Abstract:This paper aims to study dynamic responses and compare aseismic bearing capacity of herringbone micro-pile and parallel micro-pile retaining structures under EI earthquake action through large-scale shaking table tests. The objective of this research is to propose the structure which shows good aseismic bearing capacity and strong deformation resisting capability under earthquake condition. The results may be as a good reference for seismic design of slope engineering and micro-pile retaining structure. It is indicated that,under EI earthquake condition:The hillside soil pressure of two kinds of micro-pile retaining structures shows“K”shape distribution above sliding surface,and the earth pressure is the largest around sliding surface. The riverside soil pressure distribution characteristics of two kinds of micro-pile structures show different performance. In addition,the earth pressure of micro-pile under the action of bidirectional coupled earthquake is higher than that of unidirectional earthquake. At the sliding surface,the landslide thrust force of herringbone micro-pile bearing is twice to five times as strong as that of parallel micro-pile. The top beam displacement of parallel micro-pile is 2.2 cm more than that of herringbone micro-pile. Compared with parallel micro-pile,the aseismic bearing capacity and deformation resisting capability of herringbone micro-pile is stronger. Besides,there is hysteresis effect in the micro-pile peak value of seismic dynamic earth pressure,and the earth pressure near the sliding surface is undulating over whole time period of earthquake. The hysteresis effect of the earth pressure at the sliding surface is more significant than others. Lastly,the acceleration of the slope is magnified along the pile body,meanwhile the acceleration magnified effect is prominent when the earthquake action is greater,and the acceleration magnified effect reaches the peak near the slope surface.
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