SHEAR-STRENGTH OF OPEN-WEB PLATE GIRDERS WITH INCLINED TENSION BARS

Examination of previous research on the collapse behavior of conventional plate girders with slender webs in shear indicates that the major contributions to the ultimate load capacity of component panels are provided by the characteristic postbuckling diagonal tension field and the flange plastic moment capacity. An open-web plate girder, in which the contribution of the web critical strength in shear is replaced by engineered inclined tendons providing a reinforced tension field, is proposed and discussed. It is found that for every particular girder configuration, there is an optimal inclination of the tendons in order to maximize the overall ultimate shear load capacity. Parametric studies using computer-based mathematical models are conducted and verified with subsequent experimentation in the laboratory with small-scale physical models. It is concluded that open-web plate girders with inclined tension bars have the potential to offer an attractive design alternative to slender conventional plate girders when the overall strength is controlled by the shear capacity of the girder and lighter structural elements are desired.