Gasoducto Sur Peruano

GEOTECHNICAL LAYOUT AND DESIGN

FEED Engineering - South Peruvian Gas Pipeline – Peru

 

Challenge:

Define, together with our Client, the final route in the FEED (Front End Engineering and Design) engineering phase of the 1060 km-long Trunk Line and branches of the South Peruvian Gas Pipeline (GSP). The project covers three geographical regions in Peru (the jungle, the mountain ranges, and the coast), with elevations ranging from sea level to 4,920 meters above sea level and with more than 50% of the route at a height above 4,000 m.a.s.l. To join the start and end-points, the trunk line of the GSP must traverse areas with varied and complex lithologies and geological formations, some of them heavily affected by tectonics and others by volcanism.

Solution:

To meet this challenge, a team was formed with professionals from both the Client and Antea®Group (50-50). The work began in-office, with the review and preliminary sketch of the pipeline route from aerial photographs and satellite images as well as from information gathered by helicopter overflights. Then, prior preparation for the works in the jungle and physical conditioning for the works in the mountains at heights above 4,000 m.a.s.l., field trips were undertaken by eight committees to design the layout; each committee was led by an expert in layout and geotechnical design and consisted of more than 20 members, including professionals in engineering, geology, biology, archeology, social, HSE as well as the guides.

Along with the fieldwork, the LIDAR (light detection and ranging) information was collected, from which the images and digital terrain models were obtained. With the collected field information, we then proceeded to refine the layout on the images and the LIDAR topography, and obtained the final version of same in order to then proceed with the geotechnical and mechanical designs of the gas pipeline.

Outcome:

The adjustments made to the layout involved performing long variants to the initial alignment in more than 40% of the route. We finally succeeded in establishing the best route for the GSP, with zero accidents and with a minimal increase in length vs the preliminary layout.