b. 1967
Current position: Divisional Rock Mechanics Manager, Lonmin
Qualifications:
BSc (Mining Geology) Cardiff University;
MEng (Rock Engineering) Witwatersrand University
Experience:
AD has spent his entire career working on Bushveld Complex platinum mines. He first worked at Rustenburg Platinum Mines as a geologist and rock engineer (4 years). For the last 10 years he has worked for Lonmin, mostly as head of rock engineering department. His department consists of 3 qualified rock engineers and 9 strata control officers.
AD has been involved in SIMRAC processes since 1994.
Date of interview: 2 September 2004
STATUS REPORT
1. FAMILIARITY WITH ROCK-RELATED RESEARCH WORK
1.1 How many reports have you read? Which have had the greatest impact on your work?
AD has read many research reports. He estimates that he has probably read less than half of the SIMRAC reports, and all the PlatMine reports. AD said that he had found very little in the SIMRAC research work that was relevant to the Bushveld Complex. Even those studies ostensibly focused on the Bushveld had produced little that he found useful. Perhaps the only work that he had found valuable dealt with containment support, shotcrete and thin spray-on liners.
1.2 How many workshops and conferences have you attended?
AD has attended many events, though he does not recall any as being particularly memorable. The interviewer then asked why he continued to attend them. AD replied that he goes to keep pace with developments in industry (though he is generally disappointed), and to meet people socially.
The interviewer asked if this (negative) experience was limited to SIMRAC events. AD replied that this was also his experience of SANIRE and ISRM Symposia: while there were some good papers, generally he did not feel that he got value for money. He aimed to attend one conference per year, and send people from his department along to others.
1.3 Have you supplied researchers with information?
AD said that he had done so a limited way. There have only been a few Bushveld focused projects. He had sometimes received feedback, but not always.
1.4 Have you hosted projects on your mine(s)?
See 1.3 above and 1.6 below.
1.5 N/A
1.6 Have you been a mine/industry champion for a project?
AD said that Lonmin had conducted in-house research work that had delivered useful practical results. The work was focused and site-specific. As an example of work commissioned by Lonmin, AD described the development of a support design that would allow mining at depth without the use of pillars (unmined potholes provided contributed to the support).
AD commented that some of work that he had commissioned, even though it had been well executed, had not delivered practically useful results.
1.7 Have you implemented research knowledge and technology?
AD said that he had implemented new pillar designs. The new designs had to be motivated to management, which proved to be easy as the new design allowed a higher extraction ratio with an obvious economic benefit.
AD described the introduction of a support design that “looked crazy”. It was a high density “forest” of sticks, grout packs and high strength poles that gave a support resistance of 250 kN/m2, five times the support resistance typically used in a gold mine. But it had worked!
AD said that the trust or faith of management was an important factor. The reputation for good work had been built up through a long history of success in difficult conditions - adjacent mines operating in similar conditions (Crocodile River) had failed, while Lonmin mines (Eastern Plats) had been successful.
AD said that a couple of unexpected roof collapses had recently occurred. Boreholes were drilled and samples taken and the source of the problem was identified – a weak parting about 13 m above the reef. Support resistance was increased accordingly using grout packs. However, he did not see this work as “research”, rather as sound rock engineering.
Another example of implementation was the design of a pillar free support system at mining depths of 700 – 1400 m. Potholes were successfully mapped using high resolution 3D reflection seismics. The shaft pillar and some stope pillars were designed accordingly. They comprised 8-20 per cent of the area. This ground was unmined and provided substantial regional support. Stope support was supplemented by grout packs.
1.8 Have you personally performed research work?
AD said that he had been involved in a limited way in focused, site-specific research work. He has been involved in motivating, monitoring, and implementing research.
As part of his MEng studies, AD had conducted research into strain hardening behaviour. He had recognized that some rocks encountered in Lonmin mines produced very weird test results (Poisson’s ratios >1). Thin section studies showed that this was due to microfracturing of mineral grains in a highly compressive tectonic environment. Tinus Cloete of the Council for Geoscience had tried to determine a “rock toughness index” based on thin section measurements, but the correlation with rock test data had been poor.
1.9 Have you proposed research projects to SIMRAC?
AD has been involved in SIMRAC processes since 1994, initially as a member of GAPREAG and later as a member of tripartite committees. He said that he has attended virtually all the needs analysis workshops.
