GanjianInvestigating the shear properties of cemented clayey sand with a nano TiO2 additive

In this research a series of experimental tests were performed to investigate the effects of nano TiO2 (NT) on the triaxial behavior of cemented clayey sand (with variable amounts of kaolinite). To reduce the number of experiments, time and cost of research, the design and assessment of the experiments were performed using the response surface method (RSM). The amount of used NT was 0-4 wt% of cement, and the amounts of cement and kaolinite were 3-9 wt% and 10-30 wt% of soil respectively. The consolidated drained (CD) triaxial tests were performed for the confining pressures of 100, 300 and 600 kPa. The results of these tests showed that the amount of kaolinite clay at 20 % has the largest effect on the peak deviator stress and friction angle, but the soil cohesion has an ascending trend at 10-30 % kaolinite clay. The amount of cement in the range of 3-9 % causes an increase in the peak-deviator stress, shear strength parameters and the brittleness index. Also, the use of NT in a desirable amount (2 %) causes an increase in the peak deviator stress and the shear strength parameters.