汶川地震灾区地质环境演化过程与后重建灾害防治措施

汶川地震发生在地质环境脆弱的山区,震后内外地质营力加速了灾区地质环境变迁,在变迁过程中,会出现不同的地质作用和地质灾害。本文通过研究灾区地貌变化、地表破坏、山体震裂、水文地质条件改变、地质灾害发育特征等地质环境现状,分析震后斜坡演化过程、地表地质环境变迁过程、外界因素的影响、崩滑流地质灾害转化关系,总结了地质环境变迁过程中地质灾害的发育分布特征并提出后重建阶段地质灾害防治措施:(1)震后地质环境的变迁加快,各种地表斜坡地质环境破坏演化对外界因素处于高度敏感时期。(2)地震及其余震的反复冲击破坏,外界荷载的瞬间叠加,未来数十年内,地质灾害处于高度频发、多发、突发时期。(3)后重建阶段,应加强地质灾害调查评价,注重特殊时期和重要地段的灾害防治,采取调查评价+群测群防+监测预警+避让搬迁+工程处治等多种措施组合防治震后地质灾害。

GEOLOGY ENVIRONMENT EVOLUTION PROCESS OF WENCHUAN EARTHQUAKE EPICENTER AND DISASTER PREVENTION AND CONTROL MEASURES FOR POSTRECONSTRUCTION

Wenchuan Earthquake happened in weak geological environment of the mountainous area. Both internal and external earthquake vulnerable geologic forces can accelerate the geological environment change in the disaster area. Changes in the process can appear different geological effects and geohazards. People have paid full attentions to the earthquake secondary geological hazards. In the disaster reconstruction process, they notice the geological hazard survey and evaluation, and site selection from fault zone. They can avoid major geological disaster and bad geological, major geological disasters to the management. However, after the earthquake, disaster geological hazards on the lag of the damage still beyond the people's imagination. The Zhouqu debris flow, Qingpping debris flow, the 213 national highway destroyed by the earthquake are warned us that geological disaster prevention and control of the situation are still severe. The need is increased for attention to disaster geological environment, the present situation and the prevention of geological disasters science and technology research. Early effective means of disaster are also needed. This paper studies the disaster area landscape change, the surface damage, mountain earthquake cracked, hydrogeology conditions change, geological disasters such as development features of geological environment situation. It analyzes the evolution process of the earthquake, the surface slope geological environment change process, the influence of the external factors, collapse, landslide and debris flow relationship geological disasters. It summarizes the geological environment changing process of the development of the geological disaster distribution characteristics. It proposes the rebuilding after the geological disaster prevention and control measures to stage. Conclusions are as follows.(1)After the changes of the geological environment speeding up, all kinds of surface slope destruction of geological environment evolution of external factors in a highly sensitive period.(2)the earthquake and its aftershocks of repeated impact damage, outside the moment of load overlay, decades, geological disaster on high frequency, multiple, an unexpected period.(3)After the reconstruction phase should strengthen the investigation of geological hazard assessment, and to pay attention to the special period and the important section of disaster prevention and control, to take the investigation and assessment of predicting+the crowd monitoring to prevent+monitoring and warning+move geological hazards+engineering management and so on.the many kinds of combination prevention and control measures have to be adopted after geological disasters.