ABSTRACT

Using suitable bolted connectors in lieu of conventional welded stud connectors may have great advantages in terms of the accelerated construction of composite bridges and the concrete slab replacement considering the life-cycle design of composite bridges. An innovative demountable steel-concrete connector, which mainly consists of a short bolt, a long bolt and a coupler, is proposed in this paper. Compared with other existing demountable bolted connectors, the proposed innovative demountable connector could render the dismantling of concrete slabs more convenient. Static push-out tests are carried out on three groups of demountable bolted connector specimens for investigating their failure mode and the fundamental mechanical behavior. The test results demonstrate that the failure mode of proposed demountable connectors is that the shank of short bolts is sheared off directly without local concrete crushing under couplers. The shear bearing capacity can be approximately estimated as 0.8 times of the tensile strength of short bolts. The peak slip of the steel-concrete interface grows with the increase of the bolt shank diameter. The clearance between bolt shank and bolt hole has an effect on the shear stiffness of innovative demountable connectors. The fundamental mechanical behavior of the innovative demountable connector can be a reference for the connector arrangement in the steel-concrete interface of composite bridges employing the proposed innovative bolted connector. Keywords: composite bridge; demountable connector; shear behavior; push-out test; accelerated construction