CONSTRUCTION OF THE DUQM REFINERY SERVICE CORRIDOR TO THE LIQUID J

SEZAD plans to build a service corridor in the industrial zone of Duqm, Oman. The project aims to link Duqm refinery with a liquid jetty by allowing the Refinery to lay its pipes and connecting it to the Port. The project was awarded to Qurum Business Group LLC under the scope of Engineering, Procurement & Construction. The last 3 km stretch of the project lies close and parallel to the Duqm Road Nos. 1 and 5 project. This location is characterized by the significant presence of ‘soft clay/sabkha’ soil, which influences the construction of foundations of the proposed service corridor that consists of concrete sleepers supporting pipelines, service roads, etc. The FEED design requires the EPC contractor to replace the entire Sabkha soil with engineered fill if the depth of Sabkha is less than 4 m. For locations where Sabkha depth is more than 4 m, ground improvement techniques like stone columns shall be adopted. Nonetheless, the potential cost of doing stone columns is very high, and this prompted the EPC contractor to look for alternate viable options.

From the successful application of Basal Reinforcement technique in the neighboring project; "Duqm Roads 1 & 5", the EPC contractor was aware of the potential benefits of using geosynthetics to solve problems in similar ground conditions and subsequently approached Maccaferri Middle East (MME) propose a suitable alternate scheme of ground stabilization. After making the required studies, MME suggested a ground stabilization solution consisting of high strength ParaLink geogrids as basal reinforcements, underlaid by a layer of thick boulder layer. In the required sequence of works, pile driving activity is required to be done after completion of embankments. Since the expected static & dynamic loading during the pile driving activity were significant (up to 250 KPa), additionally three layers of Macgrid EG geogrid were provided below the zone of movement of pile rig machine. These three layers of Macgrid EG geogrids would disparate the pile driving loads into a wider area, thereby limiting the rut depth at the embankment top. MME was involved in the design, supply, and site assistance of the project.