Remarkable progress has been made in the safety technology of a car, and in recent years there has been strong demand for a safety sight-seeing bus. For this reason, safety bus structure is essential to reduction in casualties, and com puter simulation is indispensable for developing a safety bus. However, the structural analysis of a bus is so time consuming because of the enormous number of elements of a vehicle model.

This paper deals with structural analysis method for a bus in the event of rollover to reduce the calculation time to a reasonable one. A common crash analysis solver is modi fied in our method by reducing the number of integration cycle with respect to time in the explicit finite element method.

Rollover test and computer simulation have been per formed based on the ECB R66 regulation which specifies European rollover test standards. Deceleration and displacement of critical points on the bus have been measured during the time the vehicle is being deformed. As a result, quite a good agreement has been achieved between the test results and the simulation ones.