Multi-crack interaction in limestone subject to stress and flow of chemical solutions

• Published in: International journal of rock mechanics and mining sciences (Oxford, England : 1997) Vol. 46; no. 1; pp. 159 - 171
• Main Authors: Feng, Xia-Ting, Ding, Wuxiu, Zhang, Dongxiao
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 2009; Elsevier
• Subjects: Applied sciences; Buildings. Public works; Cracking process; Exact sciences and technology; Flaws; Geotechnics; Limestone; Mechanical-hydro-chemical (MHC) coupling; Microscope; Soil investigations. Testing; Soil mechanics. Rocks mechanics; Microscope; Limestone; Cracking process; Flaws; Mechanical-hydro-chemical (MHC) coupling; Chemical solution; Rock mechanics; Interaction; Mechanism analysis; Hydrologic condition; Experimental study; Rock mass; Ion composition; Crack propagation; Uniaxial compression; Experimental result; Corrosion; Mechanical characteristic; Coupling
• ISSN: 1365-1609; 1873-4545
• DOI: 10.1016/j.ijrmms.2008.08.001

This paper presented a number of experimental results on investigating mechanism of multi-crack interaction in limestone specimens with two or three flaws of different arrangements under the coupled uniaxial compressive stress and chemical solutions NaCl, CaCl 2 and NaHCO 3 with different ionic concentrations and pH values. The experiments were conducted on a testing system with a microscope and a CCD camera. The process of initiation, propagation and coalescence of cracks under the influence of the chemical corrosion were observed and digitally recorded. Cracking velocity, strength, cracking patterns, initial angle of new cracks and multi-crack interaction mechanism affected by chemical corrosion were also analyzed and compared with air and distilled water cases. The results indicated that the effect of chemical corrosion was quite complicated, depending on chemical ions and their concentrations and pH values, mineral components of rock, geometry and the number of flaws. The results are helpful guidance to establishing a coupling model for mechanical-hydro-chemical behavior of rocks.