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The influence of AC frequency , the content of sodium sulfate and curing time on the electrical resistivity of cemented soil was studied. Firstly, the impedance modulus of cemented soil blocks were measured and their electrical resistivity were calculated; then the primary and secondary factors influencing on the electrical resistivity of cemented soil were determined through orthogonal method; finally , the influence of three factors on cement soil resistivity was discussed qualitatively. It is found that the primary and secondary factors influencing on the electrical resistivity of cemented soil are the curing time, the content of sodium sulfate and the frequency. The electrical resistivity decreases with the increases of AC frequency and content, whereas increases with increasing curing age.

The mistuning of periodic structure was generally considered to be natural parameter mistuning, such as stiffness mistuning, damping mistuning and mass mistuning. However, in engineering practice, there was another kind of mistuning——force mistuning, which has not been studied yet. Based on a typical concentrated parameter model of periodic structure, the vibration characteristics, such as natural characteristic, vibration mode and vibration localization of periodic structure with different mistuning forms, were compared and analyzed. The results show that, as a new mistuning form, force mistuning won’t bring mode localization, while it could lead to vibration response localization

As an important and mature technology of researching material properties, ac impedance spectroscopy has successfully applied in many discipline except for soil research. Based on the experiments using TH2828A wide frequency LCR meter (from 50 to 106 Hz), the ac impedance characteristics with different water content of soil had been discussed. The results fully illustrate that the ac impedance is one of the basic property of soil,and the value of ac impedance parameter can be reflected the water content quantitatively. when using the fixed frequency to measure ac impedance of soil, it is most suitable as the frequency equals 104 Hz.The measure method of ac impedance have no effect to physical properties and internal structure of soil.

The paper proposed a new reinforcement technique-planting steel technique. By numerical simulation analysis of planting steel, the load – slip curve, the load – stress curve and others were obtained. Meanwhile, ultimate bearing capacity of angle was calculated, and the ultimate bearing capacities with the same model at different anchorage depths were compared. With the anchorage depth increased, the ultimate bearing capacity increased too. But while the anchorage depth increased to a certain value, the ultimate bearing capacity no longer increased. All these provided a theoretical basis for the engineering application of planting steel technique.