| The Large diameter squat silo is a new silo type introduced and built in recent years. There is no appropriate formula for calculating lateral wall pressure, and the overpressure problem caused by top pile is not well solved. Therefore, it is the urgent problem to be solved in the practical engineering. To solve these problems, systematical research is carried out in this dissertation.Based on theory of limit analysis, and started with active bulk-solid pressure of silo, the lateral pressure exerted by bulk materials is studied by the method of combination of theoretical analysis and finite element analysis, which provides foundation for the design and inspection of silo.The main contents of this dissertation are listed as follows:(1) The active bulk-solid pressure on deep silo's wall is analyzed by upper limit analysis. Critical ratios of height to diameter between shallow bins and deep bins (ξ_c) with differentparameters are obtained. Comparing the ratio of height to diameter of silo (ξ ) which is to be designed with the critical ratio of height to diameter (ξ_c.), designers can make certain the silois shallow bin or deep bin. And then, designers can use corresponding theory.(2) Mechanical models of silo of different cases are put forward. Therefore, a new method for calculating lateral wall pressure on silos is developed.(3) Lateral pressures with different ratios of height to diameter are calculated and analyzed.(4) The lateral pressure is predicted by the large-scale finite element analysis software (ADINA). Contact element and elasto-perfect plastic constitutive model are adopted, and effects of Young's Modulus E, Poisson's ratio v and internal friction angle q> are discussed.
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