Test Study On Dynamic Parameters Of Cushion And Complex Subsoil

Through in-situ block-foundation forced vibration testing for cushion and complex subsoil, the test data are analyzed, the correlation between coefficients of subgrade different directions reaction are discussed, the correlation applying for natural subsoil is not suitable to cushion and complex subsoil, therefore, the available correlation for cushion and complex subsoil is brought forward.Utilizing test data of wave velocity measurement for cushion and complex subsoil, according to elastic half-space mode, coefficients of subgrade reaction are calculated. Coefficients of subgrade reaction obtained by calculation and test are contrastively analyzed, under the condition that foundation area is small, calculation value is on the high side. After influence factors of coefficients of subgrade reaction are taken into consideration in theroy, especially, variety of subsoil and range of wave velocity, the method of determining the coefficients of subgrade reaction through reduction coefficient α modifing calculation value is put forward.After damping ratios obtained by experimental, calculational, empiric method are contrastively analyzed, the data got by empiric method is proved that met the case in practice, moreover, this method is simple and convenient.The experimental data and method of determining dynamic parameter for cushion and complex subsoil supply reference to revising Code for design of dynamic machine foundation and designing in project.Additionally, dynamic parameters of single pile determined by empiric, experimental, academic three methods are analyzed, the influence factors are discussed, advantages and disadvantages of academic method are explained.