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Title: Applicability and reliability of CYY formula based on Chinese Dynamic Penetration Test for liquefaction evaluation of gravelly soils
Chinese Dynamic penetration test (DPT) is an in-situ testing with the advantages of simple apparatus, economical test, and continuous data acquisition, especially for measuring bearing capacity, relative density and classification of gravelly soils. The typical gravelly soils sites are selected from the Chengdu Plain in China and the river bed of Echo dam downstream in the U.S., and China-US dynamic penetration testing and hammer energy measurements are conducted. The results show that: (1) The average of energy transfer ratios is 90% and the standard deviation is 7.7%, derived from 1321 energy time-history records, tested at 3 gravelly soils sites in the Chengdu Plain. The deviation is greatly affected by operation procedure. (2) The DPT test depth, using US drill rig assembling with Chinese DPT cone, can reach as much as 20 meters for assessing soil properties. (3) The average of energy transfer ratios is around 74% and the standard deviation is 8.7%, derived from 1438 energy time-history records, tested at 2 gravelly soils sites on the river bed of Echo dam downstream. The deviation is greatly affected by friction of drill rod and rope. (4) The DPT blows should be corrected according to different hammer energies. The proposed evaluation method for gravelly soils liquefaction, developed from the DPT database of gravelly soils liquefied during 2008 Wenchuan Earthquake, can be applicable for worldwide use.  more » « less
Award ID(s):
1663546
NSF-PAR ID:
10163302
Author(s) / Creator(s):
Date Published:
Journal Name:
Yantu gongcheng xuebao
Volume:
41
Issue:
9
ISSN:
1000-4548
Page Range / eLocation ID:
1628-1635
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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