Last month Bentley Systems announced the acquisition of the SACS business from Engineering Dynamics, and most people said, who? There wasn’t time then to answer the question, but today we can catch up a bit.

Engineering Dynamics, Inc. was founded in 1973 by three engineers who, as legend has it, wanted to commercialize aerospace CAE for broader use. Its Structural Analysis Computer System (SACS) became available in 1974 and gained traction with the offshore industry and is, according to EDI and Bentley, “the most widely used computer software for design and analysis of offshore structures”.

SACS consists of a number of structural analysis programs specific to many areas of offshore design, such as towing, flotation, launch and motion, among others. EDI has crafted the interfaces so that users can automate the output of data from one module into another, or rely on a greater level of user interaction and tweak as they go. The user defines the structure, adding material properties and environmental conditions; a non-linear solver calculates joint displacements and element internal forces. Post processors evaluate the performance of the structure for compliance with structural codes ; structures not satisfying the code can be redesigned. Finally, deformation plots, dimensioned drawings, bills of material and lofting data can be generated. [I haven’t seen SACS in action in a couple of years; this description is from memory, assisted by the flowchart at — apologies if I left out anything major.]

SACS is one of those products that can be termed a “de facto” standard in its niche, the design of fixed offshore platforms and is often specified as the analysis tool to be used, much as other industries may specify ABAQUS, ANSYS or NASTRAN. SACS has for years been integrated with major offshore rig design products including PDS, PDMS, and ACIS-based CAD tools.

The biggest question, of course, is why Bentley needed to add SACS to its portfolio; after all, it already markets the more generalist RAM, STAAD, ProSteel and Bentley Structural Modeler. SACS, tailored to the needs of the offshore rig designer, means that Bentley and its customers can better respond as the the global demand for oil leads to more rig projects — the need for this type of analysis will only grow. But SACS is also used in the design of another type of energy production: wind farms. SACS’ modules can also be used to create a model of a wind turbine, modeling the soil in which the foundation sits and the structure of the support tower. Analysts can assess the impact of ship strike (whale strike if that’s relevant, like in New England), the effects of transporting and positioning the turbine and fatigue over its life.

John Fowler, EDI co-founder and current Bentley consultant, said, “Our team is pleased to join Bentley and looks forward to … bringing a steady stream of innovative capabilities to the SACS product line. … [M]any SACS users would benefit from the enhanced collaboration and engineering content management that ProjectWise facilitates. In addition, Bentley’s ProSteel and ProConcrete structural detailing and fabrication software would fill the need among offshore platform design teams for automated documentation and detailing capabilities. And the integration of Bentley’s AutoPIPE stress analysis software would improve the engineering of offshore piping systems.”

Bentley’s reach will bring SACS to a broader audience and tighter integration with detailing tools will streamline the design workflow — and a design project’s profitability today is all about the workflow.