粒子法による流木群の堰止め過程のLagrange解析

抄録

Recently, a potential of the production of drift timbers increases due to the existence of the fallen trees in mountainside caused by a gale of typhoon. Hence, the effect of drift timbers on river structures, such as a bridge, are required to be clarified. Here, the dam-up process of drift timbers at a small bridge in mountain stream are simulated by the MPS method, to which the subroutine for tracking the motion of rigid body is attached as a model of drift timbers. The mass conservation of fluid-timber mixture, the fluid-timber interaction, the inter-timber collision, and the fragmentation and coalescence of fluid including a water surface wave and a splash are well described by the present model. The complicated time-dependent process of the dam-up and resultant overflow at a small bridge are well reproduced.