The cement industry is a typical "mature industry" ;however, it has always been innovative since the invention of the modern Portland cement in early 19th century. The driver for innovation has been competition both within the industry and with other alternative construction materials like steel. Ever-increasing customers demands for higher performance and quality of the products have been another driver to innovation. Through its 200-year history, the cement industry has done a great deal to reduce its environmental footprint by developing and applying advanced technology to prevent or minimize emissions of pollutants such as dust, NOx, SOx and noise.
　Through the last decade, the cement industry, especially in Japan, has been focusing its great efforts of innovation on its contribution to industrial ecology which must be an essential part of sustainable development. In 2000, the Japanese cement industry produced 82 million tons of cement. With this production, the industry used 27 million tons of waste and byproducts as alternative fuel and raw materials (AFR). The cement manufacturing process has a great advantage in using large volume of waste and by-products as AFR. This advantage mostly conies from three reasons: chemical compositions, very high temperature thermal process up to 1500℃ and no reproduction of wastes. Major constituents of cement are CaO, SiO₂, Al₂O₃ and Fe₂O₃, which are the same with those of ash from AFR. Dioxins and other organic toxic materials are safely decomposed at high temperatures in the thermal process. No new waste comes out of the cement process even using AFR. Fig. 1 shows the resource recycling flow with cement plant at the center.
　Very recently, the Japanese cement industry has advanced further towards industrial ecology with remarkable innovations, including Ecocement, Chloride Bypass, Ash Washing process, Heavy Metal Extraction and Bio-chemical Conversion of Municipal Waste into AFR. These innovative processes tremendously expand the cement industry's capability of recycling waste materials as far as to those containing chlorides (harmful to cement quality), heavy metals and dioxins. Thus, the cement industry's mission is clear: Complete utilization of the industry's capability towards industrial ecology, contributing to preservation of natural resources, prevention of global warming and extension of life of landfill sites. Now, a new word "Ecofacturing"^TM can be used for the cement industry, instead of the centuries-old "Manufacturing".

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 The incompatibility problem between superplasticizer (SP) and cement is investigated. At first, the working mechanism of SP is summarized and the important characteristics of cement affecting the performance of SP are elucidated. Then, in general, because it is not easy to control the fluctuation of fluidity properties of cement, the authors tried to prevent the incompatibility phenomena by blending several SP with different properties in this study. As SP examined, polycarboxylate SP (PC) is selected because of its diversity of performances. The possibility minimizing the differences of the demanded dosage of SP for certain fluidity and of the fluidity change with time elapse is shown by the experiments using four kinds of normal portland cement with different characteristics. In this examination, several commercial PC are blended and the behaviors are evaluated by mortar flow tests. Based on this result, one PC is specially synthesized. By comparing the behaviors of this PC and three kinds of commercial PC, the method proposed in this study is shown to be effective. This special PC can minimize the differences in the demanded SP amount for certain slump flow and the flow change with time elapse even when the fluidity properties of cement are fluctuated.

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 TAIHEIYO CEMENT CORPORATION started commercial production of Reactive Powder Composite material(RPCM) in Japan under the brandname Ductal^Ⓡ. This new material called RPCM is completely different from conventional concrete，RPCM has a wide range of application not limited to alternative concrete but extending to replacement of iron and granite. The fresh RPCM is self-compactable and its flow value achieves 270mm. The compressive and bending strength value of the hardened RPCM are 238N/mm², 46.1N/mm² respectively. In this paper, the temperature dependency of fresh and strength properties of RPCM were discussed.

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 In 1994, Richard et al. developed a cement-based material above 200Mpa compressive strength by further mixing in metal fibers to allow ductility, which gave rise to a new concept of super high-strength + high-ductility. This was named RPC (Reactive Powder Concrete) by Richard et al. from the point in which reactive powder was used.
　Based on this RPC (Reactive Powder Concrete) technology, we studied prescriptions for materials, which can be procured in Japan. As a result, we developed premixed powder consisting of several types of powder, such as cement, silica particles, special water reducing agents, and special steel fibers, which were produced commercially under the trade name Ductal^Ⓡ. This material is based on RPC, and has high added functions, such as high fluidity, the application field of which is not limited to replacing conventional concrete for bridges, etc., but extends to alternatives for steel and natural stone. From these, this new material is called RPCM (Reactive Powder Composite Material), which is different from concrete.
　In this text, we will report on the characteristics of RPCM physical properties and durability, such as shrinkage, frost resistance, neutralization, water permeability and abrasion resistance, obtained from experiments.

