Decorative light transmitting concrete based on crushed concrete fines

Abstract

The increasing demand for decorative materials among architects and designers has led to the development of various new building materials. The combination of types of functional significance was the reason for the creation of light transmitting concretes (known as LiTraCon), which are combined the light-transmitting and constructive functions. Such concrete can be used in the decorative finishing of internal surfaces and the creation of decorative products. The most common technology for obtaining light transmitting concrete based on the process of introducing oriented light-conducting fibers into the concrete mixture. This technology is complex and labor-intensive, which leads to increased cost of the material. The usage of translucent compounds instead of light transmitting fibers can enhance the mechanical properties of the material. The polymer resins introduced in the composition at formation of material interact with concrete mix and form a dense contact zone between the layers of the solidified compound and concrete. Also, introduction of composition of mechanically and chemically activated crushed concrete fines and silica fume to the complex binder could lead to further decreasing of the cost of light transmitting concrete and to improve the process of hardening of concrete mix without loss of the physical properties. Developed light transmitting concrete works as two-layered system, both components of it has similar stress and bending strength, with a dense contact zone between layers. Aforementioned complex binder was chosen to form a concrete matrix and various types of acrylic-based and epoxy-based resins were chosen to form a translucent layer. To find out the influence of admixtures on the properties of light transmitting concrete, the experimental study of physical and mechanical properties and structure of the material were conducted. The influence of type and specific surface of crushed concrete fines and silica fume on the structure and quality of decorative surface was examined. The compressive strength of concrete and adhesion between layers of concrete and translucent compound were found using the standard testing methods. The structure of concrete was examined using the methods of electron microscopy and X-ray analysis. The study of the properties of concrete shows that developed material has a compressive strength of 30 Mpa, strong adhesion of layers (destruction of material due tests goes through the matrix of concrete) and sufficient light transmitting ability.