Effects of rock-support and inclined-layer conditions on load carrying behavior of piled rafts

Abstract

In this study, the load carrying behavior of piled rafts installed in inclined bearing rock layer was investigated for rock-mounted and -socketed conditions. It was found that settlements induced for an inclined bearing rock layer are larger than for a horizontal layer condition. The load capacity of piled rafts for the rock-mounted condition decreased as rock-layer inclination angle (theta) increased, while vice versa for the rock-socketed condition. The load capacities of raft and piles both decreased with increasing theta for the rock-mounted condition. When bearing rock layer was inclined, loads carried by uphill-side piles were greater than those by downhill-side piles. The values of differential settlements of rock-mounted and -socketed conditions were not significantly different whereas slightly higher for the rock-socketed condition. The values of load sharing ratio (alpha_p) and its variation with settlement were not markedly changed by the inclination of bedrock. It was shown that alpha_p for piled rafts installed in rock layer was not affected by theta whereas actual loads carried by raft and piles may vary depending on the pile installation and rock-layer inclination conditions.