前言随着我国四化建设的蓬勃发展,交通运输对公路桥梁载重的要求不断增加,越来越多的公路桥梁承载能力不能适应发展的需要。甚至在一些工业发达的国家也不例外。据文献报导,目前美国有40％的桥梁,日本有5500座桥梁均感承载能力不足。因此这一带有普遍性的问题已引起国际上的重视, Preface With the vigorous development of our country’s four modernizations, the requirements of transportation and transportation on highway bridges and bridges have been constantly increasing. More and more of the carrying capacity of highway bridges can not meet the needs of development. Even in some industrialized countries is no exception. According to the literature, at present, 40% of the bridges in the United States and 5,500 bridges in Japan feel inadequate in carrying capacity. Therefore, the issue of universality has drawn international attention.