Alireza Esparham - Department of Environmental Engineering, University of Tehran, Tehran, Iran

Concrete is the second most widely used material in the construction industry after water due to its special properties. But the Portland cement production process also has major drawbacks, with one ton of Portland cement producing almost one ton of carbon dioxide. Hence the need to use an alternative to Portland cement seems necessary. On the other hand, the principle of "waste-free" and the production of new materials with environmental impact less than the priorities will be the goals of sustainable development in future cities. To further develop environmentally friendly materials, it is necessary to know about the environmental stimuli of new materials as well as to evaluate the environmental effects of conventional materials in construction. In recent years, geopolymer has emerged as a sustainable, environmentally friendly material and an alternative to Portland cement. Geopolymers are ceramic-like materials with three-dimensional poly-compact structures formed by the chemical activation of solids containing aluminum and silica at relatively low temperatures. For the production of geopolymer concrete and use in construction, waste or by-products from industries can be used, such as coal combustion ash, smelting furnace slag, construction waste, or agricultural waste such as rice paddy. The present paper summarizes the studies on the use of geopolymer technology in sustainable materials for sustainable urban development in order to reduce the emission of environmental pollutants and evaluate the life cycle. Findings and results of studies show that geopolymer concretes have higher mechanical, chemical, and energy consumption properties than conventional concrete and offer significant environmental benefits.

Geopolymer, sustainable development, life cycle assessment, Sustainable materials