Evaluation of Rock Quality of Tunnel Wall Rock Based on Rough Set Theory and Unascertained Measurement Theory

Abstract

A method for classification of the tunnel wall rock is established based on the rough set theory and unascertained measurement theory. The saturated uniaxial compressive strength, rock mass integrity index, structural surface condition, seepage measurement of groundwater, and the angle between the hole axis and main structural surface are selected as the evaluation indexes. The problem of weight coefficients for these evaluation indexes is converted into that of significance estimating on the attributes in the rough set theory. The proposed method is verified by the wall rock data of Yuanyanghui tunnel. The results show that the proposed method has an excellent performance in good agreement with the practical situation of wall rock and is feasible to classify the wall rock. Finally, the proposed method is applied to Xihualing tunnel of Zhu-Yong Expressway. The results are basically the same as those from Delphi-ideal point method, set pair analysis method, and the actual situation, which proves that the rough set theory and unascertained measurement theory are effective for classification of the wall rock.

Durability Evaluation of Concrete Bridges Based on the Theory of Matter Element Extension—Entropy Weight Method—Unascertained Measure

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Comprehensive risk evaluation of coal spontaneous combustion in goafs based on systems-theoretic accident model and processes

“…The concept of unascertained information was first proposed by Wang (1990), an academician; on this basis, the unascertained mathematics theory was established (Xiao et al 2017). The resultant unascertained measurement evaluation model is widely used in the fields of natural and social sciences (Chang and Dong 2016;Wu et al 2017;Huang et al 2018) . This model can handle indicators with uncertain information for quantitative analysis and comprehensively determine the evaluation indicators.…”

Geological Structural Surface Evaluation Model Based on Unascertained Measure

“…Let w j be the weight of X j , and w j denotes the relative importance degree of the measurement index x ij compared with other indicators, 0 ≤ w j ≤ 1, ∑ n j=1 w j = 1, where w = fw 1 , w 2 , ⋯, w n g is called the index weight vector. By using the information entropy [16] theory to determine the index weight, we obtain…”

“…Unascertained information is defined as indeter-minate information that is different from fuzzy, random, and gray information [12][13][14]. Unascertained measure theory is widely used in risk assessment in fields, such as slope risk assessment, urban environmental assessment, underground goaf collapse, enterprise innovation capability evaluation, and coal mine safety assessment [15][16][17].…”