Abstract: A light-weighted concrete is developed to reduce the invalid evaporation and save water in inland arid plain areas. It could float on water surface after drying and so is made into plate-like structure overlying on the water surface in reservoir. EPS (expanded polystyrene sphere) is a super-light closed particle which is stable, non-water-absorbent, and hydrophobic. It is used to replace the coarse and fine aggregates in concrete, and by adding an appropriate amount of fly ash, efficient air-entraining water-reducing agent and improving the production technique, the cohesiveness between EPS particles and cement mortar is improved. According to requirements set before the test, the light-weighted concrete with apparent density less than 500 kg/m³ and flexural strength larger than 1.5 MPa is produced. Plates made of this light-weighted concrete could be applied to preventing the evaporation in reservoirs in inland arid plain areas.

Key words: inland arid areas, EPS, light-weighted concrete, evaporation prevention, water conservation