Research On Conformance Argument Method Of Safety Standard Of Rail Traffic Signaling System Based On UML

Signaling system is the key equipment to ensure the safe operation of the rail traffic system, in order to ensure the safety level of the system, safety assessment must be carried out before being put into operation. The basis of safety assessment is mainly derived from safety standards, at present safety assessment of rail traffic signaling system in China railway industry is mainly based on the European railway industry safety standard system. Due to the needs of the railway development, the safety standards in the application process exist differences on the interpretation of the safety concept, which leads to the safety assessment activities focus on collection of piles of the evidence artifacts, thereby affects the effectiveness and confidence of safety assessment of our railway signaling system.First, a set of safety standard meta model which based on the requirements and guidance for safety assessment of signaling system in international railway safety standard is proposed in the thesis, by taking references from method of conformance argument of international safety standards in the railway, aerospace and automotive fields. Second, UML and profile mechanism is used to realize safety standard modeling method. Based on this, conceptual modeling method is introduced to extract safety evidence model from railway safety standard. Finally, OCL is used to design the constraint relations between safety concepts in the safety standard model, which realizes the correlation between the safety evidence. The safety case model which verify the proposed modeling method is established in this thesis by utilizing CBTC system safety assessment in Beijing Chang Ping Line.The main innovations of the thesis are as follows:(1) A safety concept extracting method based on safety standard is proposed, and the standard concept model is established based on IEC62425.(2) The safety standard meta model design scheme is proposed in the thesis, meta model is instantiated as IEC62425 safety standard model, which using UML views and profile mechanism in RSA modeling environment.(3) The constraint relations between safety concepts in the safety standard model is described by OCL in the thesis. In order to ensure the consistency and integrity of attaining safety evidence.