关于《水运工程混凝土结构设计规范》的建议

Suggestions on"Design Code for Concrete Structures of Port and Waterway Engineering"

《水运工程混凝土结构设计规范》中混凝土构件裂缝宽度计算公式计算的裂缝宽度较大,一般裂缝宽度要求控制截面的配筋,限制了高强钢筋强度的发挥,不利于高强钢筋的推广,建议修订水运规范裂缝宽度计算公式,裂缝宽度计算公式可参考公路工程中公式。规范中未规定先张法预应力混凝土构件的预应力传递长度的确定方法,对采用冷拉预应力钢筋的先张预应力构件,建议规范给出预应力传递长度确定方法,现阶段可按建筑规范公式计算。工程中采用大直径吊环的情况比较普遍,吊环材质建议采用HPB300钢筋或Q235b圆钢。

In the"Design Code for Concrete Structures of Port and Waterway Engineering",the crack width calculated by the formula for calculating the crack width of concrete members is large.Generally,the cracks width requires the control of cross-section reinforcement,which limits the use of high-strength steel bars and is not conducive to the promotion of high-strength steel bars.It is suggested to revise the formula for calculating crack width in the code.The revised formula can refer to the formula in highway engineering.The method for determining the prestressed transmission length of the pretensioned prestressed concrete members is not specified in the code.For the pretensioned prestressed members using cold-drawn prestressed steel bars,it is recommended to specify the method for determining the prestressed transmission length.At this stage,it can be based on the building code.It is common to use large diameter lifting rings in the project.It is recommended to use HPB300 steel or Q235b round steel for the material of the lifting rings.