In North American practice, the Becker Penetration Test (BPT) has become the primary field test used to evaluate liquefaction resistance of gravelly soils. However, this test is expensive and uncertainties exist regarding correlations and corrections. As an alternative, the 74 mm diameter dynamic cone penetration test (DPT) developed in China has recently been correlated with liquefaction resistance based on field performance data from the Mw7.9 Wenchuan earth-quake. In this study, liquefaction resistance was evaluated using DPT soundings with two hammer energies at two sites in Avasinis, Italy where gravelly soil liquefied in the 1976 Friuli, Italy earthquake. Gravel content ranged from 20 to 40% based on the 4.75mm criteria and The DPT liquefaction correlation correctly predicted liquefaction in all cases where liquefaction features were observed. These results indicate that the DPT can provide accurate liquefaction hazard evaluations for gravelly soils more economically than alternative procedures. Standard SPT energy corrections were found to be reasonable for the DPT.
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Evaluation and Optimization of Dynamic Cone Penetration test (DPT) for Assessment of Liquefaction in Gravelly Soils, Association of State Dam Safety Officials Annual Meeting
The dynamic cone penetration test (DPT) developed in China has been correlated with liquefaction resistance in gravelly soils based on field performance data from the Mw7.9 Wenchuan, China earthquake. The DPT consists of a 74 mm diameter cone tip driven by a 120 kg hammer with a free fall height of 1 m. To expand the data base, DPT soundings were performed at the Pence Ranch and Larter Ranch sites where gravelly soil liquefied during the 1983 Mw6.9 Borah Peak earthquake. DPT testing was performed using an automatic hammer with the energy specified in the Chinese standard and with an SPT hammer. In general, comparisons suggest that standard energy corrections developed for the SPT can be used for the DPT. The DPT correctly predicted liquefaction and non-liquefaction at these two test sites. Liquefaction resistance from the DPT (30% probability) also correlated reasonably well with that from Becker penetration testing (BPT).
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- Award ID(s):
- 1663546
- NSF-PAR ID:
- 10106550
- Date Published:
- Journal Name:
- Association of State Dam Safety Officials Annual Meeting
- Page Range / eLocation ID:
- 17
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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