The quality of fit of the regression model, moreover, was assessed by the correlation and determination coefficients. The correlation coefficient ( R ) measures the strength of the linear correlation between the dependent and independent variables in the regression model, whereas the coefficient of determination ( R 2 ) indicates the percent of variance in the dependent variable, which can be explained by the independent variables of the model. The higher the coefficients of correlation and determination the better the quality of fit. The algebraic sign of the regression coefficient, on the other hand, denotes the direction of the corresponding buildability factor’s effect on labor productivity, i.e., positive or negative.
Discussion of Results and Practical Implementations of Findings
The effects and relative influence of primary buildability factors on concreting labor productivity are determined and quantified. Few published quantitative results exist with which to compare the findings of this investigation, however, available data have been examined and discussed.
For both placement methods investigated, a significant gain in concreting labor productivity is associated with high slump mix. High concrete workability has the advantages of permitting easy and quick placement (Ramachandran 1979). More energy and additional input, moreover, are needed for compacting and consolidating the fresh concrete as the workability of the mix decreases. On average, a loss of 23% in labor productivity is determined as a result of pumping medium, in comparison with high concrete workability. A consistent pattern in labor productivity loss is depicted in skipped concreting between high and medium workability mix. Nevertheless, because of the difference in the placement mechanisms between the two methods, i.e., skipped and pumped, the quantified difference in productivity loss between placing medium, compared to high concrete workability, is higher, on average, by 30%.
Furthermore, the average percentage gain in labor productivity as a result of placing medium, in comparison with low concrete workability, is 59% for pumped versus 58% for skipped concrete. An average percentage increase of 108 and 125% in labor productivity, in addition, is associated with pumped and skipped high, in comparison with low concrete workability, respectively.
影响混凝土浇筑劳动生产率的可建造性因素摘要
因为钢筋混凝土这种材料对行业的重要性,提高现浇钢筋混凝土建筑的劳动生产率是必要的。好几个因素影响劳动生产率,但可建性是其中最重要的。尽管这些年来有很多关于结构生产率的报道,对一份文献的彻底检阅揭示了缺乏对可建性因素的有效研究对混凝土浇筑效率的影响。因为混凝土浇筑是一个完整的,劳动密集,在原地进行的钢筋混凝土结构,这次研究的目的是探索主要可建造性因素对混凝土劳动生产率的影响。为达到这一目标,用分类回归的方法收集和分析了大量生产率数据因此,效果和相对影响:(1)混凝土和易性;(2)钢筋拥堵;(3)体积盆满;(4)高度相对于地面水平,劳动生产率跳过,泵的放置方法确定和量化。调查显示显著的因素影响着素混凝土浇筑的效率,可为设计人员提供反馈了解他们的设计考虑了可建性需要的概念,以及操作者生产率的有形的结果。此外,提出切实可行的建议,可能会提高这个行业的可建造水平,从而转化为更高的劳动生产率,降低劳动成本。另一方面,模式结果的描述可以提供指导施工管理进行有效的规划和高效的劳动力和设备利用率。 现浇钢筋混凝土建筑生产率英文文献和翻译(5):http://www.youerw.com/fanyi/lunwen_3299.html