Abstract In order to alleviate the shortage of land resources in urban areas, the double-layer compound expressway was proposed. The composition and running speed of the double-layer expressway are significantly different from that of the urban viaduct. However, due to the lack of relevant engineering practice, simulation test was carried out with the use of VISSIM platform. First, one ramp connection forms were proposed on the basis of double-layer compound expressway section: left into the right, then used the orthogonal experiment method to simulate the different traffic environment; Secondly, the test results were analyzed from the aspects of efficiency and stability, safety with Surrogate Safety Assessment Model (SSAM);Then got the comprehensive evaluation index with the entropy method, the results indicated that the ramp is suitable for situations where the main line has a small volume and a low flow direction, in addition ,it can adapt to higher design speeds. Keywords: Double-layer compound expressway ramp;Micro simulation;Traffic conflicts; Traffic efficiency; Stability of traffic flow.

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