Use of DYWIDAG Bar Anchors for the Construction of an additional Overflow Spillway at Soyang Dam

Construction of 2 spillway tunnels for the Soyang Dam

The Soyang River raises in the Sulak mountains and ranks among Korea's most famous sightseeing attractions. About 250 km north of Seoul the Soyang River dammed up by the Soyang Multipurpose Dam built between 1967 and 1973 is one of the largest reservoirs in the Far East. Because of the area’s beautiful scenery, a tourism and recreation area has developed around the Soyang Lake. Many people like to go there on daily excursions. Because of its dimensions, the Soyang Multipurpose Dam is a milestone in Korean civil engineering and construction.

The dam is 123 m high, 530 m long and has a volume of 9,600,000 m³. The reservoir holds 290 million m³. The electric power station at the base of the dam has a capacity of 200,000 kWh. To avoid possible floods caused by unusually heavy and long rain falls an additional overflow spillway had to be built. Therefore, the owner of the dam, Korean Water Resources Corporation, decided to build additional discharge or spillway tunnels. The new spillway consists of two side-byside tubes with a diameter of 14 m each. The tunnels have lengths of 1,276 m and 1,206 m respectively with a gradient of nearly 100 m. This way, an additional 6,700 t water per second can be discharged through a total of four new flood gates.

The discharge of the two new spillway tunnels is located in a very steep slope that had to be stabilized elaborately. DSI Korea supplied a total of 296 DYWIDAG Bar Anchors Ø 32 mm. In addition, DSI Korea provided the equipment for grouting and stressing as well as technical assistance.