Description

GSB 65 GRANULAR SUB-BASE

GSB 65 (Granular Sub Base Grade 65) is a well-graded granular material used as a foundational layer in road construction, typically placed directly beneath the base course or bituminous layers. The “65” refers to the maximum particle size in millimeters, indicating that the material contains a mix of crushed stone, gravel, sand, and fines with particles up to 65 mm in diameter. GSB 65 is designed to provide structural stability, load distribution, and drainage for the pavement system. It plays a critical role in reducing stress on the subgrade and improving the overall lifespan of the road. The material is required to meet specific gradation and compaction standards as per MoRTH (Ministry of Road Transport and Highways) or relevant local specifications, ensuring minimal voids and high bearing capacity. GSB 65 must be free from organic matter, clay lumps, or deleterious materials. It is compacted using vibratory rollers to achieve desired density and strength. Due to its excellent drainage and load-bearing characteristics, GSB 65 is widely used in highways, rural roads, airport runways, and industrial pavements as a cost-effective and durable sub-base solution