EFFECT OF ROAD’S SLOPE ON THE EFFICIENCY OF THE RAIN STORM DRAINAGE NETWORKS

The frequent rainfall has increased recently especially in arid region due to global warming. This phenomenon caused a set of problems such as disruption of traffic and increasing pollution due to stagnation of water. This paper deals with the experimental investigation of the storm network drainage system efficiency by changing longitudinal and side slopes of the roads. The altering of road slopes has been done through two stages: the first stage, Six side slopes (1.5%,2%,2.5%,3%,3.5%,4%) are used with constant longitudinal slope 0.3% and the second stage, five longitudinal slopes (0.3%,0.4%,0.5%,0.6%, 0.7%), are used with constant value of side slope 3%. The results indicated that as the side slope increases the efficiency of discharge increase, where the efficiency increased by 10% as the side slope increase from 1.5% to 4%. Also from second stage, the results showed that as the longitudinal slope increases the efficiency of discharge decrease, where the efficiency by 5% as the longitudinal slope increase from 0.30% to 0.70%. In addition, the results specified that Change in the road side slope has a significant impact on storm drainage efficiency than road longitudinal slope.