Strength of Cement Bonded Steel Connections in Glue Laminated Timber
Degree GrantorUniversity of Canterbury
Degree NameMaster of Engineering
The use of epoxy bonded steel connections is gaining increasing acceptance not only in New Zealand but worldwide, due to ongoing research and development. Of concern is the fire resistance, as it has been observed that heat affects the strength of epoxy and consequently the pull out strength of the connection. This report presents an investigation of the use of cement grout for bonded steel connections in glue laminated timber. It is intended to make cement grout a possible adhesive alternative to epoxy for bonded steel connections, with regard to better fire resistance. Small sized tests of wood and cement were carried out. In the study, ten various designs of the connection with variables of embedment length, hole geometry and reinforcement were tested in tension to find out their effect on the pull out strength of the connection. The results show that the bond between timber and cement is the main problem due to the fact that cement does not bond to timber. To prevent the steel-cement block from pulling out, tests were carried out using additional screws and bolts, which increased the strength significantly, compared to connections with straight holes. A minor increase of load capacity was achieved in connections with a distinct key between the cement and the wood. An equation was developed to predict the strength of connections using screws or bolts as reinforcement.
SubjectsField of Research::09 - Engineering::0905 - Civil Engineering::090502 - Construction Engineering
- Engineering: Reports