| 摘要 |
PURPOSE: A surface layer material composition is provided to enhance draining property, elasticity and durability by using sand gathered in crushed Bonghwa stone, silt, and mud. CONSTITUTION: A surface layer material composition comprises crushed Bonghwa stone, deposition soil and mud. The crushed Bonghwa stone comprises 60-64 wt% of sand with a particle size of 10-60 meshes, 4-6 wt% of thick sand with a particle size of 4-10 meshes and 30-34 wt% of fine sand with a particle size greater than 60 meshes. The surface layer material composition is formed at a ratio of 50-75 wt% of crushed Bonghwa stone, 10-30 wt% of deposition soil, and 15-25 wt% of mud. The particle size of the crushed Bonghwa stone is 0.05-2.0 mm, the particle size of the deposition soil is 0.002-0.05 mm and the particle size of the mud is less than 0.002 mm. |
