International Concrete Abstracts Portal

the main aim of the paper is to evaluate performances of tile adhesive mortars produced with recycled glass powder as partial replacement of natural sand and calcium carbonate filler. An experimental activity was carried out in order to use glassy waste in production of pre-packed mortars for tile installation having performances comparable to those of products currently available on the market in order to reduce both the consumption of virgin raw materials (sand and limestone filler) in the industrial process and the amount of waste to landfill. Glassy waste coming from recycling of glass packaging seems to be particularly indicated to manufacture cementitious mixtures since it can act as pozzolanic material improving both rheological and physical properties of proprietary mortars for repair of reinforced concrete structures, protective and decorative coatings for walls and adhesives for ceramic tile and natural stone installation. Re-use of glassy waste, finally, has beneficial effects in terms of both cost reduction and environmental impact.

This paper discusses the use of alkali resistant cellulose fibers for decorative applications. The penetration of fibrous reinforcement for decorative concrete applications has been somewhat limited. The main barrier has been interference of the fiber during many of the intricate and complicated finishing steps employed in these high-end concrete applications. Some of the complications encountered are fibers sticking to the stamps and dragging out of the surface, fiber clumps found at the surface creating blemishes, lack of stain receptivity by the fibers, etc. These aesthetic complications can often result in customer dissatisfaction with the final product. The commercial entry of alkali resistant cellulose fibers for fibrous reinforcement in concrete has provided a new option for fiber reinforced concrete in decorative concrete applications. The potential benefits of cellulose fibers in concrete are expected to help further enlarge the use of fiber reinforced concrete in the market place.

The ready-mixed industry makes up nearly 75 percent of the U.S. consumption of cement and this represents a significant market opportunity for the possible use of wood pulp fiber in ready-mixed concrete applications. Most research surrounding cellulose fiber-cement composites has focused on manufactured products such as flat and corrugated sheets for cladding and roofing, nonpressure pipes, and cable pits. Integration of cellulose fiber into the mainstream ready mix operation for value added benefits to the concrete mix is proven in practical applications as shown in this paper. Concrete properties enhanced by cellulose fiber addition are summarized. Properties of the fiber concrete composite discussed in this paper include fiber and cement matrix bond, alkaline stability, freeze-thaw durability, plastic shrinkage cracking resistance, combustibility, fire resistance and impact resistance. The paper also highlights selected project examples demonstrating the use of cellulose fibers in concrete, such as, overlays, slab on grade, and decorative concrete.

Concrete is the most widely used building material in the world. Fortunately, concrete, especially architectural and decorative concrete, is a very sustainable material. The constituent materials that make up concrete are readily available throughout most of the world and can be collected, processed, and manufactured in an environmentally sound manner. Concrete has low embodied energy and great thermal mass that can enhance buildings’ energy efficiency. All human activities have some greenhouse gas associated with them. The electrical power generation and transportation sectors of our economy generate over 60% of the greenhouse gas emissions in the United States. The greenhouse gas emissions associated with concrete and cement’s manufacture is only approximately 1% of the U.S. total. Durability and superior life cycle are solid benefits commonly associated with decorative and architectural concrete. When using Life-Cycle Assessments conforming to international standards, concrete outperforms other building products because it conserves resources by preventing premature replacement and excessive maintenance while delivering superior service life and smaller environmental impacts than other commonly used building products. Architectural concrete is sustainable because it combines form and function in a single material. Designers and industry professionals can improve the long-term viability of architectural finishes and decorative elements by anticipating maintenance needs and designing with the future in mind.

This CD-ROM consists of 14 papers that were presented at ACI conventions in Charlotte, NC,and Denver, CO, in 2006. Selected examples of FRC applications highlighted in this special publication include slab-on-ground, jointless slabs, thin section composites, prefabricated modular housing elements, concrete buried structures, concrete infrastructure repair, fire-resistant concrete, decorative concrete, and shotcrete. Note: The individual papers are also available. Please click on the following link to view the papers available, or call 248.848.3800 to order. SP-268