DYWIDAG Ductile Connector System stabilizes Cilacap Oil Refinery against Earthquakes
Indonesia is one of the most important producers of crude oil in South- East Asia. Nevertheless, the country continues to depend on oil imports because of its high domestic demand. Consequently, the government has decided to increase its production capacity in its effort to become self sufficient in regards to oil supply.
The upgrade of the refinery near the town of Cilacap in Central Java is an important part of this plan. This project includes the construction of a new residue fluid catalytic-cracking unit that will increase the refinery’s LPG production by 62,000 barrels per day to a total of 350,000t per year.
Originally, the pipe rack system for Cilacap Oil Refinery was to be built as a steel frame structure. However, due to cost savings of approx. 20% and the shortened construction period of 10 instead of 14 months, the client decided to build the pipe rack using precast concrete elements.
As Cilacap city is located in the seismic zone 3, the owner decided to use the DYWIDAG Ductile Connector (DDC) System for achieving a ductile connection between the precast concrete beams and the precast concrete columns. The use of the DDC system improves the flexural capacity of connections between beams and columns as well as between columns and foundation in comparison to monolithic systems.
The key element of the connector is a high strength DYWIDAG Steel Bar in which the entire post-elastic behavior occurs, protecting the beam and column from any possible damage. The required inelastic response of the connection is completely provided by the remaining connector components.
The flexible and economic DDC frame system makes it possible to assemble the precast concrete elements in a short period of time. The excellent earthquake stabilization abilities of the DDC System have been successfully proven through extensive testing. In fact, the ductile connector can accommodate a story-drift of over 4% without significant loss of strength.
For the expansion of the oil refinery, DSI Korea supplied a total of 978 sets of DDC for 340 columns and 1,438 beams consisting of 5,200m³ of concrete. DSI Korea is proud to have contributed to the stability and seismic resistance of the Cilacap Oil Refinery.