34 Vol.34 Supp. 2012 .11 Chinese Journal of Geotechnical Engineering Nov. 2012

12 23 4

(1. 5180552. 518036

3. 5106414. 518028)

5 GM(1,1) BP TU47 A 10004548(2012)S0063404 (1983 )E-mail: xiangw2012@126.com

Deformation predictions and control methods for excavation of deep foundation pits

XIANG Wei1,2, ZHANG Ai-jun2,3, GAO Wei4 (1. Harbin Institute of Technology Shenzhen Graduate School, Shenzhen 518055, China; 2. Shenzhen Government Investment Project

Evaluation Center, Shenzhen 518036, China; 3. School of Civil Engineering and Transportation, South China University of Technology

Guangzhou 510641, China; 4. Shenzhen Geotechnical Investigation & Surveying Institute, Shenzhen 518028, China)

Abstract: The excavation deformation of deep foundation pits is predicted by 5 kinds of different models. Compared with the

test data, the results show that the short-term prediction accuracy of the metabolic GM(1,1) model, grey Markov chain model

and BP model can meet the requirements of the engineering. But their long-term prediction accuracy is unreliable. It is proved

that the residual GM(1,1) model and the grey Markov chain model are suitable for the medium-term and long-term predictions.

The excavation deformation control methods for deep foundation pits are summarized

Key words: deep foundation pit; deformation prediction; deformation control method

0

[1-3]

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2 CJ21 Fig. 2 Field monitoring data of CJ21

3 GM(1,1) 51 -13% 12 -6%BP 46 -7% GM(1,1) BP

3 Fig. 3 Short-term prediction resluts of construction period

2

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4 GM(1,1) 16%

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4 Fig. 4 Comparison of different prediction methods

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. 637

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