Weike Duanmu’s scientific contributions

This study involved the construction and explosion of a large-scale (80-meter-long) underdrain and detailed investigations of the damaging impacts of a gas explosion to provide an experimental foundation for similarity modeling and infrastructural designs. The experiment vividly recreated the scene and explosion damage of the “11.22” explosion accident in Qingdao, China, thus allowing for evaluations of the movements and destruction of the cover plates. The damage mechanism was determined by analyzing the overpressure curves inside and outside the underground canal. It was determined that the cover plates were first lifted by the precursor wave, which induced a maximum overpressure of 0.06 MPa and resulted in explosion venting. The pressure entered the deflagration stage at the end of the explosion. The combustion wave overpressure reached 3.115 MPa close to the initiation point, and had a significant influence on the projectile energy of the cover plates there. Overall, 64% of the cover plates were only affected by the precursor wave, while 36% of the cover plates were subjected to both the precursor wave and the combustion wave; these cover plates were severely damaged. The results of this study provide fundamental insights relevant to the prevention and control of underdrain gas explosions.

The leaked gas from urban pipelines can easily spread to adjacent underground spaces and cause dangerous explosion accidents, therefore it is crucial to accurately identify underground spaces with high explosion consequences quantitatively, which is the key link to carry out the underground space explosion risk assessment. This paper proposes a method to quantitatively estimate the consequences of the urban underground drainage explosions. The method is established based on a large-scale underground explosion experiment and consists of several damage indicators as well as correction factors. The effects of fragments after the gas explosion, overpressure, and ground vibration post-explosion on nearby residents, infrastructures, and buried pipelines are quantitatively investigated through experimental results and theoretical analysis. The social impact and rescue force distribution affected by the explosion are assessed. A case study was generated in urban area which showed that this method is practicable. The results presented here may provide sound theoretical guidance for urban pipeline risk assessment and explosion hazard control.

Gas leakage from buried gas pipelines in urban areas can lead to accidents involving fire and explosion when the gas gets concentrated into the adjacent underground spaces. Determining monitoring points for the gas leakage in the underground spaces can prevent the initiation of fire and explosion. In this regard, this study proposes an optimized distribution model which relies on risk prediction. It maps the fire and explosion risk in the underground spaces to the discrete target pipeline based on the effect predicted by the monitoring sensors. Moreover, the total risk in this system is calculated through the micro-element method to design an effective distribution optimization strategy. A case study is conducted to illustrate the effectiveness of the new approach and compare it with the risk-based distribution method and effective monitoring length method. The results show that determining the optimized distribution plan is difficult using the risk-based distribution method and effective monitoring length method because these methods may determine a large number of monitoring points or cannot determine the specific location of the monitoring point. The proposed optimization model enables to derive the relationship between the number of distribution points and the risk in the system. For the same number of monitoring points, the rate of risk control in the system of the proposed model is twice that of the conventional model. As the number of monitoring points decreases, the monitoring cost for the prevention of fire and explosion would be largely reduced.