ABSTRACT

A foundation system should be known its stability performance related to adequate bearing apacity and immediate settlement. Therefore a loading test is needed to ensure the stability performance of the foundation system, no exception for Short Piled Raft foundation system as well. The loading test was conducted according to ASTM Standard D 1143 - 81: Standard Test Method for Piles under Static Axial Compressive Load. This test method covers procedures for testing vertical or batter piles individually or groups of vertical piles to determine the response of a pile or pile group to a static compressive load applied axially to the pile or piles within the group, regardless of their method of installation. Based on this standard, when the foundation has no failed up to 160% of design load, the time needed for monitoring and reading the vertical movement is 62 hours onstop. It is caused by monitoring and reading of movement at each load increment up to 1 hour with 5 – 10 minutes time interval. Whereas based on the data of loading test, the difference movement at the beginning and at the end of reading was not significant, in the range of 3% up to 15%. It was because peat has high permeability, so water could spread rapidly and made it enable skeletons became denser in the short time. Hence, there is possibility to shorten the time for monitoring and reading vertical movement at each step of load increment.

Keywords: Stability performance, Loading test, Short piled raft, Vertical movement.