Journal of Advanced Concrete Technology 

About: Journal of Advanced Concrete Technology is an academic journal published by Japan Concrete Institute. The journal publishes majorly in the area(s): Cement & Compressive strength. It has an ISSN identifier of 1346-8014. It is also open access. Over the lifetime, 865 publications have been published receiving 21726 citations.

Self-Compacting Concrete

Abstract: Development of Self-Compacting Concrete For several years beginning in 1983, the problem of the durability of concrete structures was a major topic of interest in Japan. The creation of durable concrete structures requires adequate compaction by skilled workers. However, the gradual reduction in the number of skilled workers in Japan's construction industry has led to a similar reduction in the quality of construction work. One solution for the achievement of durable con- crete structures independent of the quality of construc- tion work is the employment of self-compacting con- crete, which can be compacted into every corner of a formwork, purely by means of its own weight and with- out the need for vibrating compaction (Fig. 1). The necessity of this type of concrete was proposed by Okamura in 1986. Studies to develop self-compacting concrete, including a fundamental study on the work- ability of concrete, have been carried out by Ozawa and Maekawa at the University of Tokyo (Ozawa 1989, Okamura 1993 & Maekawa 1999). The prototype of self-compacting concrete was first completed in 1988 using materials already on the mar- ket (Fig. 2). The prototype performed satisfactorily with regard to drying and hardening shrinkage, heat of hydration, denseness after hardening, and other proper- ties. This concrete was named "High Performance Con- crete" and was defined as follows at the three stages of concrete:

On Engineered Cementitious Composites (ECC)

Abstract: This article surveys the research and development of Engineered Cementitious Composites (ECC) over the last decade since its invention in the early 1990's. The importance of micromechanics in the materials design strategy is emphasized. Observations of unique characteristics of ECC based on a broad range of theoretical and experimental research are examined. The advantageous use of ECC in certain categories of structural, and repair and retrofit applications is reviewed. While reflecting on past advances, future challenges for continued development and deployment of ECC are noted. This article is based on a keynote address given at the International Workshop on Ductile Fiber Reinforced Cementitious Composites (DFRCC) - Applications and Evaluations, sponsored by the Japan Concrete Institute, and held in October 2002 at Takayama, Japan.

Fiber-Bridging Constitutive Law of Engineered Cementitious Composites

Abstract: This paper is on modeling and measuring fiber-bridging constitutive law of Engineered Cementitious Composites (ECC), a high performance fiber-reinforced cementitious composite featuring high tensile ductility. Fiber-bridging constitutive law plays an important role in the multiple cracking behavior of ECC. Therefore, proper control of fiber-bridging behavior through tailoring material microstructure is the key to successfully designing tensile strain-hardening ECC. In this paper, an analytical fiber-bridging model of ECC which connects material constituent parameters and composite properties, built on a previous simplified version, was proposed. To improve accuracy of crack opening prediction, new mechanisms of fiber/matrix interactions, specifically fiber two-way debonding and pull-out, matrix micro-spalling, and Cook-Gordon effects were included. This revised model was compared with experimental measurement of fiber-bridging behavior and the validity of the model was confirmed. It is expected that this model will greatly improve ECC design technology in terms of steady-state crack width control, key for structural long-term durability, and in terms of composite tensile properties important for structural safety at ultimate limit state.

Multi-scale Modeling of Concrete Performance Integrated Material and Structural Mechanics

Abstract: Multi-scale modeling of structural concrete performance is presented as a systematic knowledge base of coupled cementitious composites and structural mechanics. An integrated computational scheme is proposed for life-span simulation of reinforced concrete. Conservation of moisture, carbon dioxide, oxygen, chloride, calcium and momentum is solved with hydration, carbonation, corrosion, ion dissolution, damage evolution and their thermodynamic/mechanical equilibrium. The holistic system is verified by the reality.

Engineered Steel Fibers with Optimal Properties for Reinforcement of Cement Composites

Abstract: Although steel fibers have been used in cement and concrete composites for more than four decades, most of the steel fibers on the market today have been introduced prior to 1980. This is in sharp contract to the continuous progress and development in the cement matrix itself. Following a brief summary of the main properties and limitations of steel fibers used in cement based composites, this paper describes the rationale and technical background behind the development and design of a new generation of steel fibers for use in cement, ceramic and polymeric matrices. These fibers are engineered to achieve optimal properties in terms of shape, size, and mechanical properties, as well as compatibility with a given matrix. They are identified as Torex fibers. Typical tests results are provided and illustrate without any doubt the superior performance (2 to 3 times) of Torex fibers in comparison to other steel fibers on the market. The new fibers will advance the broader use of high performance fiber reinforced cement composites in structural applications such as in blast and seismic resistant structures, as well as in stand-alone applications such as in thin cement sheet products.