Proceedings - 13th International Workshop on Micropiles - 2017, Vancouver, BC, Canada, (ISM, DFI, ADSC)
MICROPILES FOR COMBINED DEEP SLIP AND STRUCTURAL LOADING
Allan Herse CPEng, MIEAust, RPEQ, Lambert Ezaejugh PhD, CPEng, MIEAust, RPEQ and Kenneth Wilson BE Civil, MIEAust
The use of grouted injected micropiles in an A‐Frame configuration as a solution to slope stability problems has been well documented in case studies around the globe. Typically, they consist of a series of downslope and upslope micropiles installed through the failure plane with the pile heads terminating in a concrete capping beam. Despite its wide usage across the world, its use in Queensland, Australia is limited. The Queensland Department of Transport and Main Roads (TMR), with over 33,353 kilometres of road network under its jurisdiction, has traditionally continued to use established methods such as soil nails and soldier piles in managing slip repairs on their network. However, following severe weather events in 2011 to 2013which resulted in multiple slip failures, micropiles were first introduced as temporal stabilising measure. Since their introduction in 2011, TMR has subsequently allowed the use of micropiles as a permanent stabilising measure on a trial basis for the Gatton Clifton Road and Kin Kin Road slip repairs. The approval for their use followed a rigorous design / design review processes. It was intended that the performance of the remediated sites, which were instrumented and are currently being monitored by TMR, will form the basis for the acceptance or otherwise of the method as permanent stabilising measure on TMR road network. This paper examines the use of hollow bar micropiles which have been used in an A‐Frame arrangement to permanently remediate two deep slip failures at Gatton Clifton Road and Kin Kin Road in Queensland, Australia. At the Kin Kin Road slip, the micopile structure in addition to providing the stabilising action for a deep slip failure, also catered for the applied forces from a 1.5m retaining wall which facilitated a widening of the road.
|article #2646; publication #1033 (ISM- 2017)|