Behavior of timber-timber composite structure connected by inclined screws

Building constructions, buildings and structures
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Abstract:

The behavior of timber composite structure made of cross laminated timber (CLT) panel and glued laminated timber (GLT) beam was considered in this paper. Bending tests of a CLT-GLT composite structures with and without fasteners were conducted. CLT panel and GLT beam were connected by screws installed at a 45° angle to the GLT axis grain. It was experimentally proved that the application of inclined screws increases the strength of the CLT-GLT composite structure by 1.3 and 1.6 times, stiffness – by 1.6 and 2.1 times, shear capacity – by 2.1 and 3.5 times for two orientation types of CLT panel (CI and CII), respectively. Two types of CLT panel orientations were considered: with the top layer oriented parallel to the GLT axis (CI) and oriented perpendicular to the GLT axis (CII). The CLT-GLT composite structure with the top layer oriented parallel to the axis of the GLT beam has 50 % more strength and 14 % more stiffness than a composite structure with the top layer oriented perpendicular to the GLT axis. Based on numerical and experimental results, a design procedure was suggested to determine the strength and strain characteristics of the CLT-GLT composite structure connected by inclined screws.