解放前,由于我国建材工业落后,再加上帝国主义要倾销它们的钢铁,铁路桥梁大多数采用进口钢梁。钢筋混凝土桥梁为数不多,且都是小跨度,就地灌筑施工。因此,在解放前并不存在混凝土桥梁的车辆运输问 Before the liberation, due to the backwardness of China’s building materials industry, coupled with the imperialism to dump their steel, most of the railway bridges imported steel beams. Reinforced concrete bridge is one of the few, and are small-span, on-site irrigation construction. Therefore, there is no question of vehicle transportation of concrete bridges before liberation