西霞院水电站厂房软岩基础处理研究

Study on Soft Rock Foundation Treatment of Xixiayuan Powerhouse

西霞院电站厂房地基为第三系软岩,为防止电站坝段的渗透破坏,厂房地基设悬挂式防渗帷幕;为减小不均匀沉降,控制坝段之间的沉降差,在电站下部大体积混凝土部位设置纵向键槽;为克服基础上下游部位的应力集中现象,在基础上下游侧设置素混凝土桩。厂房基础面尽量设计成平面,同时在桩顶设置碎石垫层,防止基础出现集中应力,以改善地基应力分布,提高地基稳定性。

The foundation of Xixiayuan powerhouse belongs to Tertiary soft rock． In order to prevent destruction by percola．tion,it builds a suspended impervious curtain in the foundation． It controls the difference of sedimentation between thedam sections and builds longitudinal key bed at the mass concrete under the power station for reducing uneven settle．ment．It builds plain concrete piles both in the upper and downstream of the foundation for avoiding the situation 0f con-centrated. stress happened there．It should try to design the foundation surface as plane and in the meanwhile t0 buildcrushed bedding on top of piles for preventing concentrated stress happened in the foundation,improving the stress dis—tribution and increasing the stability of the foundation．