PERBANDINGAN PERILAKU PERBAIKAN TANAH METODE PRELOADING VAKUM DAN PRELOADING TIMBUNAN DENGAN ELEMEN HINGGA 2D

Zakwan Gusnadi; Paulus Pramono Rahardjo; Aswin Lim

doi:10.29103/tj.v11i2.513

PERBANDINGAN PERILAKU PERBAIKAN TANAH METODE PRELOADING VAKUM DAN PRELOADING TIMBUNAN DENGAN ELEMEN HINGGA 2D

Zakwan Gusnadi, Paulus Pramono Rahardjo, Aswin Lim

Abstract

Abstrak

Perbaikan tanah lunak dengan pra-beban (preloading) dimaksudkan untuk mereduksi penurunan pada masa operasional dan meningkatkan kekuatan tanah. Preloading dalam perbaikan tanah lunak biasanya dikombinasikan dengan Prefabricated Vertical Drain (PVD) guna mempercepat proses disipasi air pori. Metode preloading dapat dilakukan dengan cara konvensional menggunakan timbunan ataupun dengan tekanan vakum. Untuk mengetahui perilaku preloading dengan tekanan vakum ini digunakan metode elemen hingga 2D menggunakan program bantu ABAQUS (berasal dari nama alat hitung Abacus). Hasil analisis menunjukan pada hari ke 217 perbaikan preloading vakum menghasilkan penurunan sebesar 1,23 m dan preloading timbunan menghasilkan penurunan sebesar 1,18 m, namun pola penurunan yang terjadi dengan preloading vakum terlihat lebih besar pada 35 hari pertama perbaikan. Pada perubahan tekanan air pori preloading vakum menunjukan reduksi tekanan air pori, sedangkan dengan preloading timbunan tekanan air pori meningkat pada masa konstruksi dan tereduksi pada masa perbaikan. Lebih lanjut pada perilaku deformasi lateral di kaki timbunan, metode preloading vakum menunjukan pergerakan lateral ke arah dalam area perbaikan sedangkan dengan preloading konvensional pergerakan lateral tanah terjadi ke arah luar area perbaikan.

Kata kunci: ABAQUS, Elemen Hingga 2D, Perbaikan Tanah, Vakum Preloading

Abstract

Improvement of soft soil by preloading is intended to lower the settlement of operation time and increasing soil strength. Preloading in the improvement of soft soil usually combined with Prefabricated Vertical Drain (PVD) to accelerate the pore water dissipation process. The preloading method can be done in a conventional way using the embankment or vacuum pressure. To find out the behaviour of preloading with this vacuum pressure, we used the finite element method 2D by using the ABAQUS support program. The result of the analysis shows on the 217th day, vacuum preloading improvement produces a settlement by 1.23 m and the embankment preloading produce 1.18 m, but the settlement pattern that occurs with preloading vacuum was seen to be greater in the first 35 days of improvement. In terms of changes in pore water pressure on vacuum preloading shows that the pattern of pore water pressure is reduced, while with pore eater pressure on preloading heap increased during construction and reduced during improvement. Further on the lateral movement behaviour in the toe of the embankment, the vacuum preloading method shows the lateral movement towards the improvement area while embankment preloading shows the lateral movement occurs towards the outside of the improvement area.

Keywords: ABAQUS, Finite Element 2D, Soil Improvement, Vacuum Preloading

Keywords

ABAQUS, Finite Element 2D, Soil Improvement, Vacuum Preloading

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References

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DOI: http://dx.doi.org/10.29103/tj.v11i2.513