The dynamic triaxial apparatus is the more important and popular testing apparatus in researching the soil’s dynamic properties. But the testing results are separate in some measure
which were caused by man made and the apparatus itself. For example
the phasic value of the bidirectional loads isn’t the value given in advance
which will lead to some error. So are the resistance and the hysteresis quality of the testing data from the apparatus. In order to enhance the exactness of the testing result
it is very essential to analyze the cause of error and to present some proposals about its mending.