To characterize the three-dimensional evolution of creep damage in deep roadway surrounding rock, this study establishes a COMSOL-based (Multiphysics 6.3) integrated analysis framework coupling creep damage, seismic velocity response and three-dimensional imaging. The framework adopts the Norton–Bailey creep constitutive model, Weibull-distributed material heterogeneity and an elastic damage model to simulate the 210-day creep damage evolution of surrounding rock. The three-dimensional P-wave velocity field is then reconstructed via a regional correlation approach using active-source P-wave first-arrival times. The results show that with progressive damage accumulation, low-velocity zones gradually expand from the intersection of the fault and roadway roof towards both the fault zone and the surrounding roadway. From 90 d to 210 d, these anomalies develop into a large-scale regional low-velocity belt with significantly enhanced spatial connectivity. The fault weak plane exerts a controlling effect on damage localization and the formation of low-velocity zones. Numerical results demonstrate a distinct spatiotemporal correspondence between P-wave low-velocity zones and damage concentration areas. Furthermore, the predicted damage distribution agrees well with the field failure morphology of surrounding rock, verifying that the proposed method can effectively track creep damage evolution in rock masses and provide an analytical basis for dynamic stability evaluation and early warning of deep roadway surrounding rock.

To investigate the crack evolution mechanisms and early-warning precursors of excavation-induced rockbursts, unloading rockburst simulation tests were conducted on granite using a true triaxial testing machine. Analysis of tensile and shear crack development shows that tensile cracking dominates the early stage, with the proportion of tensile cracks exceeding 50% (N_tr > 50%), whereas shear failure becomes predominant near final rupture, with the proportion of shear cracks exceeding 50% (N_sr > 50%). Based on this, the tensile–shear ratio (TSR) is proposed to quantify the dynamic evolution of both crack types. In the present tests, a sustained TSR below 1 was observed during the transition from tensile- to shear-dominated failure, suggesting that it may be a potential precursor to imminent rockburst under the current experimental conditions. According to critical slowing down (CSD) theory, both the autocorrelation coefficient and variance of acoustic emission (AE) parameters increase significantly prior to failure. In contrast, TSR shows earlier identifiable changes and is therefore more suitable for early-stage warning, whereas CSD indicators provide clearer signals as the system approaches failure. Additionally, granite exhibits a rapidly fluctuating decline in the AE b-value prior to failure, and the precursor points identified by TSR and CSD consistently fall within the b-value decreasing interval before peak stress. These results suggest that integrating TSR and CSD indicators may be useful for staged AE-based rockburst monitoring and early warning in deep underground engineering.