发展低碳冷拔丝先张法预应力混凝土构件至今已有20年左右时间。早期生产的预应力混凝土构件多数是非标准化、定型化、小批量生产。全部采用木模。为方便固定木模,普通混凝土台柱的台面建造的时候,横向方向每隔1～1.5m距离预埋木条。当时又对台面质量要求重要性认识不足,台面高低不平,表面粗糙,多数采用二次加浆抹面。伸缩缝间距又没有通过计算,只按构件生产布 It has been around 20 years since the development of low-carbon cold-drawing wire pretensioned prestressed concrete components. Most of the pre-stressed concrete components that were produced in the early stages were non-standardized, shaped, and produced in small batches. All use wood model. In order to facilitate the fixing of wooden molds, when the mesa of ordinary concrete pillars is constructed, the wooden strips are embedded at intervals of 1 to 1.5 m in the lateral direction. At that time, the importance of the quality requirements of the countertops was not well understood. The countertops were uneven and the surface was rough. Most of them used secondary pasteurization. The distance between the expansion joints has not been calculated, only the production of cloth by component