Volume changes occur when soil exposed to water, for expansive soil the size of soil increases and produce pressure on surrounding area, but for collapsible soil it cause large amount of settlement under a certain load, the amount of swelling and swelling pressure can be predicted by depending on some physical properties. In order to recycling the materials of waste building demolition and stabilization soil, this research studied, the effect of adding waste building material in different

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... tages (2.5, 5, 10, 15, 20)% by the weight to the soil. The results showed that by adding 2.5% of waste building material the swell potential will decrease by 24% and the soil changes from medium to low expansive, and by adding 20% of waste building material the swell potential will decrease by 55% and soil changes from high to middle expansive. In addition, for swell pressure by adding 2.5% of waste building material, the swell pressure will decrease by 16% and for 20% of waste building material the swell pressure will decrease by 50%. On the other hand the Collapsible soil that contain gypsum showed that the potential of collapse will decrease by adding 2.5% of waste building materials by amount more than 15% and the soil changed from middle to low collapsible, the collapse potential will decrease 40% by adding 15% of waste building materials.