| Budget Amount *help |
¥11,830,000 (Direct Cost: ¥9,100,000、Indirect Cost: ¥2,730,000)
Fiscal Year 2010: ¥1,560,000 (Direct Cost: ¥1,200,000、Indirect Cost: ¥360,000)
Fiscal Year 2009: ¥6,890,000 (Direct Cost: ¥5,300,000、Indirect Cost: ¥1,590,000)
Fiscal Year 2008: ¥3,380,000 (Direct Cost: ¥2,600,000、Indirect Cost: ¥780,000)
|
|---|
| Research Abstract |
Seismically induced slope failures have normally been evaluated based on force equilibrium on a potentially sliding soil mass. This force approach can evaluate a safety factor against slope failure, but cannot predict large sliding deformation, once failure occurs. In order to evaluate slope failures including flow failures from their initiation to termination, an energy approach has been developed, which showed that not only the travel distance of failed slope debris but also the threshold of failure initiation can be uniquely evaluated by seismic shaking energy. It seems quite unexpected that the energy, instead of conventionally used acceleration, can serve as a unique threshold for slope failures. In order to clarify the mechanism associated with the energy threshold, two types of model experiments have been performed ; (a) shake table tests on a rigid block resting on a sand slope with variable thickness and (b) loading tests of the same rigid block on the slope by horizontal pull force simulating the inertia force during shaking. The two test results, together with numerical analyses, have revealed that the energy per one cycle at the initiation of block sliding is almost identical with the work done in the load～displacement curve up to the peak load. Thus it has been clarified that the energy-base evaluation of slope failure initiation can be possible instead of acceleration in actual slope failure evaluations.
|
