Experimental study on service life of foamed mixture lightweight soil based on method of accelerated stress tests

Based on the method of accelerated stress tests, the characteristics and distribution of fatigue life of foamed mixture lightweight soil (FMLS) which consists of cement, water and bubble are analyzed with the help of probability and statistics theory. The linear fatigue equation for FMLS is established based on a series of unbiased estimations. At the same time, the service life of FMLS under normal traffic load is predicted. The research results indicate that the fatigue life of FMLS under identical traffic load is considered to have small discreteness according to the three indices of average value, standard deviation and variable coefficient, but the discrete degree increases with the increase of the accelerated stress. The results of linear regression indicate that the fatigue life of FMLS obeys the lognormal distribution. The fatigue life equation for FMLS is established, and the logarithm of fatigue life of FMLS proves to decrease with the increase of the accelerated stress according to the fatigue equation. Finally, the average service life of FMLS under normal traffic load is predicted to be about 73 years.