The focus of this study was to develop a model to reproduce the behavior of chloride binding in hardened cement paste using PHREEQC based upon thermodynamic equilibrium. The equilibrium constants for Na⁺, K⁺, Cl^-, SO₄^2- were derived from the sorption experimental data using the surface complexation model for ionic binding to the surface of C-S-H. For the formation of Friedel's salt, which is considered as the chloride binding by AFm, ion exchange reaction was adopted, and the equilibrium constant of the reaction was determined from chloride sorption experimental data. Experimental data confirmed the validity of the model based upon thermodynamic equilibrium accurately predicting the binding phenomena in hardened cement paste.

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 This study investigates the temperature-dependant material property models for expansive strain and modulus of elasticity of expansive concrete using blast furnace slag cement (type B), while the authors already reported on those using ordinary portland cement. In addition, the effect of expansive concrete on controlling thermal cracking of the pier structure was numerically evaluated using a FEM program, considering the material property models obtained from this study. The results show that the presented material property models are applicable to calculate the restrained stress history of expansive concrete with mass curing temperature history.

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 This 50 years program was started at 1952. Durability of cement hardened as mortar (4×4×16cm, W/C=65%) and concrete(15×30cm, W/C=53%) has been investigating. The mortar is stored in water and the concrete is stored in water or air. The commercial or experimental cements are 13 types including High early, Ordinary, Moderate heat, Low heat, Slag, Silica and etc.. This experiment evidences cement hardened having long-term durability in strength and modulus of elasticity. Carbonation depth reached 26.3mm for High early, 45mm around for Ordinary and the center for Low heat.
　This well organized program can deriver one of the first result in the world. I deeply show respect to forerunners who promoted this program and were making constant efforts on running this program and also acknowledge to make me be the contributor.

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 In recent years, blockage accidents of coal ash in ship transportation occur in unloading by hardened coal ash. Hardening phenomena of coal ash are investigated to prevent from blockage accidents. Because blockage accidents often occur at the season of high temperature and humidity, it is assumed that the cause is moisture absorption of coal ash. Then, the cause of hardening is considered by characteristic investigation of coal ash with different coal mining areas, hardening test in the assumed transportation environment, and chemical analysis on coal ash before and after hardening. As a result, it is confirmed that the main cause of the hardening phenomena is the bridge structure of gypsum between particles. In addition, by analyzing water-soluble composition of coal ash, it is specified that the amount of SO₃ influence the degree of hardening. The amount of SO₃ in coal ash is greatly influenced by the difference of coal mining area. Moreover, it is assumed that the temperature of EP influences hardening of coal ash because it tends to be the higher amount of SO₃ in coal ash at lower temperature.

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 The trend of harmonization on chemical substances is explained with the action of harmonization in European Union(EU). At first, harmonization on characterization of waste, and horizontal project, then WEEE directive and RoHS directive, REACH and PRTR, furthermore J-Moss and Chinese RoHS are explained. They are classified to "entrance regulation/control" and "exit regulation/control". At entrance side, good results are expected by top-down force. On the other side, effect of harmonization among them may be limited at exit side. And then, harmonization will be divided into three types. The first is the harmonization from chaos, the second is the harmonization of idea and mind, and the third is the harmonization focused on market. The third type is expected in the future.

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 Ready-mixed concrete regulated by JIS A 5308 is a construction material that contributes to the foundations of modern society in every sense. Unfortunately, a few concrete structures today have been found to degrade in quality at early stage, the public's trust in ready-mixed concrete is not necessarily immovable. The problem raises numerous issues of quality-control technology, quality of the aggregate used, systems and standards for quality-assurance, the organization of the ready-mixed concrete industry, as well as commercial and contractual issues. Although many approaches have been taken to improve quality-assurance in ready-mixed concrete, the industry has been overwhelmed by the rapidly growing demand for action against deterioration of aggregate and for reduced environmental impact, as well as for clear assignment of responsibilities in law. As corporate social responsibility increases in importance, producers of ready-mixed concrete and other related parties will need to construct a new quality-assurance system bases on compliance, if they are to regain the trust of the public. It will also be necessary to clarify who is responsible for quality, improve the value of their quality-assurance, respond adroitly to changes in the social environment, and take a close look at new standards for the performance of their product.

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