Earthquake-resistant design for Dam prototype, the result of innovation design by ITS’s Tirta Gangga team 

ITS Campus, ITS News – Construction of dams assessed highly needed to ensure water and food security in Indonesia. Looking at Indonesia’s condition that is prone to earthquakes, the team from Institut Teknologi Sepuluh Nopember (ITS) designed an earthquake-resistant dam design using the Morning Glory-type.

The team from the Department of Civil Engineering ITS consisted of Irfananda Setiadi Hutomo, Ahmad Wisam Abdillah, Faisal Emir Yusuf. With the name of Tirta Gangga, chose to use the Morning Glory because the type of spillway is still very rare in Indonesia. Spillway itself is a complementary building on the dam whose function is to drain excess water when flooding occurs, so that water is not abundant beyond the dam body.

Mohammad Bagus Ansori ST. MSc, the team’s mentor and their lecturer revealed that the excellence of the Morning Glory type is considered suitable for implementation in a location that does not have enough space for the spillway. Also, the overpass of Morning Glory utilizes the drain tunnel as a water production channel.

Based on the cost analysis, he continued, the tunnel is assessed to be more affordable in the construction of spillway. “It’s more than the side-down that requires a transition channel and the launcher is long enough at the study site,” says the man who often called Bagus. The location of the study is located in West Nusa Tenggara (NTB) area.

For information, until today the number of large dams in Indonesia has reached 231 dams and will be built 65 new dams again until 2023. As explained by Bagus, the design of the dam itself is declared as earthquake-resistant design when it has qualified related stability control of the dam body. Based on the calculation of stability control with the prevailing earthquake coefficient in Indonesia, the body of the dam has received a safety factor in the above 1.5. “If the structure is above 1.1 it is safe,” said the lecturer from Kediri.

(left to right) Mohammad Bagus Ansori ST. MSc (Mentor Lecturer), Ahmad Wisam Abdillah, Irfananda Setiadi Hutomo, Faisal Emir Yusuf who joined in Tirta Gangga team

Furthermore, Bagus explained, dam design of this team is planned to have a multipurpose goal for raw water, hydroelectric power (HYDROPOWER), irrigation, and flood controllers. Therefore, the design also utilizes solar power panels that are placed in the body of the dam. Hopefully, the panel can be enabled as an independent electrical operation in the area of NTB. “So it can reduce operational costs related to electricity needs in the dam site,” said Bagus.

Bagus claimed that the design of the dam designed by his guidance team was judged to fulfill the eligibility to build. Because, the design of the dam body uses dredging land with an upright core, which is based on abundant soil material sources around the site for dam body heap. The feasibility analysis of the building is acknowledged to have a benefit-cost ratio of 1.9 for 20 years, so it indicates that the dam is compatible to be built in the future.

Even because of this innovation, the design by Tirta Gangga team managed to achieve 2nd place, best maket and the best mockup in the National Dam Design Competition 2019 held at the University of Mataram, a few weeks ago.(vio/rev/ITS Public Relations)