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| Slope reliability analysis based on analytical simulation of conditional random fields of rock and soil parameters |
| JIANG Shuihua1，2，ZENG Shaohui1，PAN Jiaming1，YAO Chi1，YANG Jianhua1，ZHOU Chuangbing1 |
(1. School of Civil Engineering and Architecture，Nanchang University，Nanchang，Jiangxi 330031，China；2. State Key Laboratory of Geomechanics and Geotechnical Engineering，Institute of Rock and Soil Mechanics，Chinese Academy
of Sciences，Wuhan，Hubei 430071，China) |
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Abstract Conditional random field model can make best use of limited site investigation data to characterize the spatial variation of rock and soil properties more realistically. This paper aims to propose an analytical approach to simulate the 2D anisotropic conditional random field of rock and soil parameters. The procedure of implementation of the proposed approach is presented. A 2D conditional random field model based on the undrained shear strength is constructed and the slope reliability is updated based on the data of field vane shear tests from two boreholes. Then，an example of a clay slope under the undrained conditions is investigated to demonstrate the effectiveness of the proposed approach. The effects of the borehole location and layout scheme of boreholes on the slope reliability are also explored. The results indicate that the proposed approach can fully incorporate the limited site investigation data into the modelling of conditional random fields and realistic characterization of the spatial variation of rock and soil parameters. The obtained realizations of the 2D conditional random field by the proposed approach can reflect the inherent trends of increasing of means and standard deviations of rock and soil parameters with the depth，which make the results of slope reliability analysis more consistent with the engineering practice. The borehole locations and layout scheme of boreholes have the important influences on the slope reliability. The site specific test data acquired from the boreholes which are located in the vicinity of the slope toe can provide more value of information to the evaluation of slope reliability.
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2018, Vol. 37 
