Study on time-varying characteristics of similar material model strength and the regulation measures

Similar material simulation is an important research means in mining engineering. Similar material model errors will lead to instability of similarity degree between the model and the reality, reduce the reliability of simulation results and greatly limit the development of this method. By analyzing the error sources, this paper indicates that the time-varying characteristics of similar material model strength are the main restriction of using quantity method to evaluate similar material model. The test is carried out for the blocks of similar materials to study the relationship between moisture content and compressive and tensile strength. Then, the theoretical model about similar materials' moisture content and strength is established to process and analyze the test results. Test results show that the time-varying characteristics of similar material strength have significant impacts on simulation results. The similar material strength variation with moisture change can be divided into three phases, and the relationship between strength and moisture content is different for different lithological material blocks. On the basis, the regulation measures are proposed to reduce the model errors caused by time-varying characteristics of material strength. The influence mechanism of the effect of constant temperature and humidity on the test results through decreasing time-varying characteristics of material strength is analyzed in detail. Research results can provide basis for similar material model design and the reliability of monitor time series and simulation results. It is important to promote the use of quantity method to evaluate similar material model both in theory and in practice.