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Buried pipelines in urban area are prone to corrosion defects for many years. Ensure the safety of buried corrosion pipelines is a key concern during tunnel blasting excavation. Based on the blasting engineering along Shenzhen Metro Line 12, the field test of full‐scale concrete pipeline adjacent blasting was implemented. The dynamic response of concrete pipeline induced by blasting vibration was analyzed by using the dynamic finite element numerical simulation method, and the reliability of numerical simulation was verified by the field monitoring data. On this basis, considering the corrosion defect morphology of pipeline, the distribution characteristics of peak particle velocity and peak effective stress of concrete pipeline with different corrosion depths, corrosion widths, and corrosion lengths induced by blasting vibration were discussed. The parameter analysis method was used to research the influence of corrosion morphology parameters on the dynamic response of the pipeline, and the corrosion depth of the inner‐wall of the pipeline was defined as the main control parameter of the dynamic response. According to the failure criteria of concrete materials, the safety criterion of corroded concrete pipelines with different service years subjected to blasting vibration was established. [ABSTRACT FROM AUTHOR]

In order to study the fracture ability classification of rock mass under the cracking action of supercritical CO2 phase transition, based on the classification theory of rock mass in blasting engineering, an analytic hierarchy process (AHP)-entropy weight method (EWM) and the cloud model classification method for rock mass cracking under CO2 phase transformation are proposed. In this method, rock density, rock tensile strength, rock wave impedance, and rock mass integrity coefficient are used as the factors to determine the level of rock mass fracturing, and the evaluation index system of rock mass fracturing is established. Through this evaluation method, the rock mass in a reconstruction project section of Nyingchi, Tibet, is classified and evaluated. The results present that this new classification method of rock mass fracture ability uses AHP–EWM to carry out the weight distribution of the classification index. In addition, it is combined with the cloud model for the classification division, overcoming the traditional classification method fixed with appraisal pattern flaw. Therefore, it has validity and feasibility. According to the characteristics of fracture ability, the rock masses in the area to be rebuilt on the Tibet Highway are divided into grade II, grade III, and grade IV, which provides scientific guidance for the construction of the project. [ABSTRACT FROM AUTHOR]