Abstract : the relations between prestressed reinforcements in two directions and the total balance loading of unbonded prestressed dual concrete slabs are established in the present paper based on the analysis of projects , in which the structural cost is optimized satisfying the requirements of the service state , the ultimate state and constructions 文摘:本文在对无粘结预应力双向板两个方向平衡荷载分配方案分析的基础上，建立了以两个方向预应力筋面积与总平衡荷载的关系式，在满足极限状态、正常使用极限状态和构造要求的条件下，使结构的造价达到最佳。
Reviewing and summarizing the existence theory for maintenance time decision , their shortcomings are analyzed , in which the economic factor is considered more than the safety factor . so in this paper from the point of security and risk cost the natural usage limit state reliability index is put forward as the maintenance time decision rule . the right bank section of danjiangkou dam of the south - north water transfer project ( snwtp ) as an example is analyzed to decision the maintenance time 另外，回顾现有结构维护时间决策的准则问题，一般是偏向于从工程经济角度考虑问题，而对结构使用的安全性考虑的较少，针对上述决策准则的不足之处，本文从工程力学的角度出发，综合考虑了结构的安全性和风险，提出了以正常使用极限状态的可靠指标作为维护时间的决策准则，并以南水北调工程丹江口水利枢纽的右联混凝土坝为例进行了维护时间的决策分析。
The relations between prestressed reinforcements in two directions and the total balance loading of unbonded prestressed dual concrete slabs are established in the present paper based on the analysis of projects , in which the structural cost is optimized satisfying the requirements of the service state , the ultimate state and constructions 本文在对无粘结预应力双向板两个方向平衡荷载分配方案分析的基础上，建立了以两个方向预应力筋面积与总平衡荷载的关系式，在满足极限状态、正常使用极限状态和构造要求的条件下，使结构的造价达到最佳。
Secondly , through the examination and observation of the structural model of the cast - in - place pre - stressed compound floor slab system , under the normal usage load , the normal usage limit - state and the failing load , we have validated the space working - feature of the structural model under variable loads , including the rigidity , the crack , failing - state , failing load and the stress variation of the pre - stressed bar , and so on 其次，通过对该体系的结构模型在正常使用荷载、正常使用极限状态和破坏状态下的试验研究，验证了现浇预应力复合楼盖体系模型结构在各种荷载作用下的空间工作性能，包括刚度、裂缝、破坏形态、极限承载力及预应力筋的应力变化状态等。
The strength ductility and crack property of the high effective pre - stressed rein - forced concrete hollow slab with the medium strength spiral - continuous - ribs steel bar can meet the need of the current codes and specification by calculating the normal limit state and ultimate limit state of the pre - stressed reinforced concrete slab with middle strength spiral ribs steel wires 通过对以中强螺旋肋钢丝为受力筋的预应力空心板的承载力极限状态及正常使用极限状态的计算，证明以中强螺旋肋钢丝为受力筋的预应力空心板，其强度、延性及裂缝性能均符合现行规范规程的要求。
Equation was deduced on normal use ultimate state for cshbb based on displacement control method , whose statistical parameters of load item were got from field tests and statistical parameters of resist item were got from indoor experiments . reliability analysis was also done based on the equation 根据由现场实测得到的温差统计模式及由室内试验得到的抗力统计模式，采用有限元计算得到的近似层间相对位移计算表达式，建立了基于位移控制的小砌块建筑的正常使用极限状态方程，并对其进行了可靠度分析。
The data used by calculation program and post - processing are formed by dialog boxes , and fed back by figure . a finite element program which considers the influence of axial deformation can analyze the prestressed concrete frame structure , then the structure is designed according to the code of concrete structure gbj10 - 89 . post - processing can give the result of calulation by text file and graph , and plot construction drawings in autocad 前处理模块通过对话框采集数据来建模，并利用图形反馈建模结果；计算核心利用考虑了轴向变形的杆系有限元程序计算荷载效应和预应力效应，并按《混凝土结构设计规范》 gbj10 ? 89计算承载能力极限状态和正常使用极限状态；后处理模块通过文本文件和图形显示来完成结果查询，并直接在autocad环境下生成施工图。
