织毕铁路架盖河大桥桥位岸坡稳定性评价

The Bank Slope Stability Evaluation of Jiagai River Bridge in Zhijin-Bijie Railway

研究目的:近年来,随着大量山区铁路的修建,高山峡谷区的岸坡稳定性评价对线路方案的确定具有越来越重要的作用,本文意在通过分析织毕铁路架盖河大桥的区域工程地质条件、桥位的岸坡稳定性及岸坡稳定角,以确定合理、经济的桥梁跨度,为桥梁跨度设计提供依据。研究结论:通过对架盖河桥位工程地质条件综合分析,得出以下结论:(1)从第四道卸荷裂隙至河岸边区域为不稳定区,该区域不能放置桥墩;(2)架盖河北岸岸坡稳定,南岸有卸荷裂隙分布,岸坡稳定坡角为65°;(3)桥梁主跨度采用192 m跨度,对卸荷裂隙进行注浆封闭处理;(4)峡谷区线路选线应选择在地形开阔、山体稳定、岩体完整的地方通过,峡谷岸坡应进行稳定性评价分析,确定岸坡角,墩台基础应置于稳定岸坡线以下一定深度内;(5)本文可作为高山峡谷区桥位选址、岸坡稳定性评价的参考。

Research purposes： In recent years, the role of bank slope stability evaluation in alpine valley region is moreand more important to the determine of route scheme with the large number of the mountain railway construction. Thispaper is intended to determine the bridge span which is reasonable and economical by the analysis of regional engineeringgeological condition, bank slope stability and bank stability angle of Jiagai River Bridge in Zhijin - Bijie Railway, toprovide the basis for the design of the bridge span.Research conclusions： The conclusions can be drawn through the comprehensive analysis of engineering geologicalconditions of Jiagai River Bridge site. （ 1 ） The area from the fourth stress - release crack to fiver cliff is unstable region,which can not place bridge pier. （2） The north bank slope of Jiagai River is stable and the south has stress - releasecrack, the stability of the slope angle is 65 °（3） The bridge main span is determined as 192 m, and＇ the stress -release crack were sealed with grouting. （4） Canyon area line should select the region which has open terrain, slopestability and rock mass integrity. Bank slope stability evaluation should be carried out. The slope angle should beconfirmed and the pier foundation should be placed below the bank slope stability line within a certain depth. （5） Thispaper can be used as a research reference for bridge site selection and bank slope stability evaluation in alpine valleyregion.