Improving Developmental Characteristics of Reinforcing Bars

9402563达尔文这项研究代表着美国40多年来对钢筋几何形状的第一次重大重估的继续。这项研究利用当前的研究努力，开发出新的变形模式，以优化钢筋的发育特征。试验被用来评估新钢筋的粘结性能的改善，无论有没有环氧涂层，作为约束钢筋、保护层和钢筋间距的函数。在循环荷载作用下，对新型钢筋的粘结性能进行了评价。断裂力学概念和荷载和抗力系数设计技术用于开发合理的设计程序，而不是经验的设计程序。这项研究是与钢筋生产商、制造商、涂层涂布商和环氧粉制造商共同进行的。重点是改进的钢筋变形模式，具有成本效益和实用性。

9402563 Darwin The research represents the continuation of the first major revaluation of reinforcing bar geometry in the United States in over forty years. The study capitalizes on current research efforts to develop new deformation patterns that optimize bar development characteristics. Tests are used to evaluate the improvement in bond provided by the new bars, both with and without epoxy coating, as a function of confining reinforcement, cover, and bar spacing. The bond characteristics of the new bars also evaluated under cyclic loading. Fracture mechanics concepts and load and resistance factor design techniques are used to develop rational, rather than empirical, design procedures. The research is carried out in conjunction with reinforcing bar producers, fabricators, coating applicators, and epoxy powder manufacturers. Emphasis is placed on improved bar deformation patterns that are cost effective and practical.