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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。
With the wide application of anchor and shotcrete support in underground engineering and the improvement of current underground support structure calculation methods, taking into account the good rock quality of the oil tank tank and the good mechanical performance of the vault cylindrical structure, The structure of cantilever, bolt and shotcrete support structure can replace the current reinforced concrete structure, which can effectively improve the safety, economy and construction simplicity of the project. Considering that the vaulted cylindrical structure is mainly subjected to shear stress and hoop tensile stress, the shear strength and tensile strength are reduced at the same time, and two safety factors, shear failure and pull failure, are proposed. In addition to calculating the shear failure safety factor by the strength reduction method of finite element method, a method of calculating the safety factor of pulling failure is proposed. The stability safety factor of grade Ⅱ surrounding rock is calculated to be much higher than the design requirement, and grade Ⅲ surrounding rock also meets the design requirements. On this basis, put forward a practical anchor spray support structure form and design parameters. The research shows that the structure of the dome with an anchor and shotcrete support is a very promising structure and is proposed to be further tested and popularized in engineering.