Seismic Design Criteria for the Maleo Producer, Madura Straits

摘要

The Maleo Producer is located in the Santos' Maleo Field in the Madura Straits, Indonesia. The site is located near the southeastern tip of the Madura Island, north of Java in an area of active tectonics. The driving mechanism for earthquakes in this region is the Sunda Arc subduction zone, a 5,600 km long zone of seismic activity that defines the tectonic boundary between the Indian Ocean part of the Australian tectonic plate and the continental crust of the Eurasian tectonic plate. The Maleo Field is underlain by very soft normally consolidated highly plastic lightweight marine clay requiring a detailed site response analysis that included modeling of soil structure interaction. This paper discusses the development of seismic design criteria for the project and the input parameters for analyses of successively increasing complexity for the evaluation of the platform. The seismic design criteria included development of site-specific seabed response spectra for different return periods for an initial set of response spectrum analysis followed by the development of acceleration time histories for use in the detailed non-linear soil-structure interaction model. The paper also discusses practical considerations in the development of time histories to facilitate reasonable runtime for the global soil-structure interaction analyses.