Twin tunnel excavations can seriously affect the integrity of buried pipelines. In this investigation, centrifuge model tests and numerical simulations were carried out to study the brittle damage of buried pipelines induced by side-by-side twin tunneling. In the numerical model, the pipelines were simulated as peridynamics (PD) shell structures, the surrounding soil was represented as a series of independent Winkler springs, and the modified Gaussian curve was incorporated as displacement-controlled boundary conditions on the springs to simulate the sequential excavation of side-by-side twin tunneling. The effectiveness of the numerical method was assessed by comparing with the centrifuge model test results. Due to the interactions of two tunnels, the fracture characteristics were more complex for twin tunneling compared with the case of single tunneling. The fracturing point induced by the second tunneling could deviate from the second tunnel centerline. The first tunneling without inducing damage can suppress the damage initiation and propagation in the pipeline under the second tunneling. A pipeline with a smaller diameter and a higher critical energy release rate in sandy soils with a lower friction angle and a shallower burial depth has a higher capacity to resist damage under twin tunneling, showing a greater initial fracture angle.