中文摘要：

运用生长曲线理论对中国铁路网演化（1949–2020年）的生命周期进行判定,旨在得到铁路网在时空演化中的周期性变化和生长规律.根据调整拟合优度最大隶属原则,将中国铁路网演化曲线逐步融合划分成为4个生命周期.选择四个典型的生长曲线模型,对每一个生命周期的曲线进行拟合识别,得到中国铁路网演化生命周期遵循Logistic模型的生长规律和每个生命周期的生长曲线公式及参数.研究表明,中国铁路网演变遵循连续形生长曲线特征,分别为萌芽期（1949–1969年）,发展期（1970–1988年）,调整期（1989–1998年）和繁荣期（1999–2020年后）,每一个生命周期都遵循着发生、成长到成熟的生长特征.目前中国铁路网处于第四生命周期中的成长期,周期结束时间约为2023年,里程将达到12.537万km.相关部门应当根据铁路网演化生命周期的生长规律,在不同生长阶段采取相应的发展策略,指导和促进中国铁路网顺利过渡到下一生命周期.

英文摘要：

Life cycle assessment（LCA）of China＇s railway network evolution（1949–2020）is to obtained the periodic change and development law on spatiotemporal evolution by using growth curve theory.According to the maximum membership degree principle of adjust goodness of fit, the evolution process of China＇s railway network were gradually fused four life cycle. Four typical growth curve model are adopted to fit the curves with each life cycle, then get the evolution law that the life cycle of China＇s railway network follow the laws of Logistic model and the calculation formula and parameter selection of each life cycle is introduced. The results show that China＇s railway network evolution follow the characteristics of the continuous form of growth curve and grouped into four life cycle, sprout cycle（1949–1969）,development cycle（1970–1988）,adjustment cycle（1989–1998）and prosperous cycle（1999–2020 later）, each cycle follow the growth law like generation, growth and maturation. At present, the evolution of the railway network is in the growth stage of the prosperous cycle, the end of the life cycle time is about 2023, the total length of China＇s railway network will reach 125,370 km. The related departments should take appropriate development strategy in different stages according to the growth law of China＇s railway network evolution,guide and promote the China＇s railway network transition to the next life cycle smoothly.