铁路标准活载是设计铁路桥涵及线路上部建筑的主要依据。它的政策性强,牵涉面广,不仅与机车、车辆的现状和发展有关,而且与整个铁路运输的发展,以及铁路建筑物的修建标准等有关。建国前,我国铁路大部为外国投资修建;即使是自己修建,机车、车辆、钢轨、钢梁等也多为进口,类型繁杂、零乱。当时虽然也有一个“中华活载标准”,即“C—活载”,但 Railway standard live load is the main basis for the design of railway bridges and culverts and the upper part of the line. Its policy-oriented and wide-ranging aspects are not only related to the status quo and development of locomotives and vehicles but also to the development of the entire railway transport industry and the standards for the construction of railway structures. Before the founding of New China, most of China’s railway construction for foreign investment; even built their own, locomotives, vehicles, rails, steel beams, etc. are mostly imported, the type of complex, messy. At that time, although there was also a “Chinese live load standard”, that is, “C-live load”,