摘要：It has been a long time that red bricks become the raw material for wall compilers. As the era develops, the bricks that are light, easy to compile and not time-consuming in manufacturing are invented. The composition materials for the building blocks are cement, sand and water. In this study, the use of sand in the bricks is reduced with LDPE plastic pellets. The reason for the use of LDPE plastic pellets as substitution of plastic materials is that LDPE plastic pellets have smaller density than sand does, so that it is expected that the brick becomes lighter although consists of the same composition and it can also reduce environmental problems as LDPE plastic waste is difficult to be decomposed by nature but gradually produced by humans that results in excessive waste The LDPE plastic pellets utilized are used LDPE plastics that are recycled into plastic pellets. The sample in this study consists of cylinder with diameter of 15 cm and height of 30 cm as sample of trial mixes test, concrete bricks with size of 40 cm x 20 cm x 10 cm, cube with size of 5 cm x 5 cm x 5 cm and briquette. The trial mixes samples will be treated for 7 days and the brick, cube and briquette samples will be treated for 28 days prior to testing. Furthermore, the sample will be tested with visual, content weight, absorption, compressive strength and drag strength tests. The data analysis uses SNI 03-0349-1989 reference on Concrete Bricks as The Matching Composition for Walls. This study used a mixture of cement, sand and water with ratio of 1: 6: 0.24, this composition was obtained from experiments on several specified compositions. The composition of substitute of plastic pellets used is 20% to the sand, the composition of this substitution is obtained from the experiments on several specified compositions. From the visual appearance, the content weight and absorption, both of normal brick and 20% LDPE pellets are included in the quality I, while the compressive strength test against the sample of normal brick results in quality I and 20% LDPE pellets brick results in quality III.
