针对目前我国跨度最大的球面网壳工程，漳州后石电厂123m直径双层球面网壳，所采用的一种新的施工方法——小拼单元悬挑安装法施工技术进行了全面介绍，同时对结构在施工过程中杆件的内力变化进行了全过程的跟踪计算分析。分析结果表明，这种方便、廉价的施工新方法在技术上是可行的，结构在施工中是安全的工程实践证明，这种用简易的施工机具安装大型网壳的施工方法是成功的并特别指出网壳工程设计时考虑施工过程的重要性，同时对确定网壳施工方案时应注意的一些问题提出了建议。

本文引入初内力的概念，提出并建立初内力准则方程式来简化分析计算预应力网架结构。这种简捷计算法在分析各种预应力工况时，只要一次性建立、分解和应用网架的总刚度矩阵，使计算工作量大为简化。当单根杆件施加预应力、多根杆件施加预应力、同一杆件各股分别施加预应力以及分级分批施加预应力时，采用本文提出的方法可方便求得各工况下预加应力全过程的网架内力和变位及其变化规律，并可一次性地完成预应力施加工作。文中附有多个算例，计算结果表明，本文提出的简捷计算法是正确、可靠和有效的。

The last decades have seen major advances in the research. Design and construction of steel (pace structures space grid structures) in China. This paper provides a review of these developments. With partieular attcntion to the new technologies and new structural forms employed in China. The fllowing topics on new technologyies and new structures are given emphasis; long-span and large-arca grid structures. Composite space trusses; composite reticulated shells; triple-layer space trusses; partial double-layer (single-layer) lattice shells: prestressed grid structures. Cable-stayed grid structures: special trid structures: new types of joints; theoretical work and application research. Prospects for steel space structures in thd 21st century are presentel at thd end of this paper.

Pretensioned long span steel space structures are a new type of hybrid structures resulting from combining modem prestressing technology with long-span structures such as space grid structures (including space trusses aod lattice shells), cable-bar tensioned structures and spatial truss structures. These structures have been developed rapidly and have round many applications in China in the recent decade This paper provides a review of applications and developments of pretensioned long span steel structures in China The following topics on new technologies and new structures are given emphasis prestressed grid structures, cable stayed grid structures, beam string structures and prestressed segmental steel trusses. Prospects for pretensioned steel space structures are presented at Ihe end of the paper.

本文彩用矩阵位移法，引入初内力的概念，提出并建立了初内力准则方程式，再运用线性叠加原理来简化分析计算杆件去除与内力变更时的空间网架结构。这种简捷计算法在所讨论的工况下只要一次性的建立、分解和应用网架结构的总刚度矩阵，无须重复多次建立和分解总刚度矩阵，从而使计算工作量成倍地甚至几十倍地大幅度减少。特别是当网架结构多根杆件同时断杆、依次先后断杆、预应力及分期分批施加预应力时，采用本文方法可更方便地求得各工况全过程的网架内力、变位及其变化规律。文中附有多个算例，计算结果表明本文提出的简捷计算法是正确、可靠和有效的。