Monitoring modern timber structures and connections

Long term laboratory experiments have been set up to measure the time dependant performance of multi-nailed connections. Deformations are noted using manual dial gauges and a datalogger for recording strain-gauge based deformation gauges previously used in short term applications. The strain-gauges are bonded to stainless spring steel to give a direct strain to deformation relationship, these are cost effective measuring systems but compensation will need to be made for the long term drift and creep of the strain-gauges.
A 3 storey building in New Zealand has frames and energy dissipating rocking shear walls constructed from laminated veneer lumber (LVL) in 2010. Wall post tensioning, wall shortening, deformation of the energy dissipating devices, floor dynamics, moment rotations and mid span deformations are to be remotely monitored. Preliminary dynamic performance has been tested and verified the operation of the installed GNS accelerometers and allowed the initial dynamic modes to be identified.