Evaluation on the Length of Driven Pile by Using Dynamic Probing Method

Abstract

Soil exploration by using Standard Penetration Test (SPT) is an in-situ dynamic penetration test designed to provide information on the geotechnical engineering. It will be used to design the type, cross-section, size, and length of the pile using static methods. Often the designed pile length is not bedded on the desired soil layer, due to the variability of soil characteristics which increases construction cost and time. Dynamic probing is a rapid and economical ground investigation method. The purpose of this study was to determine the mathematical relation between the penetration from the Dynamic Probing (DP) and the ultimate load capacity of the pile obtained from the Hiley’s formula. In this research, data were collected on the blow count of Dynamic Probing and driving of square piles of 3 sizes: 0.35*0.35, 0.22*0.22 and 0.18*0.18 meters, with a length of 8.5-11 meters, totaling 118 piles in sand with clay and dense sand in Sakon Nakhon province. The study found that the results of the dynamic probing test are consistent with the ultimate load of piles. The penetration in Dynamic probing method can be used to assess the load bearing capacity of piles and to estimate the pile length. It was found that the DPSH-B gave the most accuracy.