AD said that he thought that “decision by committee” had caused good projects to be overlooked because they were “too site specific”. He thought that the new funding formula might produce a better outcome. AD also criticized PlatMine for sponsoring generic research that satisfied no one.
AD said that he does not wait for SIMRAC to sponsor research work when he perceives a need, but motivates it in-house.
AD commented that it is hard to come up with new ideas for research work in the current system, though it might be easier if research were more focused
1.10 What do you think of the process used to vet research proposals?
AD said that he thought the adjudication process works fairly well,. He supported a process that considered all tenders on merit rather than an automatic award of the contract to Miningtek.
AD said that he thought it could be appropriate to get international participation for some projects provided there was knowledge/technology transfer. An important criterion is the building of capacity in local organizations i.e. SA companies employing blacks.
AD said that he did not believe it was SIMRAC’s role to support a national research facility. SIMRAC should spend money in the most effective way to improve safety on mines. CSIR research is often very expensive and the work sometimes second rate, though unfortunately there are not many alternatives!
1.11 What do you think of the process used to evaluate research progress and outputs?
AD said that he thought the evaluation of research outputs was carried out reasonably well, as people assigned to review work generally took their task seriously. In some instances where local expertise is lacking, reviews by international experts could add value.
AD said that many reports had been sent back to researchers for improvement. In some cases they had even been rejected. It had sometime been necessary to make use of an independent third party (usually university professors) to resolve disputes between research organizations and the SIMRAC committee.
AD said that he believed that there were insufficient interim reviews and interaction between researchers and end-users was lacking.
AD felt that the researchers were often lazy or incompetent. By way of example he mentioned a SIMRAC project aimed at investigating the deterioration of conditions around potholes. The researchers made only 5 underground visits in a R500,000 project. Furthermore the observations and conclusions differed from the general experience of industry. The SIMRAC committee had insisted that further visits be made, where the observations were in accord with industry experience. AD mentioned another SIMRAC project where a great deal of time was spent modeling pillars, but the researcher did not make a single underground visit. And this was a R1,000,000 project!
Work directed at pillar design had also been very disappointing. The objective of the studies had been to verify the Hedley and Grant formula (1972), or develop alternatives. There has been no advance on the empirical work done by Hedley and Grant in North America.
AD attributed this to lack of thought, focus, effort, and insight on the part of the researchers. Important details were ignored. For example:
Reef strengths were averaged, even though it is known that the top 1/3 of the UG2 reef is 25% weaker than the remainder. AD said that it was important to examine data and identify trends. However, the researchers had failed to notice the differences between the properties of the UG2 and Merensky reef. AD said that it was also important to look beyond the UCS and consider the effect of confinement e.g. using the Hoek-Brown failure criterion.
RMR was used to characterize the rock mass. While RMR has its place, the researcher needed to step back and understand the actual problem. In this case the main factor affecting stability was not joint density, but the angle of the joints leading to wedge formation and the shearing of the top reef contact. The researcher failed to appreciate this, and merely sought to apply a simple recipe. Consequently the project failed to bring new insights.
AD said that there was insufficient feedback to practitioners on the mines during the course of a project. Often there would be a single interim report, followed by the final report. Then it was too late to remedy any shortcomings.
AD commented that while he appreciates that research findings must be backed up with data, some reports are ridiculously long e.g. a SIMRAC report on stabilizing pillars comprised 7 volumes.
1.12 How could the SIMRAC research program be improved?
AD said that he thought there had been a big improvement in SIMRAC efforts during the last few years, but it was still quite weak. If it were up to him, he would terminate SIMRAC and direct the money and effort to university-based research. Alternatively, each mine could be compelled to spend an amount equal to their levy on relevant research.
Given that SIMRAC is here to stay, AD made the proposed the following course of action. He said that he thought that enough generic work has been done. He proposed that 10-20% of the budget be spent on fundamental research, and the balance on implementation. By this he meant work that focused on a particular problem in a mine e.g. pillar design. AD remarked that pillars remain a problem as bursting still occurs. AD believes that a lot of the blame lies with the mining companies who continue to apply the Hedley and Grant formula to the Bushveld Complex even though it was empirically derived in a completely different environment (Elliot Lake, Canada).
