Patlamayan-kabaran malzemenin içsel basinci altindaki komşu dairesel iki delik arasindaki gerilme konsantrasyonunun analizi

Abstract

Stress analysis for a rock medium is essential for determination of stress concentration between two neighboring circular holes and prediction of fracture behavior. When two neighboring circular holes in a hard rock medium such as granite are loaded internally by the pressure of a Non-Explosive Expansion Material (NEEM), stress concentration occurs between the holes which then causes the rock to fracture. In this study, Finite Element (FE) analysis using a Phase 2 computer code was employed to study the stress concentration between two neighboring circular holes under internal pressure induced by the NEEM. The effects of different hole diameters and spacings, rock properties and NEEM pressures were analyzed, and the data obtained from numerical analysis and statistical studies were then used to develop two models. These models were then modified by using the FE data and polynomial regression analysis. The developed statistical models were shown to be in a very good agreement with the FE analysis. Validation of the equations is only for the points located on the line passing through the centers of the holes in the elastic state. Hence, the developed models can be used with confidence to determine stress distribution and concentration factors around two neighboring circular holes, which are excavated in a hard -brittle rock and loaded internally by the pressure induced from the NEEM.