1. Introduction

The last few years brought an upsurge, if not a leap, in the concrete technology. As a result, the technological conceptions of the new generation concrete appeared, such as, for example:

 

  • high - grade concrete with high durability on aggressive environment, its design based on microstructural and mechanical models,
  • "environmentally friendly" concrete - characterised by the low energy - intensivty and low emission into the atmosphere, which enables the management of the industrial waste or even the immobilisation of toxic compounds in the wastes,
  • "human - friendly" concrete, which improves the working conditions, eliminates the simplest tasks on the building - site, is silent and aesthetic.

The key role in all those conceptions play the cementitious binders, and the one of the most important direction in their development is the usage of mineral additions which are available mostly as the by-products of the industrial processes.
The use of the mineral additions not only improves the concrete properties (particularly in the aspect of enhancing their durability on aggressive environment), but also enables to procure a number of ecological benefits, mainly such as a reduction of CO2 emission, saving up the natural resources, reducing the energy used in concrete and cement production, more effective waste managing that leads to reduction of, i.a., the disposal sites' area and the costs of disposal. Because of that, the use of mineral additions contributes to the balanced development strategy, which is, to the great extend, determining the future economic development.
The most commonly used mineral additions to the cements and concrete is a silicium fly ash, produced in the process of the bituminous coal combustion in the conventional hearths, ground granulated blastfurnance slag and silica fume. In Poland over 30% of the electricity is produced from the combustion of the bituminous coal in the conventional hearths. In the process about 4 mil. Mg of the high - calcium fly ashes are produced. This kind of the ash distinguishes itself form silicium fly ash with the richer chemical and mineral composition. Its most characteristic features are the high content of the free calcium and sulphur compounds, as well as the considerable inconstancy of the composition and aggregate constitution in time, even in one power station. The constitution of the fly ash provides it the pozzolanic - hydraulic properties. The high - calcium fly ash is mentioned in cement standard PN - EN 197 - 1 as a pozzolanic addition used for the production of cement. The high calcium fly ashes' properties are also the subject of standards and technical specifications concerning the number of other technological solutions in production of the building materials. According to the standard PN-EN 206-1 „Concrete part 1: Specification, performance, production and conformity" in constructive concrete technology can only be used silicium fly ashes that fulfil the requirements in standard PN-EN 450 - 1 "Fly ash for concrete - Part 1: Definition, specifications and conformity criteria" for the active type II addition for concrete. This standard do not mention the high - calcium fly ashes. It cannot be ruled out, that due to the research over the use of such a fly ash the situation could change.
In Poland, high - calcium fly ash is practically out of use in cement and concrete technology. The main reasons for this situation could be listed as following:

  • above - mentioned characteristic of the composition, meaning the high content of free calcium and sulphur compounds, which could have potentially negative impact on the concrete,
  • extremely high fluctuation of material quality, connected with inconstancy of the chemical and phasic composition as well as aggregate constitution, 
  • favouring use of the silicum fly ashes both in the cement industry and the concrete technology,

It should be noted, that only relatively few research and development works on the topic of the use of the high - calcium fly ashes as type II addition to the concrete has been conducted as yet. It results in extremely restricted access to systematic research results that formulate comprehensively the effects of use of the high - calcium fly ashes in the concrete, especially concerning the durability and experience with practical uses. Conducted wide literature research [1-37] and the analysis of existing documents of reference (standards and technical approval) had shown that the material in question could be the main ingredient of cement (high - calcium fly ash W as defined by standard PN-EN 197-1:2002), type II addition to the concrete (American standard ASTM C618, Canadian standard CAN/CSA-A23.5-98) and the basic ingredient in binders used for stabilising the soil, reinforcing the subsoil and other works in road - building. To achieve that, it is however needed to conduct the full cycle of research in the order to develop the production technology of cement production technologies that use the high - calcium fly ash as the main ingredient and defining the extend of the use of such cements in civil engineering. Systematical tests to determine the capabilities and conditions of the most effective use of the fly ashes in question as the additions to concrete is also essential.
The conducting of this task has been undertaken by "Smart Concrete" Consortium, consisting of three institutions: Silesian University of Technology - as the leader, Institute of Ceramics and Building Materials in Warsaw, Department of the Institute - Department of Glass and Building Materials
in Cracow and Institute of Fundamental Technological Research Polish Academy of Sciences in Warsaw. Above -mentioned institutions specialize in experimental and applicatory research, have a lot of experience in the conduct of innovative research in the field of building binders' and concrete technology as well as have on disposal highly qualified research and development personnel with specialist research infrastructure.
In 2009 the Consortium made a motion for financing the project titled : „Innovative cementitious materials and concretes made with high - calcium fly ashes" from the founds of the Operational Programme - Innovative Economy, Priority 1: Research and development of new technologies, Measure 1.1.2 Strategic programmes of scientific research and development work. The motion was recommended for financing by the end of the year 2009, and from the year 2010 the research and development works were initiated. In following paper outlined are the objectives, scope of research, assumptions, the research schedule as well as its anticipated impact.