Corrosion considerations in design and operation of rock support systems

Abstract

The selection and design of rock support systems rarely takes into explicit consideration the susceptibility of the systems to corrosion. The loss in capacity associated with the corrosion of support systems can be a major safety and economic concern in underground hard rock mines. This paper reports on the influence of atmospheric, aqueous and microbiological corrosion on the performance of support systems in several hard rock underground mines. In situ observations were complemented by laboratory investigations aiming to quantify the potential in loss of capacity of the installed support systems. A methodology is proposed to contribute to the selection and design of support systems in corrosive environments.

Behaviour of Frictional Joints in Steel Arch Yielding Supports

“…It is obvious that the friction coefficient has decisive influence on the resistance of the frictional joint and that it can also eliminate enhanced torque of the bolts. Friction coefficient is connected with a corrosion of segments (Dorion & Lassonde, 2013) and generally, it increases with the degree of corrosion. We can expect that the friction coefficient increases over time in underground conditions.…”

Analysis of in situ and laboratory corrosion coupons

“…Using a qualitative method developed by Dorion & Hadjigeorgiou (2014) for assessing corrosion severity in ground support, SMRD researchers found that rock mass resistivity data from both mines did indeed indicate that rock with lower facilitates higher levels of corrosion. This finding is shown in Figure 7, where soil and concrete resistivity guidelines along with this study's hard rock resistivity data are compared to degree of corrosivity.…”

Mining initiative on ground support and equipment: 12 years of accomplishments

“…A follow-up to the literature study, this multiphased project began by producing a detailed description of the key factors in a mine environment that serve to inhibit or promote corrosion in ground support components (Feichter 2016a). It included a questionnaire and guideline for the direction of rock and water sample taking, collection and storage at participating mine sites (Figure 9, based upon Dorion & Hadjigeorgiou 2014), which would follow under Phase 2 of the project (Feichter 2016b).…”