Development of web-based system for safety risk early warning in urban metro construction

Abstract

At present, underground urban metro construction accidents in China are rising with the rapid growth of urbanization and infrastructure investment. Real-time safety and risk management during urban metro construction has become extremely important but is very difficult, time-consuming and unreliable due to the lack of information and experienced managers. This paper presents the development and application of a web-based system for safety risk early warning in urban metro construction. A hybrid data fusion model based on multisource information (monitoring measurements, calculated predictions, and visual inspections) is employed to imitate human experts to give safety risk assessment and early warnings automatically. In addition, it has significantly improved information collection, sharing and communication by establishing a collaborative platform instead of traditional manual management. The system has been successfully applied to several metro construction projects and has perfected the safety management performance in the cities of Wuhan, Shenyang, Zhengzhou and Kunming in China.

Introduction

China is placing high priority on construction and expansion of underground metro networks in urban areas. In its latest report, the Ministry of Housing and Urban–Rural Development in China estimated that there will be more than 30 cities with a total of 2495 km of metro lines before 2015. The investment for urban metro in China will surpass 1156 billion Yuan in the coming 5 years, which gives an impression of both the high ambition level of the Chinese government and the enormous efforts involved to implement the ambition.

However, urban metro construction projects are extremely high-risk due to unpredictable geological and hydrological conditions, complex construction equipment and methods, and third party impacts on the surrounding environment [1]. In addition, because of the short metro construction history in China, many cities don't have the technical and managerial expertise to safely develop their first metro lines. As a result, under the great pressure of project schedule and scale, accidents happened much more frequently in urban metro construction in China in recent years, which has caused unexpected casualties and economic losses.

Therefore, the safety risk of each identified failure mode in metro construction needs to be evaluated and prioritized so that appropriate corrective actions can be taken [2]. There is a growing perception that continuous monitoring of underground structure and environment provides the data necessary to facilitate safety risk identification and assessment during metro construction [3]. Moreover, measurement predictions calculated by mathematical and mechanical models [4], [5], [6], together with the visual inspections on construction sites by human beings have become an inherent part of safety risk analyses [7].

However, it will not be easy for Chinese engineers to manually and globally evaluate safety risk based on multisource information which may include monitoring measurements, calculated predictions, and visual inspections. To achieve that, it would require highly professional knowledge and experience, and would be extremely time-consuming and less reliable in practice due to the inherent difficulties in handling and communicating multisource information. Many attempts have been made to develop and implement safety risk management systems in urban metro construction in China using emerging information communication technology (ICT). In most cases, the solutions have been limited to measurement databases or video monitoring systems. Therefore, to improve safety performance in metro construction, efficient management of multisource information and its automated fusion into the safety risk early warnings is required, along with notification of proper countermeasures.

A successful alternative is a web-based safety risk automated early warning system which is also a multisource information management system. By using a data fusion model, a collaborative decision-making platform for work flows and responsibility allocations is also achieved. This paper introduces and discusses the experience of developing a web-based early warning system for safety risk in urban metro construction. Section 2 presents a literature review of techniques in this study, such as safety risk assessment, data fusion and web-based information communication. Section 3 then offers the hybrid data fusion model for safety risk early warning in metro construction. Next, Section 4 illustrates the system design and development. Section 5 is a case study of the system in Wuhan metro construction. Finally, Section 6 presents conclusions and further research opportunities.