不久前在规定开挖体积时是不进行计算的。多数桥位的运营实践证明,不计算而确定开挖体积不只一次地带来了严重后果。例如,开挖体积规定过大并把它纳入一般冲刷计算时,在桥位投入运营数年后,开挖的地方不是局部淤积就是全部淤积。并且在各种大洪水的通过时,桥下会发生大大超过计算的深冲刷,因而桥梁基础埋置深度显得不 Not long ago, the excavation volume was not calculated. Operational practice at most of the bridge sites has proved that determining the excavation volume without calculation has serious consequences, more than once. For example, when the excavated volume is too large and included in the general scouring calculation, a few years after the site is put into operation, the excavation is either partial or total deposition. And in the floods of various passes, the deep scour will occur much more than calculated under the bridge, so the depth of the bridge foundation embedding does not appear