Civil Engineering October 2022 | Vol 30 No 9

C oncrete will always be extensively used in every civil and construc- tion project. It is durable, versatile and suitable for many applications in different environments. But if the cor- rect concrete practices are not followed, concrete works could become nightmares and costs could soar totally unexpectedly and unnecessarily. John Roxburgh, Senior Lecturer at Cement & Concrete SA’s School of Concrete Technology recommends that public and private sector employers identify suitable people on their staff and “champion” them to become their concrete supervisory specialists. “Site control is vital to getting con- crete works done correctly and on time. Sound concrete technology knowledge at supervisory level will ensure that concrete operations run smoothly. The skills required to transport, place, compact and cure concrete should be taught and con- trolled by a competent supervisor who has had proper training. He or she would spot potential problems at an early stage, facili- tate good concrete practice, and produce a quality concrete product,” he says. “Without staff with training in concrete technology, so many things could go wrong on site. Plastic shrinkage, settlement and thermal cracking, blow holes, honeycombing, drying shrinkage cracking, dusting, streaking, discoloura- tion, inadequate compaction, strength and curing, high permeability, cold joints, loss of cover, and lack of abrasion resistance are just a few potential problems. Cement & Concrete SA encounters these problems repeatedly when visiting sites, and yet they are all easily preventable with basic concrete technology knowledge.” Roxburgh says in a lifecycle analysis of a structure, maintenance and repair are major contributors to the overall cost of the structure. “This is where a detailed knowl- edge of concrete technology will enable a professional to build a cost-effective, durable and low maintenance structure according to its location and environment. Neglecting this will lead to escalating costs later and huge maintenance demands. Property and infrastructure owners with access to a pro- fessional with extensive concrete technology knowledge have a distinct advantage when it comes to lifetime costing.” In recent years, the importance of con- crete durability has become paramount. Specifications for durability are now being written into South Africa’s national stan- dards and many state institutions are in- sisting on durable concrete structures. The many South African municipalities lagging with the implementation of durability requirements are probably without suitable concrete expertise in their employ. “In any event, at both advanced and more basic levels, the School of Concrete Technology has always advocated a stepped approach to education. All our courses are set at different standards of competency and knowledge. A student should start at an appropriate level to not miss out on im- portant key concepts and practices. Then, having successfully completed a course, a reasonable amount of time should be given to acquiring appropriate practical experi- ence in industry. In this way, the student will obtain a holistic concrete technology education which makes him or her much more valuable to the concrete industry and national economy,” says Roxburgh. When selecting a training provider, Roxburgh says it is important to ensure that the provider is experienced in providing up-to-date, relevant concrete technology education. The training pro- vider should also issue certificates that are well recognised within the concrete and related industries.  John Roxburgh Senior Lecturer Cement & Concrete SA School of Concrete Technology john.roxburgh@cemcon-sa.org.za Serious shortage of trained concrete technologists Many South African municipalities and state bodies entrusted with infrastructural and building developments still have limited technical concrete knowledge on call from within their own ranks. Spotting potential problems, facilitating good concrete practice and producing a quality concrete product can only be done with adequate training. 16 October 2022 Civil Engineering