( 2 ) the method of finite element discrete and optimal parameter back analysis is adopted . ( 3 ) concentrated on the question of high external water pressure of the deep - lying tunnel , the basic theory and method calculating external water pressure are systematically studied . ( 4 ) based on jinping cascade 2 hydropower station , numerical simulation rain infiltration of seepage field under different drainage pattern and grouting pattern are studied , also , the high external water pressure is analyzed and studied and some seepage control measures are put forward ( 2 )采用有限元离散?优化法进行参数的反演分析； ( 3 )针对深埋隧洞的高外水压力问题，进一步分析和研究了衬砌水荷载及外水压力的作用机理和计算方法； ( 4 )以锦屏二级水电站深埋长引水隧洞作为本文的主要研究对象，采用考虑降雨入渗渗流场分析的方法对排水方案和灌浆封堵方案不同情况下的渗流场的水头分布进行了数值模拟，并对其外水压力进行了分析和研究，提出了渗流控制的具体措施。
In order to calculate the high external water pressure , the rock seepage field and external water pressure coefficient should be treated in detail . concentrated on the questions of high external water pressure and flow of the deep - lying tunnel , the basic theory and method calculating external water pressure are systematically studied , the high external water pressure of jinping cascade 2 hydropower station is analyzed and studied in detail 本文在总结前人研究成果的基础上，围绕深埋隧洞的突涌水和高外水压力问题，系统地研究了深埋隧洞衬砌水荷载和外水压力的作用机理及计算方法等理论，并对锦屏二级水电站深埋引水隧洞的外水压力问题进行了详细的分析和研究。
