Utilization of shell waste as the accelerate admixture on paving in order to improve the quality of the living environment of the kenjeran coastal community

Shells hunting by fishermen in Kenjeran coastal area, resulting waste shells which is directly dumed on beaches. It creates superficiality, coast pollution and detrimental health of coastal community due to lack of final disposal land. Waste shells are currently utilized for decorations, livestock feeds and cosmetic admixtures, precisely disproportionate to huge amount of waste shells. An experiment has been done to produce paving blocks by utilizing waste seashells through conventional machine. One paving block consists of 33% sand; 50% cements; and 17% waste shells. It indicates that paving block with 17% of waste shells powder has 38,421 MPa for the compressive strength test and smoother texture than paving block without. At present, the construction of road infrastructure is growing rapidly so there is a high demand for paving blocks. Seeing the problem of the shellfish waste found in Kenjeran Beach and the high demand for paving blocks, the design of the paving block structure using the right shell waste to be able to compete in the market will help the welfare of the coastal community of Kenjeran. The calculation of economic analysis the benefit cost analysis method is used, where the cost component is the entire cost of procuring the paving, the total cost for 10 years is Rp. 13,602,559,181. While the benefit component consists of two benefits, namely the reduction in public health benefits and paving sales revenue. The total benefit obtained for ten years is Rp. 19,850,770,548. From these values, the BCR value is 1.46, which can be concluded feasible because of the BCR value> 1. It is concluded utilisation of shell waste for paving material can be profitable for the coastal community.