EVALUASI STABILITAS MERCU BENDUNG BATANG TORU, KABUPATEN TAPANULI UTARA

Abstract

Weir is a barrier built across a river that is built to change the characteristics of the river flow. In many cases, a weir is a construction that is much smaller than a dam which causes water to pool to form a pool but is able to pass through the top of the weir. The material can be made of masonry, concrete or masonry and concrete. Generally it is built in the upstream and middle sections of the river. The Batang Toru Irrigation Area serves a functional area of ​​± 3200 Ha, located in Purbatua District and Pahae Jae District, North Tapanuli Regency, North Sumatra Province. The source of irrigation water comes from the Batang Toru River through a fixed weir (planned) located in Bonani Dolok Village, Purbatua District. In the construction of the weir it is still equipped with the following data: The area of ​​the river basin is 1408.4 km² and the river is approximately 75.4 km long, has a height of about + 1470.0m in the upstream part and has an elevation of + 455.0m. downstream around the weir plan location, with a discharge of Q100 = 1548.26 m³ / s. Weir stability control is by earthquake to bolster sfguling = 1.14 "≥" 1.10; without earthquake sfguling = 1.5 "≥" 1.50, against shear with earthquake shear = 2,217 "≥" 1.10; without earthquake shift = 3.27 "≥" 1.50. From the calculation control, it can be concluded that the Batang Toru Weir is safe from shear and overturning forces, which can be concluded that the soil where the weir is located can support the weir structure.