Study On The Mechanical Property Of Steel Reinforced Concrete Composite Floor Of Inclined Shaft Lining In Deep Water-rich Bed Rock

Inclined shaft of freezing sinking has become an important development way of mine construction in west China. The floor of inclined shaft lining is always the most disadvantaged part, the floor of shaft lining under high water pressure after thawing prones to phenomena such as uplift and broken, affecting the normal functioning of shaft lining. To resolve this problem, simply increasing the floor thickness of shaft lining and increasing the reinforcement ratio is difficult to solve the problem effectively. To solve this problem, this paper proposes a structure of inclined shaft lining floor with shape steel and studys its mechanical properties.First, based on the typical parameters model, this paper studys the mechanical properties of inclined shaft lining with stubbles of two different construction technology. According to the calculated data, the level stubble is more favorable than the vertical stubble for the conclusion.A reasonable shaft pouring process and a structure of inclined shaft lining floor with shape steel and the form of shape steel are proposed.Then, elastic characteristics of inclined shaft are calculated in uniform water pressure at different bonding state between shape steel and concrete(completely adhesion, completely separate, typical cohesion) in different geometrical and physical parameters under three-dimensional finite element model. The results show that: when the pressure is 2MPa, shaft lining with shape steel is applied to reduce the displacement of the center of the floor by about 9.5%, inside tensile stress is reduced by 8.8%,and the lateral stress is reduced by 12.4%, the effect of shape steel is obvious; The influence of the radius of the floor,the height of the thickness of the shape steel, shape steel longitudinal spacing and other factors on the mechanical properties of the elastic lining structure is larger; Elastic characteristic of inclined shaft of completely adhesion with various factors is similar to the elastic characteristic of inclined shaft of completely separate, the maximum difference of hoop stress and radical displacement between the two ultimate state results are not more than 3%.The hoop stress and radial displacement of inclined shaft with shape steel and concrete typical adhesion is always between the status of completely adhesion and completely separate. The method of increasing the adhesion between the shape steel and concrete should be taken during the construction of inclined shaft.Then, ultimate bearing capacity of inclined shaft is calculated in uniform water pressure at different bonding state between shape steel and concrete(complete adhesion, completely separate, typical cohesion) in different geometrical and physical parameters under three-dimensional finite element model. The results show that: Ultimate bearing capacity of inclined shaft of completely adhesion is 28.9% larger than inclined shaft without shape steel; Ultimate bearing capacity rule of inclined shaft of completely adhesion with various factors is similar to the ultimate bearing capacity rule of inclined shaft of completely separate, the maximum difference of the ultimate bearing capacity between the two ultimate state results is not more than 3%; The ultimate bearing capacity of inclined shaft with shape steel and concrete typical adhesion is always between the status of inclined shaft of completely adhesion and completely separate. The method of increasing the adhesion betwenn the shape steel and concrete should be taken during the construction of inclined shaft.Finally, this paper studys the elastic mechanical properties and the ultimate bearing capacity of inclined shaft with shape steel by the similar model test research. Deformation and stress of inclined shaft in test is similar to the result of numerical calculation, but the ultimate bearing capacity of the inclined shaft is larger than the numerical calculation,the reason may be the increase of thickness of shaft lining and binding effect of steel head,in addition, non-planar strain state of the shaft lining will increase the ultimate bearing capacity.