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| PREDICTION OF BEARING CAPACITY OF POST GROUTING PILE IN GRAVEL LAYER BASED ON SETTLEMENT CRITERION |
| FANG Kai1，2，ZHANG Zhongmiao1，2，LIU Xingwang3 |
(1. Institute of Geotechnical Engineering，Zhejiang University，Hangzhou，Zhejiang 310058，China；2. Key Laboratory of Soft
Soils and Geoenvironmental Engineering of Ministry of Education，Zhejiang University，Hangzhou，Zhejiang 310058，China；
3. Zhejiang Province Institute of Architectural Design and Research，Hangzhou，Zhejiang 310006，China) |
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Abstract It is of great significance to determine the bearing capacity of grouted piles based on settlement criterion. The mechanism of base grouting reducing the settlement of grouted piles is analyzed. Subsequently，statistical analyses are conducted to give the distribution of bearing capacity improvement factors under different tip displacements for grouted piles rested on gravel layer. The distribution curves are approximated by normal distribution function fitted to the statistical data，and a method of predicting bearing capacity of grouted pile based on settlement criterion is presented. Then，an illustrative example and comparison of results are presented to demonstrate the validation of the method. In addition，the ratio of ungrouted pile head settlement to the pile head settlement of grouted pile at corresponding load based on the current design method is studied. The statistical data indicate that the ratio is in the range of 1–2 under a load equal to the characteristic value of design capacity，while it is in the range of 3–4 under the ultimate design load.
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Received: 13 February 2012
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2012, Vol. 31 
