复杂地震背景下新疆高土石坝抗震设计与应用实践

Seismic design of high earth-rockfill dam and its application practice under complicated earthquake background in Xinjiang

汶川地震后,国家颁布了新的地震动参数区划图和水电工程抗震设计相关规范。因此,针对新疆山区水库坝址区抗震设计烈度高、地质条件复杂的问题,为了更好的进行新的地震动参数区划、水电相关规范规定下高震区高土石坝的抗震设计和适应新颁地震区划条件下水电规范对老坝抗震复核的要求,结合近年来新疆高土石坝工程实践及国内外土石坝筑坝先进技术和经验,从高地震区动参数选取、坝体结构型式与坝料分区、防渗体结构、坝体压实与沉降变形控制、大坝抗震措施等方面对新疆高土石坝抗震设计和应用实践现状进行了系统总结,提出复杂地震背景下新疆高土石坝建设应遵循"稳、控、防、排"4字抗震设计理念进行抗震措施设计,并对新的地震动参数区划条件、新规程和规范要求下新疆高土石坝抗震安全评价及老坝抗震复核等工作中存在的问题进行了探讨,给出了相应的建议。对新疆土石坝抗震设计和应用实践的总结以及对新的条件和要求下新疆高土石坝抗震安全面临的问题的探讨和建议可为类似环境条件下的坝工建设提供技术借鉴。

After the Wenchuan Earthquake,new seismic zoning map and the relevant criteria of seismic design for hydropower project are promulgated in China.Therefore,targeting at the problems of the seismic design for high earthquake intensities and complicated geological conditions in the reservoir dam sites within the mountainous areas in Xinjiang,the status of the seismic design of high earth-rockfill dam and its application practice in Xinjiang is systematically summarized herein in combination with the engineering practice of the construction of earth-rockfill dam in Xinjiang and the advanced technologies and experiences of the construction of earth-rockfill dam at home and abroad in the aspects of the selection of the seismic ground motion parameter for high-intensity earthquake region,dam structure pattern and zoning of dam construction materials,anti-seepage structure,compaction and settlement deformation control of dam body,etc.,so as to make the seismic design of the earth-rockfill dam within high-intensity earthquake region well under the specifications from the new seismic ground motion parameter zoning and the relevant criteria of seismic design for hydropower project and adapt to the requirements from the criteria for the construction of hydropower project under the conditions of the newly promulgated seismic zoning map on the seismic checking of old dam,and then it is proposed to carry out the design of the seismic measure with the seismic design concept of"stabilization,control,prevention and drainage"for the construction of high earth-rockfill dam under the complicated earthquake background in Xinjiang,while the problems in both the seismic safety assessment of high earth-rockfill dam and the seismic checking of old dam in Xinjiang under the new seismic ground motion parameter zoning conditions and the requirements from the new criteria and specifications are discussed and the relevant suggestions are given out as well.The summary of the seismic design of earth-rockfill dam and its application practice in Xinjiang as well as the discussions and suggestions on the problems faced by the seismic safety of high earth-rockfill dam in Xinjiang under new conditions and requirements can provide technical references for the dam construction under the similar environmental condition.