The more severe deterioration parts of bridges are the side beams of bridges . the main cause of this is that the drainages of bridges is not good . that causes freeze - thaw damages and other bridge diseases 病害比较严重的部位多发生在桥两侧面的边梁，造成此现象的主要原因是桥面排水不畅，产生冻融破坏，并引起其他的病害。