AD said that he believed that there was substantial scope to advance rock engineering practice on mines as it was generally characterized by poor management and ignorance. As an example, AD said that the three qualified rock engineers in his department worked hard, but did not have the capability to advance the science. This was not their fault as they had come from production positions and lacked tertiary education. Their background was more suited to strata control work. AD said that it is difficult to attract bright young graduates capable of conceptual thinking to the profession. AD said that he believed mining companies were at fault, as they tended to prefer candidates with practical mining experience (e.g. shift bosses) to graduates. He commented that it was probably easier in the past to accommodate a research position or “graduate in training” as rock engineering departments were larger. Now each shaft wants to have a dedicated practitioner.
AD said that tripartism does not work at all. There has been virtually no participation by labour, except for a period when they employed a retired senior practitioner, Roger More O’Ferrall, as their representative. Government has a single representative. AD believes that there should be worker input and that the government input should be strengthened. AD said that he thought that Duncan Adams, the SIMRAC programme manager, gave sensible independent input.
AD advocated focused rather than generic research, giving “real answers to real problems”. AD said that Lonmin had embarked on self-funded research because of dissatisfaction with SIMRAC and PlatMine.
AD said that he believed that SIMRAC had been reasonably well managed since Duncan Adams had been appointed.
2. IMPACT OF ROCK-RELATED RESEARCH WORK
2.1 Has research work enable you to do your work better?
AD said that he had received very little benefit from SIMRAC or PlatMine projects. The only exceptions had dealt with containment support, shotcrete, and thin spray-on liners. He had benefited substantially from work commissioned by Lonmin.
2.2 Has research work improved safety in the SA mining industry? /on your mines?
AD said that while there had been an increase in knowledge, he could not see much impact. New technologies that had made an impact (e.g. pre-stressed elongates) were the result of product development rather than research. He mentioned that SIMRAC projects had verified some work carried out prior to the start of the SIMRAC programme such as preconditioning.
2.3 Has research work improved safety on your mines?
See 2.1 above.
2.4 How would you describe the research work carried out by SIMRAC?
AD agrees that the SIMRAC work is academic in nature.
While many projects were scoped to be practice-oriented, few actually proved to be so.
AD said that while projects are supposed to be safety focused, they haven’t delivered much.
AD considers only a few projects to have been productivity focused.
AD disagrees with the statement that the work is “highly sophisticated”, though agreed that some good work has been done and that might be on a par with international work.
2.5 Are research products effectively transferred to practitioners?
AD said that very few projects had delivered outputs that could be practically implemented. He believes that the blame lies mostly with researchers for not coming up with practical solutions, though it may also be due to the scoping of the projects. Perhaps the objectives were unrealistic.
AD said that the early days of SIMRAC were a disaster, producing a mountain of paper that sits on shelves gathering dust. More recently there has been a drive to produce small handbooks, but very little has been applicable.
The SIMRAC Handbook and Textbook are “nice to have”. AD encourages his staff to use them as study material. However, they are primarily focused on gold mining. AD finds the pillar design chapters particularly disappointing.
AD said that he thought the SIMRAC workshops were generally good.
2.6 Are practitioners able to effectively implement the research?
(a) Software:
AD said that the Support Design software (SDA) was “a pet hate”. He does not believe or trust the results, and will sooner use the J-block program. He is not interested in energy absorption, and believes that key-blocks are far more important.
AD said that there is a tendency for many projects to have a software package as an output. There is a risk that practitioners will simply plug in numbers and not use their brains. Here he blames the practitioners for wanting a recipe and the researchers for supplying it. AD said that he thought that this was a problem with the industry as a whole.
(b) Hardware:
AD said that he thought that the continuous closure meters might prove to have some use.
(c) and (d) Concepts and theoretical solutions:
AD said that apart from the work on shotcrete, he has not gained much.
2.7 Have SIMRAC funds been well spent?
AD said that he did not believe that there had been value for the money spent. Only a limited amount of work had focused on the Bushveld Complex. There has been little increase in understanding, and there certainly have not been any results delivered.
AD had much the same opinion of the PlatMine efforts: “there had been a few good things produced, but not many”.
