Yunus Ballim

The focus of this book is to provide guidance on the prediction of time-temperature profiles in large concrete elements during the early stages of construction, with a view to minimising the likely damage that may occur to the concrete as a result of elevated temperatures caused by the heat of hydration of the cementitious materials. Early-age elevated temperatures in concrete elements create the potential for cracking of the structure as well as compromising the strength and durability of the concrete. The book provides details on the characteristics of cementitious materials and their effects on the rate of heat evolution as well as the effects of elevated curing temperatures on the physical, mechanical and durability properties of concrete. The book also considers the effectiveness of materials selection and construction methodologies for early-age concrete temperature management and control. Several case studies are presented to illustrate the important aspects in the design and construction of temperature-sensitive concrete structures. This book is primarily aimed at practicing design and construction engineers who are concerned with thermal effects and stresses in large concrete elements. It is also aimed at researchers and postgraduate students who may consider aspects of this wonderfully complex matter of heat transfer and temperature prediction in large concrete structures, as sufficiently interesting to warrant further research and investigation.

In the period between the outbreak of World War II in 1939 and the enactment of university apartheid by the Nationalist Government in 1959, the University of the Witwatersrand, Johannesburg (Wits) developed as an 'open university', admitting students of all races. This, the second volume of the history of Wits by historian Bruce Murray, has as its central theme the process by which Wits became 'open', the compromises this process entailed, and the defence the University mounted to preserve its 'open' status in the face of the challenges posed by the Nationalist Government. The University's institutional autonomy is highlighted by Yunus Ballim in his preface to the centenary edition of WITS: The 'Open' Years. He writes: 'The emerging posture of a university willing to rise in defence of academic freedom was important because this was to become infused into the institutional culture of Wits.' The book looks at the University's role in South Africa's war effort, its contribution to the education of ex-volunteers after the war, its leading role in training job-seeking professionals required by a rapidly expanding economy, and the rise of research and postgraduate study. Students feature prominently through their political activities, the flourishing of a student intelligentsia, the heyday of the Remember and Give (Rag) parade, rugby intervarsity, and the stunning success of Wits sportsmen and women. WITS: The 'Open' Years paints a vivid picture of the range of personalities who enlivened the campus – among them some well-known figures in the new South Africa. The book includes chapters by Alf Stadler, who was Professor of Political Studies at Wits and the author of The Political Economy of Modern South Africa, and Jonty Winch, former Sports Officer at Wits and the author of Wits Sport.