Instrumented borehole drilling for interface identification in intricate weathered granite ground engineering

作     者：Zhuoying Tan Meifeng Cai Z.Q. Yue L.G Tham C.F. Lee 

作者机构：State Key Laboratory for High-Efficient Mining and Safety of Metal Mines （University of Science and Technology Beijing） Ministry of Education Beijing 100083. China Civil and Environmental Engineering School University of Science and Technology Beijing Beijing 100083 China Department of Civil Engineering The University of Hong Kong Hong Kong China 

出 版 物：《Journal of University of Science and Technology Beijing》 (北京科技大学学报（英文版）)

年 卷 期：2007年第14卷第3期

页      面：195-199页

核心收录：

学科分类：081401[工学-岩土工程] 08[工学] 080104[工学-工程力学] 0815[工学-水利工程] 0814[工学-土木工程] 0801[工学-力学（可授工学、理学学位）] 

基　　金：the Research Grant Council of HKSAP Government and Hong Kong Jockey Club Charities Trust(No.HKU7005/01E) 

主　　题：drilling process monitoring rotary-hydraulic drilling intricate weathered granite foundation 

摘      要：The successful application in drilling for HK simple weathered granite foundation has revealed its further use in instru- mented drilling system as a ground investigation tool in the detection of other lithology formations, geohazards, underground water, and boundary of orebody. To expand the further use and test the accuracy in identification of formation, an R-20 rotary-hydraulic drill rig was instrumented with a digital drilling process monitoring system （DPM） for drilling in an intricate decomposed granite site. In this test ground, the boreholes revealed that the weathered granite alternately changes between moderate and strong. The qualitative and quantitative analysis of the penetrating parameters, indicates the effective thrust force, rotary speed, flushing pressure, penetrating rate, and displacement of the bit fluctuate at ground interfaces. It shows that the parameters get a good response with the change of rock strength at the interfaces, which can reveal the change of the intricate granite formation. Besides, a variable-slope method has been established, for identification of dominative and subsidiary interfaces in the granite site. The result from a t-test shows that the confi- dence of the instrumented drilling system in identification of the geotechnical interfaces is up to 99%.