地下油库锚喷支护拱顶圆筒罐室的设计与计算

随着地下工程锚喷支护的广泛应用,以及当前地下支护结构计算方法的提升,考虑到油罐罐室岩质条件好、拱顶圆筒结构受力好,为此提出采用拱顶圆筒锚喷支护结构形式取代当前钢筋混凝土结构,可有效提高工程的安全性、经济性和施工简便性。考虑到拱顶圆筒结构主要承受剪切应力与环向拉应力,为此对抗剪强度与抗拉强度同时进行了折减,并提出了剪切破坏和拉破坏两种安全系数。应用有限元强度折减法除计算剪切破坏安全系数外,还提出了计算拉破坏安全系数的方法。计算得到Ⅱ级围岩稳定安全系数远高于设计要求,Ⅲ级围岩也满足设计要求。在这一基础上提出了实用的锚喷支护结构形式与设计参数。研究表明,锚喷支护拱顶圆筒罐室结构是一种很有前景的结构形式,建议在工程上进一步试验与推广。

Design and Calculation of Anchor and Shotcrete Support for Dome Cylinder Tank Room of Underground Oil Storage

With the wide application of anchor-shotcrete support for underground engineering,the continual improvement of the calculation method for underground support structure,considering the good surrounding rock condition of underground oil storage,and the good mechanical characteristic of cylindrical structure,the anchor and shotcrete support of dome cylinder structure is proposed to replace the current reinforced concrete structure.The structure is safe,economic and simplicity in construction.On the basis of the dome structure mainly subjected to shear stress and loop tensile stress,two kinds of safety reserve factors were put forward to realize the reduction of the shear stress and loop tensile stress at the same time.The strength reduction method of Finite Element Method was used to calculate the shear safety reserve factor and tensile safety reserve factor at failure point.The safety serve factor of grade Ⅱ rock is much larger than designing requirement,and the grade Ⅲ rock also meets the designing requirement.On the above basis,this structure type and its designing parameters are advauced.The research shows that anchor and shotcrete support for dome cylinder tank room is most promising structure,and suggest making further test and spread.