【作者】 禹芝文；

【导师】 姜弘道； 胡斌；

【作者基本信息】 河海大学 ， 土木工程， 2005， 硕士

【摘要】 向家坝水电站右岸地下厂房安装4台单机容量为75万kW的机组,主厂房开挖跨度达到31.40m/33.40m(岩锚梁上下),其开挖跨度为目前国内已建、在建和拟建电站中最大的,洞室围岩倾角平缓且含有开采历史的煤层,2级软弱结构面发育,水文地质条件复杂,因而地下洞室的围岩稳定和支护设计是向家坝水电站设计的关键技术问题之一,直接关系到工程安全和投资。因此有必要进行洞室围岩稳定分析计算,分析围岩应力变形特点,为支护设计提供数值依据,从而达到优化设计的目的。本文主要研究了地下洞室支护设计方法和围岩稳定分析方法等问题。 首先采取规程规范、Q系统和类似工程及工程经验等方法,论证向家坝地下厂房采用锚喷支护措施是可行的,并初拟主要洞室的支护参数,具体分析主要洞室工程地质特点,结合块体稳定分析成果,提出主厂房和主变洞顶拱及边墙采取系统预应力锚索等加强支护措施,采用平面和三维有限元等方法进行支护参数比较,从而提出主要洞室的支护型式和参数。 为对地下洞室围岩稳定有一个整体论证,分析厂区地质构造和实测地应力成果,进行了初始地应力场反演分析;根据洞室群布置特点,进行了开挖程序研究;然后采取三维弹塑性损伤有限元分析进行洞室围岩稳定分析,包括渗流场对围岩稳定的影响,综合评价地下洞室的稳定条件。 围岩稳定分析成果表明,向家坝地下厂房围岩整体稳定性较好。更多还原

【Abstract】 The right underground powerhouse of Xiangjiaba Hydropower Station is installed with four units of installed capacity 750MW each; the excavated span of the machine hall reaches 31.40m/33.40m (up and down the rock anchored crane beam), which is the largest one among the completed, under construction and planned projects. The surround rock of the underground chambers is of slight dip angle and contains coal layers that had been mined in the history, in which the grade II weak structures develops and hydrological geology condition is complex. The stable of surround rock and supporting design of underground chambers is one of key technologies concerned of the design of Xiangjiaba Hydropower Station; it may affect the safety and investment of the project. So it is necessary to conduct calculation and analyses on the surround rock of the underground chambers, to analyses the stress and deformation characteristics of surround rock is to provide proofs for the supporting design to realize design optimization. This thesis focuses on the studying methods of the supporting design and analyses on the surround rock.Firstly it is to demonstrated that adopting the supporting of anchoring and shotcrete is feasible by adopting methods of codes, specifications, Q system, similar projects and other projects experiences, then to put forward adopting strengthening supporting measures such as pre-stressed anchorage ropes for the arch top of machine hall and main transformer chamber and the side walls through determining the supporting parameters and analyzing the engineering geology characters of main chambers as well as considering the analyses results of rock block stable, at last the supporting types and parameters of main underground chambers are suggested after the parameter comparison has been completed by the methods of plan and three-dimension finite element.In order to conduct a general reasoning on the stable of underground surround chamber, the results of geological structure and site crust stress in the powerhouse area have been analyzed and counter analyses on the primary crust stress field has also been conducted; excavation process has been studied according to the arrangement character of underground chambers; then the stable analyses of surround rock has been done by adopting three-dimension elastic plastic damnification finite element with consideration of the affection of seepage field to surround rock stable, finally the stable condition of underground chambers has synthetically been appraised.The stable analyses results for the surround rock of underground chambers indicate that the whole stability of surround rock of underground powerhouse is relatively good.更多还原