Research on Determining the Load Factor for Different Types of Rocks Found in the Jiu Valley Basin in Order to Achieve Rock-Support Equilibrium in Mining Constructions

Abstract

The load factor is an important index and the philosophy of construction uses it as a tool to anticipate a potential danger of irreversible deformations of a structure. In order to achieve a classification of the possibility of a structure to yield or collapse, the minimum and maximum criteria call for the determination and evaluation of structures based on the load factor. In this article the proposed method is used to determine the maximum and minimum load factor applied to metal supports used in mining constructions. This leads to the writing of equilibrium state equations specific to the rock-support interaction. The case study consists of using data on the physical-mechanical proprieties of rocks from the Jiu Valley basin in correlation with the parameters of common metal supports. The results offer the option of categorizing, through the load factor, the behavior of a metal structure in correlation with the rocks in which it is mounted. Categorizing the dependence between the load factor and the way a metal structure takes on the load from the surrounding rock pressure can make the difference between switching or not to alternative support solutions without the permanent loss of the profiles through the occurrence of irreversible deformations, respectively reaching the point where their load-bearing capacity has been exceeded because they have entered the plastic range of use.