羊城铁路总公司实现二代机联网后的新举措张占海京广线衡广段复线自１９８８年底开通以来，客货运量猛增，列车密度日益加大，尤其是为保障处于郴州以南乐昌以北两大隧道（南岭隧道长６．７ｋｍ，大瑶山隧道长１４．２９５ｋｍ）及一些区段隧道群（如菠罗坑至旧横石间）的... Yangcheng Railway Corporation to achieve the second generation of new measures after the Internet Zhanghanhai Beijing-Guangzhou line Hengguang Duanquansu since the end of 1988 opened since the surge in passenger and cargo traffic, increasing train density, especially in order to protect the south of Chenzhou in Lechang to North two tunnels (Nanling tunnel 6.7km long, Dayaoshan tunnel 14.295km long) and some sections of the tunnel group (such as the spinach pit to the old cross-stone room) ...