Creep And Shrinkage

Today research on creep and shrinkage of concrete is diversified to such a degree that specialists working in different areas sometimes find it difficult to understand one-another. Materials scientists are mainly interested in processes on a microstructural level but they do not necessarily understand the relevance of time dependent deformation in structural design. On the other hand engineers who apply simplified model laws in non-elastic structural analysis are not always in the position to judge the limitations implied in their approach. It is generally realized that further development can be stimulated by a more effective exchange of results and ideas among the different groups involved. In an attempt to bridge this obvious gap in September 1980 there was a Conference organized at Swiss Federal Institute of Technology in Lausanne. The papers presented at this meeting covered the wide range starting with microstructural aspects and mechanisms and including constitutive modelling and structural creep analysis. These contributions together with summaries of two panel discussions are being published in this volume. All serious of the meeting have been introduced by invited lectures. These papers will be published in a special volume "Creep and Moisture Effects in Concrete". This special volume is rather to be a general survey of the different areas covered while the present conference proceedings provide a unique selection of research papers. Nowadays time-dependent deformation of concrete can be taken into consideration realistically by computerized structural analysis.

This book is based on Reinforced Concrete-Prestressed Concrete, Volume 2, Accounting for the Effects of Creep and Shrinkage on the Behavior of Structural Systems by Hubert Rusch and Dieter Jungwirth, which appeared in German in 1976. Even then, it was Hubert Rusch's fervent wish to have his thoughts on the deformations of concrete translated into English in order to reach a wider audience. His earlier efforts to contribute a study to the Series of Monographs of the Ameri can Institute had unfortunately not succeeded. Despite a serious illness, Hubert Rusch undertook, with his characteristic prudence and thoroughness, the preparatory work for the translation and related revision of his book. Unfortunately fate did not grant him the satisfaction of seeing his work completed. Hubert Rusch died on October 17, 1979. In writing this book, Hubert Rusch drew on his many years of devoted study of the creep problem. These investigations go back to 1934. His awareness of the plastic deformation of concrete under sustained load, which had been reported to him on the occasion of an American sojourn, led him to discover the causes of a major building collapse. At his urging, Professor A. Hummel published, in 1935, a critical survey of the test results then available on concrete creep.

This comprehensive treatise covers in detail practical methods of analysis as well as advanced mathematical models for structures highly sensitive to creep and shrinkage. Effective computational algorithms for century-long creep effects in structures, moisture diffusion and high temperature effects are presented. The main design codes and recommendations (including RILEM B3 and B4) are critically compared. Statistical uncertainty of century-long predictions is analyzed and its reduction by extrapolation is discussed, with emphasis on updating based on short-time tests and on long-term measurements on existing structures. Testing methods and the statistics of large randomly collected databases are critically appraised and improvements of predictions of multi-decade relaxation of prestressing steel, cyclic creep in bridges, cracking damage, etc., are demonstrated. Important research directions, such as nanomechanical and probabilistic modeling, are identified, and the need for separating the long-lasting autogenous shrinkage of modern concretes from the creep and drying shrinkage data and introducing it into practical prediction models is emphasized. All the results are derived mathematically and justified as much as possible by extensive test data. The theoretical background in linear viscoelasticity with aging is covered in detail. The didactic style makes the book suitable as a textbook. Everything is properly explained, step by step, with a wealth of application examples as well as simple illustrations of the basic phenomena which could alternate as homeworks or exams. The book is of interest to practicing engineers, researchers, educators and graduate students.

CREEP, SHRINKAGE AND DURABILITY MECHANICS OF CONCRETE AND CONCRETE STRUCTURES contains the keynote lectures, technical reports and contributed papers presented at the Eighth International Conference on Creep, Shrinkage and Durability of Concrete and Concrete Structures (CONCREEP8, Ise-shima, Japan, 30 September - 2 October 2008). The topics covered

This collection contains 59 peer-reviewed papers on concrete and concrete structures presented at the Ninth International Conference on Creep, Shrinkage, and Durability Mechanics (CONCREEP-9), held in Cambridge, Massachusetts, September 22-25, 2013.

This new edition of a highly practical text gives a detailed presentation of the design of common reinforced concrete structures to limit state theory in accordance with BS 8110.

The use of composite structures in construction is increasing. The optimized combination of the two materials concrete and steel produces particularly cost-efficient structures. This book presents a large number of numerical examples with detailed explanations of the provisions of Eurocode 4. It deals with the most common structural components in building construction: beams, columns and slabs. Furthermore, comprehensive chapters provide insight into the topics of creep and shrinkage, as well as fatigue. This book enables the reader to efficiently perform analyses of composite structures. It is a valuable reference book for professionals as well as an outstanding means for students to become familiar with the Eurocode 4.