Mechanical Parameters of Deep‐Buried Coal Goaf Rock Mass Based on Optimized GSI Quantitative Analysis

Abstract

In order to obtain the accurate mechanical parameters of deep-buried coal goaf rock mass, the limitation of geological strength index (GSI) in concealed rock mass is analyzed. Based on the test result and analysis of the current normative standards, the classification indexes of rock mass structural are optimized based on discontinuity distance d and rock mass integrity index K v . The ratio of rock mass saturated strength to dry strength, η, is introduced, quantization formula of structural surface conditions is proposed, and the influence of groundwater and rock types is included in structural surface condition classification. The GSI system is improved to better suit all types of deep-buried and water-rich rock masses. Furthermore, the rock mass disturbance factor D’s quantitative formula is listed according to the Hoek–Brown (HB) criterion. Taking the goaf roof under railway as an example, the parameters of deep-buried rock mass are obtained based on the improved quantitative GSI system and HB criterion. This research provides a scientific reference for achieving geological parameters and engineering designing in goaf areas.

A Constitutive Model Study of Chemical Corrosion Sandstone Based on Support Vector Machine and Artificial Bee Colony Algorithm

“…The selection of different parameters is difficult and dependent on the researcher's personal preferences because the mechanical behavior of rocks exhibits highly complicated nonlinear aspects [12,13]. Although some researchers have developed methods for quantitatively predicting rock mechanical characteristics in recent years [14][15][16], the aforementioned issues cannot entirely be avoided. New methods, for example, artificial intelligence, virtual reality, and big data, are being developed together with network technology.…”