| The stress of vertical shaft, dewatering destruction process and collapsing process by the action of partial load are researched by the research technique of theory analysis and numerical simulation calculation in this article. The influencing factor and mechanics of sidewall destruction in the case of complex load is analysed. And the stress ofsidewall is analysed detailedly, the theory calculation formula of sidewall by the action of each load is deduced. The elastic-plasticity constitutive model and destruction crit erion for ferroconcrete sidewall in deep surface soil is presented. The deadweight stressfield model, dewatering destruction model and collapsing model by the action of partial load are established by the large general purpose finite element software ANSYS, a nd corresponding conclusion is obtained. The change of deadweight stress field and ground surface displacement fore and after the construction of shaft, as well as the stress and strain of every stratum layer are analysed for the deadweight stress field model.The dewatering destruction model of shaft is in the action of deadweight, level ground pressure and the time-increasing dewatering additive force. The eventual destructive p rocess as the increment of the dewatering additive force of sidewall is analysed. The time, position and progress of sidewall destruction are forecasted, at the same time, the stress and strain are analysed. The nonlinear flexion numeric analysis and elastic-plasticity numeric analysis are done for the numeric model of shaft by the action of partial load. The load size for the first destabilization and complete destruction of vertical shaft is obtained, and the stress and strain distribution and the plastic zone of the sidewalldestabilization is analysed. Comparing with the filed destruction and detection data, the numerical model in this article matches the practical situation, it can guide the destructive forecast of shaft and restoration in theory. |
PDF Full Text Request