Historical and Geological Evidence for Seismic Origin of Newly Recognized Landslides in Southeastern Sicily, and Its Significance inTerms of Hazard

Old, large, and dormant landslides were unexpectedly found in southeastern Sicily, a territory of known seismicity but commonly considered as landslide-free or almost so. Purposely undertaken investigations revealed that: (1) these landslides are scarcely compatible with the local geoclimatic environment; (2) they usually show low-angle basal shear surfaces, despite the fact that the properties of the forming material are generally good; (3) they fulfill the known relationships between earthquake magnitude and epicenter–landslide distance; (4) sources coeval with high-energy historical earthquakes occurred in 1169, 1542 and 1693 testify to the occurrence of earthquake-triggered landsliding; and (5) documentary material (presented here for the first time) correlates with certainty a specific landslide to the 1693 earthquake. This geological and historical evidence, accompanied by the absence of contrasting elements, leads us to conclude that these landslides are earthquake-triggered. Because of their typological and geometrical characteristics, nearly all landslides can be reactivated, which has serious implications in terms of hazard, particularly with respect to lines of communication. Obviously, every action aimed at preventing or mitigating risks must start from the awareness of the causative processes, a condition substantially unsatisfied at the moment in SE Sicily. The paper concludes by emphasizing the opportunity not to trust excessively beliefs that, although shared, have never been really checked.     

滑坡稳定性的模糊综合评定：以陕西渭南地区重点滑坡为例

本文选用地形地貌、岩性结构、构造、大气降雨、水文地质和人类活动6个定量化的环境因子作为评定滑坡稳定性的标志。利用模糊综合评判方法,对陕西渭南地区数十个滑坡的目前稳定性作了分级判别。按渭南地区的实际情况将其稳定性分为稳定滑坡、较稳定滑坡、不稳定滑坡三级,其结果与实际较为符合。     

小灾害引发大灾情：1997年陕西延川县永坪镇崩塌灾害的思考

１９９７年１１月２０日,陕西延川县永平镇发生崩塌灾害,崩体仅４２００ｍ３,但损失惨重．本文在简述灾情的基础上,分析了灾害的成因,并就黄土高原区减轻滑坡、崩塌灾害所造成的损失提出了相应的对策．     

滑坡加固方案优化选择的灰色系统方法

综合利用了灰色系统理论的局势决策及线性规划方法, 为滑坡的加固方案提出了一种优化选择方法, 并以实例说明了该方法的实用性和可靠性。     

Stability analysis and comprehensive treatment methods of landslides under complex mining environment—A case study of Dahu landslide from Linbao Henan in China

A case study of Dahu landslide from Linbao Henan in China was discussed in this paper. Based on various kinds of basic data, the 3D numerical model of a geological structure which possesses all kinds of information including the mechanical characteristics and the geometrical parameters of geological discontinuities were known from previous works. Thus, both the whole geological structure and all kinds of geological components involved in a slope can be visualized on computer, the complicated analysis and calculation can be then carried out easily and effectively. Firstly, the combination of 3D numerical model with the limit equilibrium analysis theory in slope stabilization can easily provide the present stability factor. Then according to monitoring data of the total station, the potential sliding trends are analyzed if landslides do not occur. Secondly, there are a number of uncertainties on the factors of multi-forms of disaster, such as, rainfall, earthquake, and mined-out area. The unascertained mathematics theory is applied to the stability comprehensive evaluation. It shows four landslide bodies get to be at unstable state if there are some inducements. Thirdly, sliding distance and movement scope were predicted if landslides occur. On the basis of the analysis above, the treatment of the landslide body called isolated method of culvert was proposed. It has solved the contradiction of landslide and mining radically, and provides important technical assurance for safety and sustainable development of mine.     

基于GIS的中秦岭地区滑坡灾害易发性研究

本文以中秦岭地区为滑坡易发性评价对象,针对研究区的情况,选取了坡度、起伏度、地貌类型、岩性、土壤侵蚀强度、活动断裂距、地震动参数、地下水类型、多年平均降雨量9个评价因子,建立了研究区滑坡易发性评价的数据库。运用单因子概率比率模型对各因子和滑坡的相关性进行了评价,揭示了该区滑坡灾害类型特点及空间分布规律,明确了中秦岭地区滑坡地质灾害的极高易发、高易发三大聚集地区的位置。     

The socioeconomic effects of a landslide in Western Washington

Abstract

Landslides can create permanently unstable sites that cannot be repaired or developed, and as a result, can cause severe economic and social consequences for families and communities. This study examines the economic and social effects of a landslide that struck Western Washington in February 1999. Two years after the landslide, property owners completed a confidential questionnaire. Property owners experienced significant personal financial losses and received little financial assistance to recover. Most (93%) did not receive any relief from their insurance policies, and 7% received only temporary rental assistance. Participants reported a variety of monetary and personal losses that were associated with emotional distress. They also reported a variety of gains and new perspectives on life. In this paper, we consider mechanisms to reduce the economic losses of landslides as well as implications and future research directions.     

顺层岩坡优势面水力学作用研究

分析了地下水对顺层岩坡优势面水力学作用的机理,指出了水头高度与稳定性系数之间的关系,提出了导致边坡失稳的极限水头值ｈ１．用于岩坡预测预报的预警水头值ｈａ以及水力学稳定性判据ｈｃ,并给出了计算方法。     

秦岭、巴山地区山地自然灾害综合研究──以陕西柞水踩玉河流域山地自然灾害为例

本文讨论了在秦岭、巴山地区开展山地自然灾害综合研究的有关问题．并通过陕西柞水踩玉河流域的现场考察，总结研究了该流域洪水、滑坡、泥石流等山地自然灾害的主要特征，致灾原因以及防御对策等。本文对试图用科学的方法减轻山地自然灾害作了有益的探讨。     

油库基础安全评价与工程治理

针对油库基础建于红石包滑坡体上 ,应用神经网络方法对滑带土强度参数进行估算 ,采用剩余推力法对油库基础进行安全评价。研究表明 ,在 175m库水位 ,饱和地下水、暴雨入渗、地震等因素的共同作用下 ,油库基础可能会产生变形 ,甚至失稳。因此 ,在工程治理设计中 ,采用悬臂桩、预应力锚拉桩进行支挡 ,有效地控制油库基础变形