Reutilization of Organic and Peat Soils by Deep Cement Mixing

Authors: Bee-Lin Tang, Ismail Bakar, Chee - Ming Chan

Abstract:

Limited infrastructure development on peats and organic soils is a serious geotechnical issues common to many countries of the world especially Malaysia which distributed 1.5 mill ha of those problematic soil. These soils have high water content and organic content which exhibit different mechanical properties and may also change chemically and biologically with time. Constructing structures on peaty ground involves the risk of ground failure and extreme settlement. Nowdays, much efforts need to be done in making peatlands usable for construction due to increased landuse. Deep mixing method employing cement as binders, is generally used as measure again peaty/ organic ground failure problem. Where the technique is widely adopted because it can improved ground considerably in a short period of time. An understanding of geotechnical properties as shear strength, stiffness and compressibility behavior of these soils was requires before continues construction on it. Therefore, 1- 1.5 meter peat soil sample from states of Johor and an organic soil from Melaka, Malaysia were investigated. Cement were added to the soil in the pre-mixing stage with water cement ratio at range 3.5,7,14,140 for peats and 5,10,30 for organic soils, essentially to modify the original soil textures and properties. The mixtures which in slurry form will pour to polyvinyl chloride (pvc) tube and cured at room temperature 250C for 7,14 and 28 days. Laboratory experiments were conducted including unconfined compressive strength and bender element , to monitor the improved strength and stiffness of the 'stabilised mixed soils'. In between, scanning electron miscroscopic (SEM) were observations to investigate changes in microstructures of stabilised soils and to evaluated hardening effect of a peat and organic soils stabilised cement. This preliminary effort indicated that pre-mixing peat and organic soils contributes in gaining soil strength while help the engineers to establish a new method for those problematic ground improvement in further practical and long term applications.

Keywords: peat soils, organic soils, cement stabilisation, strength, stiffness.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1075466

References:

[1] Ongkili, M.J. (2005). " Conservation and Management of Peat Swamp Forests and Other Wetlands in Sabah: Issues and Challenges." Proceeding of the 9th Sabah Interagency Tropical Ecosystem (SITE). Research Seminar Sabah Forestry Department. Pp.215-222.
[2] Wong, L.S., Hashim, R., and Ali, F.H. (2008). "Engineering behaviour of stabilized peat soil." European Journals of Scientific Research; Vol.21:581-591
[3] Edil, T.B. (2003). "Recent advances in geotechnical characterization and construction over peats and organic soils." In 2nd International conference on advances in soft soil engineering and technology, Putrajaya 2-4 July.
[4] Hebib, S., and Farrell, E.R. (2003). "Some experiences on the stabilization of Irish peat." Canadian Geotechnical Journal; 40(3):107- 120.
[5] Huat, B.B.K. (2002). " Some mechanical properties of tropical peat and organic soils." In 2nd World Engineering Congress, Sarawak 22-25 July: 82-87 .
[6] Hernandez Martinez, F.G., and Al- Tabbaa, A (2009). "Effectiveness of different binders in the stabilisation of organic soils." In International Symposium on Deep Mixing and Admixture Stabilization, Okinawa 19- 21May .
[7] Ahnberg, H. (2002). "Report 16 : Strength of stabilised soils- A laboratory study on clays and organic soils stabilised with different types of binder" Swedish Deep Stabilization Research Centre.
[8] Hayashi, H., and Nishimoto, S. (2005). " Strength characteristic of stabilized peat using different types of binders." Proccedings of the International conference on Deep Mixing Practise, Stockolm.
[9] Yee, Y.W., Raju, V.R., and Yandamuri, H.K. (2007). " Deep Soil Mixing in Mine Tailings for a 8m Deep Excavation." In 16th SEAGC, Kuala Lumpur: 573-578.
[10] Hampton, M.B., and Edil, T.B. (1998). " Strength characteristic of stabilised peat using different types of binders," Proceeding of Deep Mixing
[11] Ahnberg, H., and Johansson, S.E.(2005). " Increase in strength with time in soils stabilised with different types of binder in relation to the type and amount of reaction products" Swedish Deep Stabilization Research Centre.
[12] Duraisamy, Y., Huat, B.B.K., and Aziz, A. (2007). " Compressibility behavior of tropical peat reinforced with cement columns." American Journal of Applied Sciences. 4(10): 784-789.
[13] Broms, B.B. (1986). " Stabilization of soft clay with lime and cement columns in Southeast Asia." Applied Research Project RP10/83, Nanyang Technical Institute, Singapore.
[14] Chen, H., and Wong, Q. (2006). " The behaviour of soft soil stabilization using cement." Bulletin of Engineering Geology and the Environmenta by Springerl.
[15] Bergado,D.T., Chai, J.C., Alfaro, M.C., Balasubramaniam, A.S. (1994). " Improvement techniques of soft ground in subsiding and lowland environment."
[16] Tan, K.H. (1998). " Priciples of soil chemistry." 3rd Edition, Marcell dekker, Inc.
[17] Nontananandh, S., Thakon, Y., and Sanupong,B. (2002). " Scanning electron microscopic investigation of cement stabilized soil." Procceding of the 8th National Convention on Civil Engineering, 2: 120-125.
[18] Filz, G.M., Hodges, D.K., Weatherby, D.E., and Marr, W.A. (2005). " Standardized definitions and laboratory procedures for soil - cement.
[19] Al - Tabba, A., Ayotamuno, M.J., and Martin, R.J. (1999). "Soil Mixing of Stratified Contaminated Sands," J. Hazard. Mater., Elsevier, B72 2000, pp.53-75.
[20] Shen, S.L., Miurra, N., and Koga,H.,(2003). "Interaction Mechanism between deep mixing column and surrounding clay during installation." Canadian. Geotechnical . Journal; 40:293-307.
[21] Horpibulsuk, S., and Miura, N. (2001). " A new approach for studying behavior of cemnet stabilized clays." Proceeding of the 15th International Conference on Soil Mechanics and Geotechnical Engineering, 3: 1759- 1762, Istanbul.
[22] Bhadriraju, V., Puppala, A.J., Madhyannapu, R.S., and Williammee,R. (2008). "Laboratory procedure to obtain well mixed soil binder samples of medium stiff to stiff expansive clayey soil for deep soil mixing simulation" Geotechnical Testing Journal, 31: 225-238.
[23] Bruce, D.A. (2001). " Practitioner-s guide to the deep mixing method." Ground Improvement,5(3),95-100.