研究目的：平盐铁路位于深圳市龙岗、盐田区,是主要承担盐田港海铁联运集装箱运输的货运专用铁路,因既有线技术标准较低,已成为制约平盐集疏运系统能力的瓶颈,需要对平盐铁路进行扩能改造。平盐铁路沿线城市化程度高,既有线改建控制因素多,本文通过对平盐铁路的线路改建方案研究,对发达地区的既有线改建研究思路和原则进行探讨,重点研究沿既有通道地下增建二线方案和沿既有通道地下新建双线方案。
研究结论：（1）沿既有通道地下新建双线方案虽投资有所增加,但新建双线标准提高至120 km/h,可有效提高货物集散效率;（2）深圳市城镇化程度高、人口密集、城市土地开发强度极高,控制因素多,通道内工程建设环境极为复杂,新建双线方案以隧道通过城区,减少对城市的影响,集约利用土地资源,契合城市规划和项目详细规划;（3）研究推荐采用沿既有通道地下新建双线方案;（4）本研究成果应用于平盐铁路改建方案的勘测设计中,与项目可行性研究审查批复方案一致。

Research purposes: The Pinghu South-Yantian Port Railway, located in Longgang and Yantian districts of Shenzhen, primarily handles the container transportation for Yantian Port’s sea-rail intermodal operations. Due to the low technical standards of the existing line, it has become a bottleneck constraining the capacity of the Pingyan transshipment system and it's necessary to enhance the capacity of the Pinghu South-Yantian Port Railway. The urbanization level along the Pinghu South-Yantian Port Railway is high, making the reconstruction of the existing line a complex task with many controlling factors. This paper primarily studies the reconstruction plans for the Pinghu South-Yantian Port Railway, exploring the research approach and principles for reconstructing existing lines in developed areas.
Research conclusions: (1) Although the underground double-track scheme along the existing route has increased investment, the new double- track standard raised to 120 km/h can improve the efficiency of goods assembly and distribution. (2) considering the high level of urbanization, dense population, and extremely high urban land development intensity in Shenzhen, along with numerous controlling factors and extremely complex construction environment within the route, New double-track plan for underground construction along existing channels uses a tunnel through the urban area, which can reduce the impact on the city, save land resources, and align with urban planning and detailed project planning.(3)The research recommends adopting the new double- track plan along the existing route.(4) The results of this study are applied to the survey and design of the the Pinghu South-Yantian Port Railway renovation plan, which is consistent with the project feasibility study approval plan.