预应力UHPC梁弯曲性能分析与合理设计

为研究预应力超高性能混凝土(UHPC)梁的基本受力性能和合理设计方法,完成了一片大比例预应力UHPC-T形梁的弯曲全过程加载试验;基于混凝土损伤塑性(CDP)模型建立预应力UHPC梁的非线性有限元模型,对试验过程进行了细致模拟,将分析结果与试验结果进行对比;以仿真模型为基础深入研究了预应力筋数量、张拉应力、UHPC材料抗压和抗拉强度等参数对UHPC梁弯曲性能的影响规律;提出了UHPC梁的预应力配筋率计算公式,并建议了其合理范围,初步探讨了UHPC梁的合理设计方法。结果表明:基于CDP模型的有限元模型能较好模拟预应力UHPC梁的弯曲受力性能,分析结果与试验结果吻合良好;提高预应力能有效提高构件承载力,但延性降低;提高UHPC材料的抗压强度对构件弹性阶段和开裂阶段受力性能影响不大,但能有效提高构件延性,提高抗拉强度能有效提高构件的抗裂性能和延性,并使极限承载力有所提高。

Economic Feasibility Evaluation of Building Passive Houses

The research presents an improved method of rational design of energy-efficient low-rise residential buildings according to their life cycle. The mathematical model for finding the optimal version of draft power-efficient residential building has been developed. For conditions of Ukraine the optimization problem has been set and solved （finding the optimal version of the draft energy-efficient buildings）. The calculations prove the fact that the construction of passive houses in Ukraine today is economically feasible. Scientific and practical regulations, outlined in the research, can be used by all participants of the investment programs, and energy-efficiency projects, renovation projects and developing normative-technical documents.

斜管沉淀池的改造实例

文章通过实例,对飘合纸业回用水处理系统斜管沉淀池絮凝过程的絮凝池(一般常称反应池)和沉淀区进水方式进行改造;经改造后的处理效率比改造前的沉淀效率提高将近一倍;印证了絮凝池的合理设计和沉淀区的合理布水进水在斜管沉淀池中的重要地位;在实际设计中,应注意对G值的合理分配,避免在絮凝体形成之后,因水流的过度搅动而导致絮凝体的破裂。