Prevention and control of gas hazards in a tunnel under construction: a case study

2020 ◽  
Vol 79 (13) ◽  
Author(s):  
Qixiang Yan ◽  
Kai Yang ◽  
Wang Wu ◽  
Feng Wang ◽  
Fusheng He
2020 ◽  
Vol 9 (1) ◽  
pp. 224-240
Author(s):  
Indasah Indasah ◽  
Dedi Saifulah ◽  
Anita Restu Korbaffo

This research is a type of descriptive research using a qualitative approach design using a case study research design. Funding for the TB program in Pasuruan Regency was sourced from the APBD and also Health Operational Assistance sourced from the Special Allocation Fund decreased. The budget for TB prevention prevention programs is absorbed entirely But the performance of achieving the discovery targets is still not significant. Still not found the whole case, complete treatment has not been maximized, some even DO. TB control activities allocated for TB prevention and control services appear to be relatively small compared to the TB treatment budget. Based on all the challenges faced, a strategy was formulated to eliminate TB within the next 5 years by strengthening the leadership of a quality TB service program with a sustainable program across stakeholders


Author(s):  
Yu ◽  
Zhao ◽  
Fu

With the rapid expansion of impervious surfaces, urban waterlogging has become a typical “urban disease” in China, seriously hindering the sustainable development of cities. Therefore, reducing the impact of impervious surfaces on surface runoff is an effective approach to alleviate urban waterlogging. Presently, the development mode of many cities in China has shifted from an increase in urban scale to the improvement of urban quality through urban renewal, which is the current and future development path for most cities. Optimizing the design of impervious surfaces in urban renewal planning to reduce its impact on surface runoff is an important way to prevent and control urban waterlogging. The aim of this research is to construct an optimization model of impervious surface space layout under the framework of a geographic simulation technology-integrated ant colony optimization (ACO) and Soil Conservation Service curve number (SCS-CN) model (ACO-SCS) in a case study of Guangzhou in China. Urban runoff plots in the study area are divided according to the area of the urban planning unit. With the goal of minimizing the runoff coefficient, the optimal space layout of the impervious surfaces is obtained, which provides a technical method and reference for urban waterlogging prevention and control through urban renewal planning. The results reveal that the optimization of impervious surface space layout through ACO-SCS achieves a satisfactory effect with an average optimization rate of 9.52%, and a maximum optimization rate of 33.16%. The research also shows that the initial impervious surface layout is the key influencing factor in ACO-SCS. In the urban renewal planning stage, the space layout of the impervious surfaces with a high–low–high density discontinuous connection can be constructed by transforming medium-density impervious surfaces into low-density impervious surfaces to achieve the flat and long-type agglomeration of the low-density and high-density impervious surfaces, which can effectively reduce the influence of urban development on surface runoff. There is spatial heterogeneity of the optimal results in different urban runoff plots. Therefore, the policy of urban renewal planning for urban waterlogging prevention and control should be different. The optimized results of impervious surface space layout provide useful reference information for urban renewal planning.


2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Li Wan ◽  
Jiajia Shen ◽  
Changan Zhang ◽  
Zanquan Lin ◽  
Hu Zhang

Based on the background of the reconstruction project from Changqing Chenzhuang-Pingyin section of G220 east-deep line in China, a special tunnel structure and construction plan was carried out according to the construction measures of the shallow-buried small spacing tunnel passing underneath cultural relic buildings, and a comprehensive deformation control scheme of “CRD construction method single-arm excavation + surface grouting prereinforcement + advanced large pipe shed presupport” was put forward. The results of numerical simulation and on-site construction monitoring showed that the overall deformation of aqueduct foundation generally increases first, then decreases and increases again, and finally tends to be stable. The effects of surface grouting prereinforcement and advance large pipe shed presupport are obvious. The comprehensive deformation control scheme can ensure the safety of the existing construction and meet the safety prevention and control requirements.


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