Utilization of Timber Pile as a Reinforcement for Loose Sandy Soil

Abstract

Prevention of liquefaction in sandy soils can be done by increasing the bearing capacity or density through the installation of micro-piles into the soil. Utilizing micro-pile on the liquefaction prone area is quite popular to increase the soil bearing capacity. So testing the use of eucalyptus pellita timber pile as an innovation in soil repair and strengthening engineering with the liquefaction potential is expected to increase the soil bearing capacity. In this research, eucalyptus pellita timber was used as micro-piles alternatives. This study aimed to determine the effect of increasing the bearing capacity of sandy soil due to the use of timber piles. The test method used was a laboratory test by conducting a percutaneous model test on a liquefied loose sandy soil with a seismic load for 37 s, with an acceleration of PGA = 0.3 g and frequency 0.78 Hz. The test results show that the eucalyptus pellita timber pile reinforcement given to loose sandy soil can provide additional bearing capacity, as shown from the test results of the timber pile reinforcement model being able to reduce settlements that occur due to seismic loads when compared to unreinforced soil, which is equal to 68%. The results verified the effectiveness of using timber piles as a strengthening material for loose sandy soils when compared to the unreinforced model test because the presence of timberen piles functions as a shear reinforcement of liquefied soil due to seismic loads, which in turn will lead to reduced settlements.