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The common foundations adopted for these areas are installation of deep and closely spaced piles. While the piles serve the purpose well by transferring the load to a firm stratum deep down in the subsoil, the scale of machinery, materials, labour, costs and time involved are inevitably high. Sometimes such approach may prove to be uneconomical and even unwise with over-designs to counter the poor soil quality. High safety factors may be used to ensure the performance of the foundation, hence leading to the installation of deep, closely spaced piles to mobilize optimal skin friction and end bearing capacities. Floating foundations have also been used successfully in the construction on soft soils. A floating foundation is simply defined as a foundation of which the weight of the building is approximately equal to the full weight, including water, of the soil removed from the site of the building (V.N.S. Murthy, 2002). The foundation could be a raft or a mat, typically cast as a continuous reinforced concrete pad under the entire building (Carson Dunlop and Associates, 2003). Alternatively, a backfill of suitable material, as in the mass replacement method, is an option for providing a firm foundation for development on soft soils. The depth, however, should not exceed 6 m to ensure its effectiveness (J.P. Magnan, 2002). Over the years, floating foundations have undergone significant innovations with the introduction of lightweight materials, effectively reducing the tendency and risk of subsidence under the foundation’s own weight. This has made lightweight foundations a popular choice for construction on soft soils such as peat and organic soils (T.E. Frydenlund and R. Aaboe, 1997). A successful application of lightweight foundation systems was reported by the Norwegian Geotechnical Institute (NGI), where expanded polystyrene (EPS) was used as the foundation material in a housing scheme (R. Lauritzsen and J.T.H. Lee, 2002). Due to its light weight, very little pressure was exerted on the existing ground, hence minimising stability and settlement problems. The foundation installation involved excavation of the soft soil and placement of the polystyrene blocks, which then floated over the underlying ground. Nevertheless it was cautioned by B.B.K. Huat and R. Muniandy (2002) that the construction procedure requires a stable groundwater table as any changes can alter the state of buoyancy, leading to detrimental movements in the system as a whole. R. Lauritzsen and J.T.H. Lee (2002) also noted the importance of taking into account uplift pressure in a flooding situation to avoid heaving of the lightweight foundation system. For the construction of smaller structures, such as inpidual dwellings, R.P Hadmodjo (1991) from Indonesia proposed the use of the locally termed “Cakar Ayam” or “Chicken Feet” foundation system, which was first developed by Seditjamo in the 1960’s. The system consisted of a reinforced concrete slab resting on a number of reinforced concrete pipes. The soil and the pipes were modelled as isoperimetric solid elements, while the slab was modelled as an isoperimetric thick-plate element. Reportedly, passive soil pressure created a still condition of slab-pipe system, enabling the thin concrete slab to float on the supporting soils with the pipes kept in vertical positions due to the passive pressure. One prominent feature of the “Cakar Ayam” foundation system was the inside of the concrete pipes that were initially filled with in-situ soil, presumably to seal the open ends of the pipes for increased end resistance. This inadvertently increased the self-weight of the foundation, and could have offset some effectiveness of the system itself when loaded. 2. “Akar FouThe origin anwell as the “Cvocabulary, litthe extensive these extensiva formidable fIt was thoughroot-like stumimpression ofsubsurface actconcept. Theoretically construction oweight of the has not changThe “Akar Fosoil over a widthe developmeDifferent fromincorporating stumps carryiavailable but sa low price fr‘green’ value 3. ExperimenThe miniatureplywood and measuring 25the bottom of shown in Figuopen-end pipeopposed to theside views of The load test collected fromProperties of tndation”: Orind design concCakar Ayam” terally meaninroot network ve live tentaclefoundation to sht to be an apt mps beneath itf “floatation” ttivity of live rspeaking, a floof an undergrouremoved soil. ed or altered (woundation” woder area with tent of this founm the “Cakar Alightweight cing and transfsuitable produfrom manufactto the system. ntal Work e “Akar FoundPVC pipes o, 50 and 75 mf the plywood. ure 1. A pair es and the othe “Cakar Ayamthe inversed clwas simulatem Melaka wasthe soil were digin and Desigcept of the “Akfoundation syng “roots”.