Experimental investigations of the dilatancy and particle breakage of gravelly material from the Zipingpu concrete-faced rock- fill dam, which was subjected to high-intensity seismic load during the 2008 Wenchuan eart...Experimental investigations of the dilatancy and particle breakage of gravelly material from the Zipingpu concrete-faced rock- fill dam, which was subjected to high-intensity seismic load during the 2008 Wenchuan earthquake, were conducted through a series of large-scale drained triaxial compression tests. A hyperbolic relation between the input plastic work and the degree of particle breakage was found for Zipingpu gravel, independent of the initial void ratio and confining pressures. The stress-dilatancy for Zipingpu gravel was analyzed and compared with data from two rounded alluvial and three angular quar- ried gravelly and rockfill materials in the literature. A nearly linear relationship between the dilatancy Dp and the stress ratio η was found at medium-to-large stress ratios before the peak stress ratio. The slope of the stress-dilatancy line before peak had slight dependence on the void ratio and confining pressure of the gravel. After peak, the stress-dilatancy relation shifts down compared with that before peak for the gravel specimen. The phase-transformation stress ratio decreased with increased con- fining pressure, with the exception of sub-rounded gravel with little particle breakage. A nearly linear relationship was found between the phase-transformation stress ratio Mf and the state parameter ψ for the Zipingpu gravel, regardless of the void ratio and confining pressure of the specimens.展开更多
基金supported by the State Key Program of the National Natural Science Foundation of China(Grant No.51138001)the National Natural Science Foundation of China(Grant Nos.51279025+1 种基金91215301&51508071)the Program for New Century Excellent Talents in University(Grant No.NCET-12-0083)
文摘Experimental investigations of the dilatancy and particle breakage of gravelly material from the Zipingpu concrete-faced rock- fill dam, which was subjected to high-intensity seismic load during the 2008 Wenchuan earthquake, were conducted through a series of large-scale drained triaxial compression tests. A hyperbolic relation between the input plastic work and the degree of particle breakage was found for Zipingpu gravel, independent of the initial void ratio and confining pressures. The stress-dilatancy for Zipingpu gravel was analyzed and compared with data from two rounded alluvial and three angular quar- ried gravelly and rockfill materials in the literature. A nearly linear relationship between the dilatancy Dp and the stress ratio η was found at medium-to-large stress ratios before the peak stress ratio. The slope of the stress-dilatancy line before peak had slight dependence on the void ratio and confining pressure of the gravel. After peak, the stress-dilatancy relation shifts down compared with that before peak for the gravel specimen. The phase-transformation stress ratio decreased with increased con- fining pressure, with the exception of sub-rounded gravel with little particle breakage. A nearly linear relationship was found between the phase-transformation stress ratio Mf and the state parameter ψ for the Zipingpu gravel, regardless of the void ratio and confining pressure of the specimens.
