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In 1967-1985, a research campaign comprising a unique set of long-term experimental data on concrete beams was conducted in joint collaboration with four Belgian research institutes to determine the influence of creep and shrinkage on the long-term behavior of reinforced concrete members. The main aim of the research campaign was the determination of the long-term behavior of cracking and deformations subjected to permanent loads considering the influence of the magnitude of the loads and various reinforcement ratios. The objective of this article is twofold: to provide an overview of the measured data of the reinforced beams of the research campaign, which has never been published before, and to propose a simplified calculation method based on available models in literature that can predict the available measurement data. A simplified calculation model is proposed, which accounts for nonlinear creep strains due to high stresses, shrinkage, aging, and cracking in reinforced concrete beams. This numerical method is based on a cross-sectional analysis formulated using the layered Euler-Bernoulli beam theory, allowing fast and accurate predictions of strains, stresses, and deflections as a function of time based on fib Model Code 2010 and EN1992-1-1. The measurements of the beams subjected to high permanent loads during a time period of 4 years are compared to the results evaluated with the proposed simplified calculation model. The results show that the proposed simplified calculation method based on the current models of EN1992-1-1 and fib Model Code 2010 can predict the long-term behavior of reinforced concrete beams subjected to high loads in good agreement with the measurements.

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Voronoi diagrams are promising schemes for use in architecture and structural design. Integrated into building sciences they can result in structures with a high strength to weight ratio for any material. Furthermore, such structures are aesthetically appealing. However, it is difficult to cast such structures and some teething problems are still present. In this paper a case study is presented in which a Voronoi-like tessellation was used as formwork to manufacture a small cementitious plate. Cementitious structures are not very often thin and they are susceptible to cracking. In this research, a self-healing strain-hardening cementitious material was considered as a solution to this problem. Using strain-hardening cementitious materials, it was possible to produce a thin high-strength cementitious form that could can be easily cast and demoulded. In addition, the Voronoi structure showed outstanding healing capabilities. This principle may broaden the use of these aesthetically interesting materials as design applications in the future. Notation d distance P k group of k points R k region X non-empty space Advances in Cement Research Voronoi diagrams and self-healing cementitious materials: a perfect match Snoeck and Criel Advances in Cement Research

During the period 1967-1985 the Magnel Laboratory for Concrete Research participated in an extensive Belgian research campaign with respect to the influence of creep and shrinkage on the long-term behaviour of reinforced and prestressed concrete beams. This research campaign, jointly conducted at several Belgian research institutes, comprised the investigation of concrete and reinforced concrete beams (phase 1), prestressed concrete beams (phase 2) and partially prestressed concrete beams (phase 3). The main aim of the research campaign was the determination of the long-term behaviour subjected to permanent loads, considering the influence of the magnitude of the loads, different reinforcement ratios and/or prestressing degrees and/or different cross-sectional shapes. These results were obtained by a joint collaboration of 4 Belgian research institutes, each focussing on a different reinforcement ratio and reinforcement arrangement. With respect to the reinforced concrete beams (phase 1), at each institute 12 beams were tested in a 4-point bending configuration, namely 2 static tests at 28 days and 10 long-term tests with a duration of 2 to 4 years, considering different loading levels. In this contribution some results of the reinforced concrete beams (phase 1) will be documented and analysed, comprising the results obtained on 48 reinforced beam specimens with a length of 3.4 m (span of 2.8 m) and cross-section of 0.28 m x 0.15 m. A cross-sectional calculation tool developed at our department -incorporating the current creep and shrinkage models in standards and guidelines -will be employed in order to investigate the accuracy of the available models with respect to their ability to predict the structural behaviour of the documented reinforced concrete beams.