FORESIGHT REPORT
3 What changes do you predict will affect the SA mining industry during the next decade?
AD expressed concern that the availability of skilled practitioners will diminish. The situation is already getting worse. There is a serious lack of mentorship on the mines. This has been brought about by decentralization. Each shaft is seen as a business unit. It is no longer possible to wander into the boss’s office to chat about a problem. AD said that he would like to sign on a high-caliber graduate rock engineer in training, but his request has been turned down. Mines, with their focus on costs, are looking for a “body on the shaft”.
AD said that many rock mechanics departments had been closed down and the work outsourced to consultants.
AD said that the lack of a tertiary qualification in rock engineering (at SA institutions) meant that on-the-job training was critical.
AD remarked that there is a huge amount to see on the mines. A good enquiring mind is required. Researchers should get underground more often.
4. What advances could significantly address the above-mentioned changes?
AD said that it would be good to see CSIR researchers seconded to mines. They could be given a problem to work on for, say, 6 months. The mine should get an answer to their problem and the researcher will get an understanding of practicalities.
The interviewer asked if expert system could possibly help address the skills shortage. AD replied that he is not a fan of expert systems, as mining is inherently complex. Neither is he a fan of design charts – while they have their place, they are widely abused!
5. What advances could significantly reduce rock-related safety risks?
AD said that he believed that the biggest problem in Lonmin mines is non-adherence to standards, sometimes even a flagrant disregard. AD said that he believed that it was “in our nature”. People believed that “rules are meant to be broken”. AD We see this attitude in the way we drive – people jump stop streets and break speed limits. AD said that very different attitudes prevail in Europe and Australia. He noted that these mines are usually quite different (steep vein, open stopes, highly mechanized with remote control bogging at draw points). However, we must find an acceptable level of risk as mines in the UK had been “legislated almost out of existence”. Consequently, advances with regard to behavioural issues could be a big driver that could improve safety. AD said that it would be a fantastic result to cut fatal accidents could by 25%. This could be achieved by doing the basics of mining and rock mechanics (pillar design and support) right.
A second area for improvement was the support of overstressed tunnels e.g. a reliable methodology for designing shotcrete liners.
Face area support remains an ongoing problem. Barring and examination of the hanging wall is not always done properly. A walking beam rockfall prevention system (Pretoria U/Grinaker) is currently on trial at Eastern Platinum. This could be an expensive solution. AD supported ongoing research for a cost-effective face area support system e.g. roof bolting.
6. What factors could improve rock-related safety?
AD ranked the factors as follows:
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Better training of in-stope workers AND better supervision AND stricter enforcement of regulations and codes of practice. AD commented that one of the reasons that Lonmin does better than it’s neighbours is that they have a good training stope.
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Techniques to detect hazardous structures ahead of mining
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Greater mechanization, thereby removing workers from hazardous areas. AD advocated a change from the current drill and blast mining technique that exposes fresh hangingwall daily
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Implementation of existing knowledge
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A quantum improvement in support systems
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Stress modeling techniques that accurately simulate rock degradation and failure. AD said that they already have packages that they don’t use to maximum potential
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The ability to predict reliably the occurrence of rockbursts in space and time is not relevant to Lonmin mines
7 NEED FOR ROCK-RELATED RESEARCH
7.1 Should research work continue in SA
AD said that there is definitely a need for research, but not of the type that has been done for the past decade.
7.2 Should research effort be increased significantly?
AD said no.
7.3 Do we have the research competency?
AD said that he did not believe that there was local competency to do research in the Bushveld. His first two choices were based overseas (Steve Goddin, Andy Haile), though both had worked in SA. They have the ability to deliver results that he can trust and implement.
7.4 Do we have the research capacity?
AD said no.
7.4 Do we have the research facilities?
AD said that the facilities are fairly good, and he is quite happy to use local facilities for testing of rocks, sticks and packs. AD expressed some concern regarding the CSIR rock-testing labs. They were always seen as first choice, but he had recently discovered a glitch in the computer programme used to calculate Young’s modulus – the line was forced to run through the origin.
7.6 Should the focus be on implementation rather than on more research?
AD agreed.
7.7 Should research work be abandoned?
AD disagreed with the proposition, saying that there is always a need for research. AD said that he thought that more should be done at universities
7.8 Would stricter enforcement have a greater impact than more research work?
AD agreed strongly with the proposition. He said that he had looked at plenty of accidents, and that 80% were due to blatant adherence to standards.
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