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 In prestressed concrete (post-tension), a PC duct needs to be completely filled up with grout to protect tense PC steel from corrosion and to unify PC steel with concrete. However it is difficult to estimate the completion of a grout practically and the technical establishment of PC grout is the important subject.
　The developed high performance PC grout is the premixed type with the powder type polycarboxylate superplasticizer (COA Flow NF-100).　Compared with conventional nonbleeding type of PC grout, it has lower viscosity and high separation resistance, so it is possible to fill up the inside of a duct completely. Moreover, it is excellent strength development and chloride isolation can expect the durability of PC structure.
　This paper describes the subject and techniques of solution in the development of high performance PC grout, and explains the characteristics of high performance PC grout in comparison with conventional PC grout.

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 Novel polycarboxylate-based liquid superplasticizers (SP1-3) are synthesized and evaluated. SP3, which has two different length of polyoxyethylene chains in one polymer molecule, shows high cement dispersion ability, good fluidity retention and short setting time.
　Polycarboxylate-based powder superplasticizers (PSP1-3) are made from SP1-3 and evaluated. PSP3 shows low moisture absorption and excellent antiblocking property.
　Fundamental properties of mortar using PSP3, such as fluidity, setting time and compressive strength are evaluated. It is confirmed that the following results.
(1) The necessary dosage of PSP3 to obtain equal fluidity is 1/10 in comparison with Naphthalene-based powder superplasticizer (NS) or Melamine-based powder superplasticizer (MS).
(2) The fuluidity retention of PSP3 is more excellent than NS or MS.
(3) The setting time of PSP3 is shorter than NS or MS.
(4) The compressive strength of mortar using PSP3 is higher than that of NS or MS.

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 The newly developed polycarboxylate-based powder superplasticizer (COA FLOW NF-100) was found to be much more suitable for premixed-products than the conventional ones. NF-100 has several advantages such as high dispersibility and excellent fluidity retention with minimal retardation. Application tests of NF-100 to grout material and self-leveling material clarified that the workability and strength improved substantially in comparison with the conventional premixed -products.
　In particular, NF-100 has excellent dispersibility when it is used in low-heat portland cement (belite-rich portland cement), and it can also impart adequate workability to premixed-products that have extremely low water-binder ratios. As a result we are able to develop unprecedented high performance premixed-products using low-heat portland cement and NF-100 such as the new pc-grout that has excellent fluidity and a high resistant ability to the penetration of chloride ions.

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 Leachability of hardened mortar made from ordinary Portland cement was estimated by using the official leaching tests of several countries. The following results were obtained. Leachate pH had a strong influence on the Teachability. During the leaching tests with acid leachates, some parts of the cement hydrates were resolved and elements contained in the cement were leached. According to the resolution of the cement hydrates, the leachate pH increased, so that solubilities of leached elements were changed. It was estimated that hardened mortar was safe in terms of teachability.

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 The optimization of "GETA (Japanese wooden footgear)" shape ultrasonic linear motor by using finite element method (FEM) and trial productions is reported. FEM was reconfirmed that it was useful for designing ultrasonic motors from the comparison the results of FEM and trial productions. The optimized motor shows 400mm/sec speed and 8nm resolution.

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 Ecocement that is made with municipal solid waste incineration (MSW) ash as a raw material has been developed. It can be classified into two categories. Normal-Ecocement and Rapid Hardening-Ecocement, with JIS (Japan Industrial Standard) R 5214 "Ecocement". Of these two categories, Normal-Ecocement with 0.1% or less of chloride ion can be used for reinforced concrete. Joint research project with Public Works Research Institute was performed for the purpose of utilizing Normal-Ecocement in a construction section from 1999 to 2001. In the joint research project, the procedures for utilizing Normal-Ecocement ware established and a "technical manual" was drawn up. This paper explains some important points on use of Ecocement in the technical manual, such as inspecting method of chloride ion content in concrete.

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