Urban water security problems such as water scarcity, water pollution, and flood disasters have restricted the sustainable development of cities. In order to scientifically evaluate the urban water security situation, this study combined the DPSIR (driver, pressure, state, impact, response) model and HEVD (the hazard of disaster-causing factors, the vulnerability of disaster-affected bodies, the instability of the disaster-pregnant environment, and population loss) model to propose a new conceptual framework for DPEBLR (driver, pressure, environment, insecurity-affected body, loss, response). Based on this conceptual framework, 35 indicators were selected to establish an urban water security evaluation index system. In order to solve the problem of randomness and fuzziness of the boundary values of urban water security classification levels, the cloud matter element model was applied. Chongqing was used as an example for verification, and the results showed that the water security status of Chongqing City improved from 2011 (Ⅴ) to 2019 (Ⅱ). This indicates that the water ecology restoration project, centralized water source protection project, centralized water supply project, water-saving society transformation, and flood and drought prevention system construction project implemented in Chongqing has achieved significant results. However, Chongqing still faces the problem that the construction of an urban flood control system cannot meet the speed of urban development. The government should slow down the urbanization and allow the urban flood control system to be ready before the area is occupied. In addition, the awareness of water conservation for industrial use in Chongqing has been formed, and citizens’ awareness of water conservation for domestic use should be enhanced in the future.

Deep underground excavation subjects hard rock to complex confinement-release histories, yet how continuous versus stepwise unloading reorganizes progressive damage remains poorly understood. Here, 30 hard-limestone specimens were tested under uniaxial compression, conventional triaxial compression, continuous confining-pressure unloading, and stepwise unloading at initial confinements of 10, 20, and 30 MPa, with synchronous acoustic-emission (AE) monitoring. Mechanical deformation was evaluated together with AE energy, frequency, RA–AF characteristics, upper-tail amplitude, phase- and cycle-resolved energy partitioning, and failure-proximal activity. Although continuous and stepwise unloading entered the unloading stage from comparable stress states, they produced distinct deformation and energy-release histories. Continuous unloading showed stronger terminal AE-energy localization and greater specimen-to-specimen variability, particularly at low confinement, whereas stepwise unloading distributed AE energy more progressively throughout repeated pressure-drop and hold phases. AE activity persisted during the hold periods, indicating continued internal damage evolution even when the externally imposed confinement was temporarily unchanged. By contrast, the central peak-frequency range, RA–AF characteristics, and upper-tail amplitude varied only modestly between unloading paths, suggesting that unloading mode primarily reorganized the timing and concentration of damage-related energy rather than fundamentally changing the dominant AE signal population. Failure-proximal high-energy activity was also more temporally concentrated under continuous unloading, while stepwise unloading produced a more distributed accumulation history before instability. These results demonstrate that the temporal mode of confinement release is a key control on damage accumulation, energy localization, and the approach to instability in hard limestone, providing a mechanistic basis for interpreting path-dependent failure in deep underground excavation.