Dynamic Response Of Waste Tire And Triaxial Geogrids Composite Reinforced Slop Under Seismic Excitations

With the rapid development of auto industry in China, all kinds of cars is rising at an alarming rate, the number of waste tires has also increased dramatically. Waste tires disposal has become a worldwide environmental problem. Engineers and researchers across the globe have been focusing on trying to transform the waste into treasure and seeking the best way of waste tire recycling. A series of laboratory model tests carried out found it beneficial to use scrap tires as geotechnical engineering materials in many geotechnical structures due to their merits of excellent mechanical performance. Two major benefits of using such materials were, first, reducing the cost of soil improvement techniques and, second, keeping the environment clean and safe compared to typical ways of disposal. Shaking table tests and Geo Studio numerical simulation analysis are conducted to study the dynamic performance including distribution of acceleration amplification factor under various conditions such as different earthquake waves,different peak ground accelerations(PGA)and different reinforcement method.The slope model includes unreinforced slope,triaxial geogrids,waste tires and triaxial geogrids composite reinforcement,waste tires and tire shreds composite reinforcement. The following major conclusions are drawn from the results obtained from the shaking table studies carried out on unreinforced slope and composite reinforced slopes model tests.(1)The seismic response of the reinforced slope is significant. By comparative analysis of acceleration magnification factor between the unreinforced and composite reinforced model tests,it was found that the maximum decrease amplitude appeared in triaxial geogrids slope model test. Compared to the slopes of triaxial geogrids,waste tires and triaxial geogrids composite reinforcement, waste tires and tire shreds composite reinforcement,the former average acceleration magnification reduction is 1.4 and 2 times greater than that of the latter two.It was found that the maximum decrease of acceleration magnification for triaxial geogrid reinforcement is 37.5% and it is 30% for the triaxial geogrid and tire composite when compared to unreinforcement under Wenchuan wave.(2)By different reinforcement methods,acceleration amplification factor of the slope increases with the improvement of seismic excitation in a nonlinear way. But compared with the unreinforced slope,the acceleration amplification factor shows significant amplification decrease with the input of peak ground accelerations.(3)Response of the slopes for seismic excitation is not uniform along the slope but varies with the elevation. Along the surface of the slope about 1/3 of the height, acceleration magnification factor of various reinforced slope and unreinforced slope increase gradually with the increase of elevation,and the maximum accelerations is reached on the top of the slopes.(4)Based on the module of QUAKE/W in Geo Studio2007, numerical simulation analyses are conducted to study the dynamic performance of slope models under different peak ground accelerations(0.1g and 0.4g respectively) of Wenchuan wave. The slope model includes unreinforced slope,triaxial geogrids,waste tires and triaxial geogrids composite reinforcement.The result of the numerical simulation analyses shows that seismic response of triaxial geogrid reinforced slope is better than that of waste tires and triaxial geogrids composite reinforced slope, and unreinforced slope has high possibility of damage or collapse in the earthquake.