The elastic tests were conducted by applying an initial load of 10 kN, increasing
in increments of 1 kN, with data recorded at each interval on all instrumentation.
The 10 kN load was held for 5 min, unloaded incrementally and all load removed
for a further 5 min prior to the second elastic loading test which proceeded in the
same manner. The tests to failure were carried out using the same process following
the previous elastic tests and subsequently loaded to failure. The response was
monitored through instrumentation and additionally documented using digital
imagery.
The post-tensioned beams where initially tested as above, prior to the application
of the tension force. Once complete the steel tendon was tensioned using a
13 ton hollow plunger cylindrical ram, located at one end of the beam. The ram
was secured using open grip barrel and wedge clamps, with a load cell and bearing
plates located against the timber, typical arrangement shown in Figs. 3a and 3b. The
tensile force was applied in increments, with deflection, strain and force data gathered
at each interval. Once the tensile force was recorded at 20 kN, elastic loading
followed by loading to failure occurred as detailed previously