A simple formula for calculating pure shear strength of concrete is derived on the basis of the verified mathematical model of concrete failure surface, the ellipticparaboloid.
Identifying the basic properties of mining fissure ellipticparaboloid zone and gas delivery law governing goaf represents an effective measure to control gas.
研究采动裂隙椭抛带的基本性质及其采空区瓦斯运移的规律，可以采取有效措施进行瓦斯治理。
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An ellipticparaboloid is proposed as the failure surface for concrete under multiaxial Stresses.