Prefabricated Vertical Drain (PVD) is a solution to increase the bearing capacity of a com-pressible soil by accelerating settlement process and release of excess pore pressure of the compressible soil. The PVD work is usually controlled by geotechnical instrumentations such as settlement plate to measure the settlement, piezometer to measure the pore pressure, and inclinometer to measure the move-ment of the soil. These instrumentations are used to determine the success of PVD works. Correlation be-tween the preload to the geotechnical instrumentations is when the preload height is increased, the settle-ment and the pore water pressure that occur will also increase. Then, the PVD will facilitate the excess of pore water pressure to dissipate rapidly. From the case study, the designed depth of PVD is 20 m with 1 m spacing and the preload height is 4 m. The expected settlement should be 2.8 m at 90% of consolida-tion in 6 months period. Actual result of measured settlement was lower than expected settlement. The re-sults of geotechnical instrumentation shows that a slower phase of preload embankment process shows a smaller increase in pore pressure compared to a quicker phase. It was due to a quicker phase of embank-ment construction with less waiting time caused the accumulation of excess pore pressure.
Menu