1.Chongqing Cultural Relics and Archaeology Research Institute, Chongqing 400013, P. R. China;2.Henan Provincial Institute of Cultural Relics and Archaeology, Zhengzhou 450000, P. R. China;3.Key Laboratory of Archaeological Exploration and Cultural Heritage Conservation Technology (Northwestern Polytechnical University), Ministry of Education, Xi’an 710129, P. R. China;4.School of Civil Engineering, Chongqing University, Chongqing 400045, P. R. China