Proceedings of the 30th Annual Conference on Deep Foundations, 2005, Chicago, Illinois, USA, (DFI)
Quality Control of Pile Installation Using Digital Pile Penetration and Rebound Monitoring System
Hee-suk Yun, Myoung-mo Kim, Jeong-woo Seok, Dae-jin Hwang
In this paper, the accuracy of the data measured by a newly developed displacement measuring system, DPRMs (Digital Pile Penetration and Rebound Monitoring system) and its applicability as a quality control tool were verified by field measurements of pile penetration and rebound for pile driving performed at 3 construction sites and 1 test site. The DPRMs data were found to be much better than handwork data. A new dynamic formula for pile capacities is proposed uses the results of a pilot dynamic load test and the final pile penetration. The ratios of pile capacities obtained by the new formula to those by the dynamic load test were 94%±7.4% in the contrast with 123±28.3% by the 5S formula and 68±24.0% by Hiley’s formula. This result shows the superiority of the new formula. The ratios of the maximum compressive stresses calculated by using DPRMs to those calculated using PDA (Pile Driving Analyzer) were about 90~110±10%. This result confirms the applicability of DPRMs as an over-driving monitoring tool. Two sets of DPRMs were used to measure the 3-D displacement behavior of a pile head at the test site. The more the pile head moves laterally, the less the final set values were expected because of the loss of driving energy, but this trend was not obvious within the limited data obtained at the test site.
|article #1312; publication #72 (AM-2005)|