一、从工程需要出发,立即起草一个规范初稿,用于征求意见,这是当务之急现行《铁路桥涵设计规范》,所采用的是容许应力法。此法的主要缺点,一是思路窄,所能据以提出的验算方式有局限性,使我们在针对不同极限状态制订不同对策方面,思想上受束缚;二是只使用一个笼统的安全系数,将荷载和抗力搅在一起考虑,使某些问题难于正确处理。为了适应修 First, starting from the project needs, immediately drafted a draft specification for comments, which is the top priority of the current “Code for design of railway bridges and culverts,” is used to allow the stress method. The main shortcomings of this law, first, are narrow ideas and limitations on the way in which the checking can be put forward so that we can be bound by our thinking in formulating different solutions to different extreme conditions. Second, we only use a general safety factor, Mixing loads and resistance together makes it difficult to handle certain problems correctly. In order to adapt to repair