Assessment of Bahariya Hematite-barite Ore as a Heavy Weight Concrete Mix for Subsea Pipeline Cladding

Abstract

This study deals with a substitute of high density aggregates used for offshore pipeline coating, the hematite-barite ore mined and produced by Steel Manufacture Company and not used in steel manufacture due to containing barite ore and low iron content. Heavy aggregates of iron ore were imported by petroleum companies in Egypt, for utilization as a major constituent of concrete mix used for coating of offshore petroleum pipelines as a heavy coat for pipeline stability on sea bed and mechanical protection against anchor damages. The hematite-barite heavy aggregates form the main constituents 75% of the concrete mix, with sea water cements and specific water-cement ratio desired to achieve required compressive strength, water absorption and dry density. The laboratory and field tests conducted for the hematite-barite aggregate to ensure that the physical, chemical and mechanical properties complying with coating specification and standards. The hematite-barite heavy aggregate have 3.9-4.2 g/cm³ specific gravity, well graded hematite-barite aggregate, chemically free from detrimental matter. Heavy concrete mix composed from hematite-barite aggregate, sea water cement and fresh water mixed together to produces a concrete mix of 180-185 pcf (2880-2964 kg/m³), minimum dry density and compressive strength varying from 40-47 N/mm² (400-470 kg/cm²), which satisfied the standard specification of submarine pipeline coating.