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41.
Calculating the elastic moduli of steel-fiber reinforced concrete using a dedicated empirical formula 总被引:1,自引:0,他引:1
The equivalent inclusion method (EIM) is adopted to study the characteristics of the equivalent material properties of steel-fiber reinforced concrete as a function of the volume fraction and the length to diameter ratio of the fibers. It is found that the equivalent material moduli of concrete reinforce with randomly orientated and distributed fibers are insensitive to the length to diameter ratio of the steel fibers. A set of empirical formulae is then proposed for the purposes of engineering applications. The proposed empirical model can simplify the calculation of the equivalent material moduli. Verifications of the proposed empirical formulae with the EIM model and with experimental data are performed with two examples. The first is a compression test. The second is 4 point bending test. The empirical formulae, based on the equivalent inclusion method proposed in this study, represent an alternative means of quickly calculating the effective elastic modulus of steel-fiber reinforced concrete materials. 相似文献
42.
Emotional support is known to provide psychosocial benefits for women with breast cancer, but women can experience a mismatch between support that is wanted and support that is received from their personal supporter. The role of wanted and unwanted support in psychosocial adjustment was examined in 79 women recovering from breast cancer. Four distinct patterns of desired support actions were found using cluster analysis. Patterns of wanted support were not related to better or worse psychosocial adjustment. However, a misalignment of support between the provider and the receiver significantly influenced psychosocial adjustment, and unwanted but received support (support commission) was uniquely associated with poor psychosocial adjustment. Clinical interventions using the support instrument could help match support providers' actions to receivers' preferences. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
Catalin Gheorghiu Pierre Labossière Alexandre Ra?che 《Canadian Metallurgical Quarterly》2004,8(3):211-218
Many countries around the world have tremendous needs to repair and strengthen their transportation infrastructure. Almost everywhere, traffic loads have reached levels largely exceeding design expectations. Northern countries also experience severe winter conditions that are combined with an extensive use of deicing salts and accelerate structural deterioration. In Canada, the extent of deterioration has prompted many authorities, including the federal and provincial governments, to investigate the potential use of fiber-reinforced polymer products to extend the life of their existing structures. However, it is widely recognized that the large-scale implementation of these products is often impaired by the lack of data on their durability. This paper presents an experimental project undertaken in order to assess the durability of reinforced concrete beams externally strengthened with two types of carbon-fiber-reinforced polymer (CFRP). The beams were first exposed to either wet-dry cycles or continuous immersion in water and then were loaded in fatigue. Finally, they were tested quasi-statically under four-point bending up to failure. The test results presented here provide some insights on the potential long-term performance of CFRP-strengthened beams exposed to severe environmental conditions. 相似文献
44.
M. Mahesh Y. S. Wong J. Y. H. Fuh H. T. Loh 《The International Journal of Advanced Manufacturing Technology》2006,31(3-4):374-387
This paper presents a methodology of using six-sigma quality tools for benchmarking of rapid prototyping & manufacturing (RP&M) processes. It involves the fabrication of a geometric benchmark part and a methodology to control and identify the best performance of the process to reduce the variablity in the fabricated parts. The approach is demonstrated with a case study based on the direct laser sintering (DLS) process for prototyping using plastic powder. In the case study an identified set of six-sigma/ statistical process control tools is employed to determine and best tune factors affecting the desired outcomes of the built parts. 相似文献
45.
在预应力双向网格井字梁屋盖施工中,对井字梁的预应力摩擦损失、锚具变形、钢筋内缩、弹性压缩和反拱及挠度进行了实测,以检验梁中建立的有效预应力能否达到设计要求,并与理论值进行比较。 相似文献
46.
李建红 《平顶山工学院学报》2010,19(5)
介绍弹塑性动力时程分析的基本原理和分析方法,并以某钢筋混凝土高层双塔连体结构为研究对象,建立大楼结构的分析模型,分别对结构进行了不同设防烈度和不同场地类别下的弹塑性动力时程分析,并进一步考虑P-Δ效应对结构的影响,对结构的抗震性能进行评估. 相似文献
47.
通过用力学方法对冶金工厂钢筋混凝土双格圆筒料仓在不同储料载荷情况下的内力分析,提出了双格圆筒料仓壁简化计算方法,给出了荷载变位计算公式. 相似文献
48.
Demarcating distribution area of goods is often guided by the rule of thumb by business proprietors.However,this method seems to be unsuitable when the demand points increase to a certain large extent.The present work attempted to convert the problem of distribution area demarcation into a localized problem of warehouseing and networking,and tried to establish district-based planning mode based on location based heuristic (LBH).Two methods were used in this study:1) the manual method to construct the mathematical model and conduct simulation;2) the automatic method using TransCAD software of geographical information system (GIS) for simulation.By comparing the effects of the two methods,the research provides theoretical support for business proprietors to demarcate the distribution area rationally with the application of GIS system.The results show that GIS has very good graphics construction function to replace complex text,and the automatic demarcating mode with human-machine interaction provides a good business decision-making support. 相似文献
49.
基于Web的谈判支持系统的研究与开发 总被引:4,自引:0,他引:4
论述了谈判支持系统的有关理论、应用现状以及存在问题,并通过对一个基于Web的谈判支持系统的分析提出了一种解决问题的新思路。 相似文献
50.