| 摘要 |
<p>PROBLEM TO BE SOLVED: To improve the defect that conventional concrete is heavy in weight and easily cracked by impact since the concrete is constituted by kneading natural sand and cement and to economize resources by utilizing waste materials. SOLUTION: Waste plastics which can be obtained as a waste material of a building is crushed or pulverized to form protruded pellets having protruding pieces, the surfaces of the protruded pellets are coated with gypsum powder to form artificial sand for cement and several kinds of the artificial sand for cement having sizes different from each other are kneaded together with cement to form concrete.</p> |
