The effect of curing period and thickness of the stabilized peat layer to the bearing capacity and compression behavior of fibrous peat

Peat is soil that known as a very soft soil with high organic content, low bearing capacity, and very high compression. Soil improvement using stabilization method has been developed because it is cheaper and environmentally friendly. This paper presents the effect of curing period and thickness of the stabilized peat layer to the bearing capacity and compression behavior of the fibrous peat. This study was carried out by using physical model of the stabilized peat placed in box size of 100 x 60 x 70 cm³. Thickness of the stabilized peat layer varies: 1/3H, 1/2H and H (H=peat layer thickness). Step loading was adopted for consolidation test and each load was applied for 3 days. The results show that bearing capacity of the stabilized peat is higher than the original peat but it is slightly affected by the stabilized peat layer thickness. This bearing capacity, however, drops drastically when curing period reach 30-45 days and then keep decreasing with the increase of the curing period until it is about the same with the initial value. The compression of loaded stabilized peat layer is not only caused by the applied load but also due to the fiber decomposition. Thickness of the stabilized peat layer affects its compression where the thicker the stabilized layer, the larger the peat layer compression caused by fibers decomposition. It also shows that large compression due to bearing capacity failure occurs when the stabilized peat layer is very thin compared to the peat layer thickness.