Tire tractive performance, soil behavior under the traffic, and multi-pass effect are among the key topics in the research of vehicle off-road dynamics. As an extension of the study (He et al., 2019a), this paper documents the testing of a tire moving on soft soil in the traction mode or towing mode, with a single pass or multiple passes, and presents the testing results mainly from the aspects of tire tractive performance parameters, soil behavior parameters, and multi-pass effect on these parameters. The influence of tire inflation pressure, initial soil compaction, tire normal load, or the number of passes on the test data has been analyzed; for some of the tests, the analysis was completed statistically. A multi-pass effect phenomenon, different from any phenomenon recorded in the available existing literature, was discovered and related to the ripple formation and soil failure. The research results of this paper can be considered groundwork for tire off-road dynamics and the development of traction controllers for vehicles on soft soil.

轮胎牵引性能，交通情况下的土壤行为以及多次通过效应是车辆越野动力学研究中的关键主题。作为研究的扩展（He et al。，2019a），本文记录了轮胎在牵引模式或牵引模式下在软土上以单程或多程通过的测试，并且给出的测试结果主要来自轮胎牵引性能参数，土壤行为参数以及对这些参数的多次通过影响。分析了轮胎充气压力，初始土壤压实度，轮胎法向载荷或通过次数对测试数据的影响；对于某些测试，分析已在统计上完成。多通效应现象，不同于现有文献中记录的任何现象，被发现并与波纹形成和土壤破坏有关。本文的研究成果可以被认为是轮胎越野动力学的基础，也可以看作是在软土上车辆牵引控制器的发展。