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某桥是9跨20米上承板梁桥。与水流斜交约20°,桥下不通航。线路坡度为4.1‰,平面大部为直线。桥墩为圆端形重力式桥墩,扩大基础。基底为风化极严重(已呈紧密的粘砂土状)的花岗闪长岩,抗冲刷能力很差。河床为砂夹卵石,实测桥孔内最低冲刷点已低于桥墩基底近一米之多,推算桥墩附近局部冲刷可达基底下2—3米。建桥40年来,虽曾采取了不少的防护冲刷措施,但仍发生过冲倒翼墙二次,冲倒桥台二次,有一个桥墩向上游倾斜下
A bridge is 9 span 20 meters on the girder bridge. Diagonal intersection with the water about 20 °, the bridge is not navigable. Line slope of 4.1 ‰, most of the plane for the straight line. Pier pier for the round-shaped bridge pier, to expand the foundation. The basement is a very weathered granodiorite that has been closely weathered with sand and is poor in erosion resistance. The riverbed is sand-gravel, the lowest erosion point in the measured bridge hole has been less than one meter as much as the base of the pier, and the local scouring near the pier can be estimated to reach 2-3 meters under the foundation. In the 40 years since the bridge was built, although a lot of measures have been taken to protect it from erosion, it has still occurred that the wing wall has been overthrown twice, the abutment has been overthrown twice, and one pier has been tilted upstream