Abstract
Two Innovative Solutions Cases implemented by Geoharbour Construction Group in Indonesia are presented in this paper.
Case 1# is Jawa 7 Power Plant Project which is located in Baten Province of Indonesia, around 80 km away of Jakarta. The original site condition is swampy area which contains 12~14 meter depth soft clay. The original water content is more than 100% with Su 5.3 Kpa. Furthermore, there will be excavation works for main power block area in future. Geoharbour Group propose Vacuum Consolidation & Water Surcharge Method to improve the soft clay. After soil improvement works finished, the Su of soft clay increased 18~25 Kpa. The excavation become much faster and cost saving by open cut with slope 1:2 up to -7m and the excavation pit remain stable in 8 months. This innovative solutions saved a lot time and cost for the client.
Case 2# is Kalibaru Port Project which is located in north Jakarta. The existed international port of Jakarta Tanjung Priok is overload during last 10 years. Indonesia Government decided to build more terminal in the sea of north Jakarta. For protecting environment, the port authority decided to utilize all dredging material resulted by dredging water way and pond for this project to form the land. However, due the soil in seabed is marine clay, all those material become dredging slurry after be dredged and put to reclamation area. The dredging slurry is in extremely high water content and extremely soft condition which means no machines and person are able to work in that condition. The geotechnical challenge in this project is never appeared in Indonesia. The area two big challenges in this case: one is how to form a working platform and the second one is how to improve dredging slurry. Geoharbour Group proposed Double Stage Vacuum Consolidation Method as solution. The concept is: install short PVD and perform 1st Stage Vacuum Consolidation to improve dredging slurry become soft clay and form a stable working platform, after that install long PVD and perform 2nd Vacuum Consolidation with surcharge to improve soft clay to design requirement. Furthermore, There are papers indicated that there is no stable soil structure in dredging slurry which result the behavior of dredging slurry is more like mixture material between water and soil particle. This behavior will result the finest soil particle will surround the PVD if there is consolidation happened which will form an impermeable layer surround the PVD and result no further consolidation developed. The Double Stage Vacuum Consolidation Method is much more reliable solution for improving dredging slurry. This case is a very helpful case of innovative solution for reclamation by using dredging slurry.
Case 1# is Jawa 7 Power Plant Project which is located in Baten Province of Indonesia, around 80 km away of Jakarta. The original site condition is swampy area which contains 12~14 meter depth soft clay. The original water content is more than 100% with Su 5.3 Kpa. Furthermore, there will be excavation works for main power block area in future. Geoharbour Group propose Vacuum Consolidation & Water Surcharge Method to improve the soft clay. After soil improvement works finished, the Su of soft clay increased 18~25 Kpa. The excavation become much faster and cost saving by open cut with slope 1:2 up to -7m and the excavation pit remain stable in 8 months. This innovative solutions saved a lot time and cost for the client.
Case 2# is Kalibaru Port Project which is located in north Jakarta. The existed international port of Jakarta Tanjung Priok is overload during last 10 years. Indonesia Government decided to build more terminal in the sea of north Jakarta. For protecting environment, the port authority decided to utilize all dredging material resulted by dredging water way and pond for this project to form the land. However, due the soil in seabed is marine clay, all those material become dredging slurry after be dredged and put to reclamation area. The dredging slurry is in extremely high water content and extremely soft condition which means no machines and person are able to work in that condition. The geotechnical challenge in this project is never appeared in Indonesia. The area two big challenges in this case: one is how to form a working platform and the second one is how to improve dredging slurry. Geoharbour Group proposed Double Stage Vacuum Consolidation Method as solution. The concept is: install short PVD and perform 1st Stage Vacuum Consolidation to improve dredging slurry become soft clay and form a stable working platform, after that install long PVD and perform 2nd Vacuum Consolidation with surcharge to improve soft clay to design requirement. Furthermore, There are papers indicated that there is no stable soil structure in dredging slurry which result the behavior of dredging slurry is more like mixture material between water and soil particle. This behavior will result the finest soil particle will surround the PVD if there is consolidation happened which will form an impermeable layer surround the PVD and result no further consolidation developed. The Double Stage Vacuum Consolidation Method is much more reliable solution for improving dredging slurry. This case is a very helpful case of innovative solution for reclamation by using dredging slurry.
Keywords
material
Soil
Construction
Innovative Solutions
Geoharbour Group
