With a crash barrier outside the surface treatment of materials used to waterproof the material.

室外用防撞护栏的表面处理所用原料为防水性的材料。

Ideally, the cars slide along this wall or crash barrier and dissipate energy and speed.

理想上, 赛车沿着这面墙或者是防撞护栏消散冲击力和速度.