<p>To investigate the influence of joint on blasting stress wave propagation and fracture extension, characteristics of acceleration and strain on both sides of the joint, as well as corresponding transmission coefficients, were analyzed based on single-hole and double-hole blasting experiments on granite containing a prefabricated joint. The characteristics of cracking and fragmentation distribution with different joint thicknesses and hole-to-joint distances were investigated. Using the finite element software LS-DYNA and employing the RHT model, an in-depth analysis was conducted on the propagation of stress waves and the fracture extension within jointed rock masses under blasting loads. The results show that with the increase of the hole-to-joint distance, the failure mode on the face-blasting side shifts from a rectangular to a triangular distribution. For the double-hole experiment, when the joint is close to a hole, the failure range between the joint and the hole adjacent to the joint shows a fan-shaped or rectangular distribution. The hole far from the joint generates a primary fracture perpendicular to the joint. When the joint is located at the center of the line between two holes, the failure range shows a symmetrical rhombic distribution. A primary fracture through the rock sample happens along the direction of the line between two holes. With the increase of the joint thickness, the rhombic failure range gradually decreases, which worsens the fracture formation effect along the direction of the line between two holes. Simulation results show that as joint thickness increases with a constant hole-joint distance, the reflected stress wave effect and damage range at the face-blasting side both expand. The results can provide insights into the design and construction of blasting for jointed rock masses.</p>