凡梁式构件,当跨度较大时,设计和施工都要求起拱。对这类构件,为什么制作时要起拱?不同的构件怎样起拱?怎样起拱才算合理?由于人们对起拱的认识不同,往往采用了不同的做法。为了保证构件起拱的合理高度,充分发挥它的结构性能,有必 Where the beam members are large in span, design and construction require arching. For such components, why do they have to be arched when they are made? How do the different components arch and how can they be considered reasonable? Because people have different understandings about arching, different approaches are often used. In order to ensure the reasonable height of the component arching and give full play to its structural performance, there must be