geomechanical parameters are determined by fitting the geomechanical model to the seismic results. An apparent angle of internal friction has been determined in the range 20–24°. These low values are compatible with the fact that a transition to rapid sliding took place in the past.     

孜拖西沟滑坡稳定性分析

根据孜拖西沟滑坡区的地质条件,介绍了滑坡的设计方案及标准,并对该滑坡的稳定性进行了分析,得知该滑坡按设计方案施工后在四种工况下均处于稳定状态,均能满足规范要求,说明设计方案合理有效。     

某滑坡稳定性分析与评价

以花栗树包滑坡Ⅲ的工程实践为例,通过整理相关勘查资料、岩土试验等资料,分析了该滑坡的基本情况、滑坡体的物质组成、结构特征及物理力学性质,探讨了滑坡的破坏机理,用极限平衡法对滑坡体的稳定性进行了计算,并对其在不同工况条件下的稳定性进行了分析、评价与预测。     

Regional back analysis of landslide events using TRIGRS model and rainfall threshold: an approach to estimate landslide hazard for Kodagu,India

Bulletin of Engineering Geology and the Environment - The mountain model developed by Fookes et al. (Eng Geol 21:1–152, 1985) comprised four terrain zones applicable to the Himalayan...     

某水电站工程右岸大型滑坡体处理施工技术

结合工程概况,针对水电站工程右岸发生的大型滑坡体,对削坡减载、坡面截水、排水、坡面挂网、喷锚支护、抗滑桩支挡等多种施工处理方法进行了详细介绍,以保证该水电站工程的安全使用,为今后处理类似工程的施工提供了借鉴。