Bolt Connection Of Modern Bamboo-wood Structures Theoretical Analysis And Experimental Study

Connection is one of the critical components in modern bamboo-wood structure; bolted joint is one of the most important connection types. Therefore this thesis firstly provides background theory of dowel connection and bolt nodes in the current codes of timber structure, and then establishes shear capacity formulas with test data validation for modern bamboo structure. Finally, lateral resistances of bolted beam-column frames were conducted based on theoretical analysis, experimental research and finite element analysis.Theoretical analysis of single bolt connection is the basis of shear capacity formula for multiple bolt joints. Based on common failure modes of single bolt connection, this thesis analyzed shear capacity of single bolt connection with elastic, plastic and elasto-plastic methods and discussed the advantages and disadvantages of each method. With elastic analysis, bearing load of each bolt is proved to be unequal for multiple bolt connection, and then the calculation method of multiple bolt joints is illustrated.Difference between bolt connection of modern timber structure and that of modern bamboo structure is material diversity of joint component, or discrepancy between Glubam and wood, so codes for timber structure design can be references for the research on modern bamboo structure. This thesis particularly analyzed and compared origins of bolt joint shear capacity formulas in Chinese GB code, American NDS code and European Eurocode5 code and key parameters in each calculation specifications. Requirements for bolt joint are introduced and compared in current timber design code.Bearing capacity and detailing requirements are main component of bolt connection design in modern bamboo structure. Based on the widely used Johansen Yield Theory as foundation and referring to American NDS code and European Eurocode5 code, this thesis set up shear capacity formula of bolt connection for modern bamboo structure and valid its accuracy with the existing test results. As to the reasonable Glubam joint detailing requirements, the current timber specifications are recommended to refer due to the fact of scarce Glubam bolt connection tests.Four beam-column frame specimens with bolted joints selected from a demonstration project were subjected to lateral forces, to obtain monotonic and cyclic load deformation relationships, load angle relationships and bending shape of bolts. Lateral capacities were analyzed and load displacement curves were simulated for monotonic tests. For the cyclic tests, evaluating frames from aspects of energy dissipation, strength and stiffness degradation and frame ductility et al.Appropriate element types and material property were selected to establish Glubam beam-column frame models in ANSYS program. The corresponding constraints and loads to beam-column frame models according to the test conditions were applied, and then elastic interal force distribution of frame model was obtained. The finite element analyses agree reasonably well with the experimental results.