基于极限分析上限定理的压气储能洞室抗隆起破坏准则

Anti-uplift failure criterion of caverns for compressed air energy storage based on the upper bound theorem of limit analysis

为研究压气储能地下岩石洞室在高气体内压作用下的隆起破坏模式,基于极限分析上限定理,在假设岩体服从相关联的Hoek-Brown准则条件下推导洞室隆起破坏函数f(x)和极限内压pu的表达式,考虑到压气储能洞室热力学响应规律,建立其抗隆起破坏设计准则,并且针对影响洞室隆起破坏函数f(x)和极限内压pu的参数进行敏感性分析,结果表明:压气储能洞室在高气体内压影响下的隆起破坏函数f(x)是一个典型的幂函数,其主要与岩石单轴抗压强度ciσ,Hoek-Brown经验参数A和B以及洞室埋深H有关,随着ciσ和A增大,f(x)的倾斜斜率逐渐减小,而随着参数B增大,f(x)的倾斜斜率逐渐变大;洞室的极限内压u p与破坏函数f(x)密切相关,当ciσ,A,H越大,极限内压u p的值也越大,而参数B越大,极限内压u p的值则越小。对比已有的压气储能洞室抗抬设计准则,提出的新设计准则全面考虑了岩体强度参数和破坏模式的影响,采用该准则将在安全的前提下大大降低洞室抗隆起破坏所需要的埋置深度,可以极大地减少压缩空气储能地下洞室的建设成本,有利于压缩空气储能技术的推广应用。

To investigate the uplift patterns of underground lined rock caverns for compressed air energy storage(CAES)under the action of high gas internal pressure,based on upper bound theorem of limit analysis,uplift failure function f(x)and limit internal pressure pu are derived under the assumption that the rock mass obeys the associated Hoek-Brown criterion.Considering the thermodynamic response laws of CAES caverns,an anti-uplift failure criterion is established.A sensitive analysis on the parameters affecting the failure function f(x)is performed.Research results indicate that the uplift failure function f(x)of CAES caverns is a typical power function,which is mainly related to the rock uniaxial compressive strength ciσ,Hoek-Brown empirical parameters A and B,and the buried depth H.The slope of f(x)gradually decreases as ciσand A increase,while gradually increases as parameter B increases.The limit internal pressure pu is closely related to the failure mechanism function f(x).The limit internal pressure pu increases as the parameters ciσ,A and H increase.However,as parameter B increases,the limit internal pressure pu decreases gradually.Compared with existing anti-uplift criterion of CAES caverns,the calculation method proposed in this paper fully considers the influence of rock mass strength parameters and failure patterns.Therefore,the use of this new criterion will greatly reduce the buried depth of the cavern to resist uplift failure under the premise of safety.As a result,the construction cost for CAES caverns will decrease greatly,which is conducive to promotion and application of CAES technology.