Using our CPT equipment and a bit of lateral thinking, we’ve developed a wee system for undertaking mini zone load tests. At our customer’s request, and with a view to fulfilling verification requirements of structural fill under NHBC Chapter 4.6 we undertook 2nr tests on site last week.
The system allows simulation of a reinforced strip foundation via a test beam loaded in stages up to a constant load of 120kPa while measuring displacement and, crucially, the development and dissipation of excess porewater pressures directly underneath the test beam under constant load. The ability to measure excess porewater pressure development allows us to assess if the test is drained or undrained (here drained) and, if the latter, assess primary consolidation as well as creep settlement to allow a reasonable extrapolation of the short-term test over a longer time horizon.
