Abstract: A high-strength confined concrete support system for an underground tunnel. The support system includes multiple confined concrete arches, bolts and cables, and a prestressed steel strand backfilling system. The confined concrete arches all support the surrounding rock of the tunnel and are sequentially arranged along the tunnel. Every two adjacent confined concrete arches are connected by a longitudinal connection structure. The support system is provided with a plurality of layers of steel bar meshes on the surrounding rock side and the tunnel side, and shotcrete layers are sprayed on the support system and the steel bar meshes. The prestressed steel strand backfilling system comprises a prestressed steel strand system and a filling material. The filling material fills the space between each confined concrete arch and the surrounding rock to equalize a load on the confined concrete arch and generate prestress.
Abstract: A high-strength confined concrete support system for an underground tunnel. The support system includes multiple confined concrete arches, bolts and cables, and a prestressed steel strand backfilling system. The confined concrete arches all support the surrounding rock of the tunnel and are sequentially arranged along the tunnel. Every two adjacent confined concrete arches are connected by a longitudinal connection structure. The support system is provided with a plurality of layers of steel bar meshes on the surrounding rock side and the tunnel side, and shotcrete layers are sprayed on the support system and the steel bar meshes. The prestressed steel strand backfilling system comprises a prestressed steel strand system and a filling material. The filling material fills the space between each confined concrete arch and the surrounding rock to equalize a load on the confined concrete arch and generate prestress.