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81.
软岩巷道是巷道支护的难题之一。据具体的工程实例,分析认为巷道变形严重的主要影响因素是围岩岩性、支护整体结构和自身承载能力。基于原支护存在的问题,提出了"U型钢可缩性支架+锚网喷"的互补支护技术方案。实验结果表明,该技术取得了良好的治理效果,巷道围岩变形量明显降低,保证了巷道的正常运行。 相似文献
82.
大社矿西翼皮带年久失修巷道压力大、断层多、岩石松软,底鼓现象严重,针对这一现象,采用一种新型加固支护锚网喷、套U钢、打锚索、注水泥浆的联合支护方式,为该矿在克服复杂地质构造提供了新的支护方式,并取得了良好的社会及经济效益。 相似文献
83.
运用微波消解样品预处理技术,对训练集光谱测试数据进行小波压缩,然后用最小二乘支持向量机建立数学模型,并用检验集光谱数据考察模型的优劣,表明小波压缩—支持向量机建立的数学模型泛化能力好。试验表明,用建立的方法,测定重油中的铁、镍和钒,使测试时间由2 d缩短为5 h,与原子吸收的测试结果一致。 相似文献
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85.
Multi-model approach can significantly improve the prediction performance of soft sensors in the proc- ess with multiple operational conditions. However, traditional clustering algorithms may result in overlapping phe- nomenon in subclasses, so that edge classes and outliers cannot be effectively dealt with and the modeling result is not satisfactory. In order to solve these problems, a new feature extraction method based on weighted kernel Fisher criterion is presented to improve the clustering accuracy, in which feature mapping is adopted to bring the edge classes and outliers closer to other normal subclasses. Furthermore, the classified data are used to develop a multiple model based on support vector machine. The proposed method is applied to a bisphenol A production process for prediction of the quality index. The simulation results demonstrate its ability in improving the data classification and the prediction performance of the soft sensor. 相似文献
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88.
On the load bearing behavior of the self‐regulating interactive membrane foundation system The paper reports on a new foundation system, the self‐regulating membrane foundation, for embankments on deep soft soil deposits, such as stockpiles or infrastructure embankments. The load bearing behavior of the system was analyzed by means of centrifuge model tests and comprehensive numerical simulations, such as global sensitivity analyses and parametric studies. The results of those analyses and the derived design approach are presented in the paper. The paper concludes with a validation of the design approach, by comparison with results of the numerical simulation. 相似文献
89.
Deep mixing columns are commonly employed for soft ground improvement. However, the diameter of a single conventional column is a constant and the area replacement ratio does not vary with depth. Hence, the conventional column is not the ideal solution for multi-layered soft grounds, where different layers have remarkably different soil properties. Accordingly, this study proposes a better solution, which is the variable-diameter deep mixing column with a large diameter in the soil layer having high compressibility and a small diameter in the soil layer having relatively low compressibility. In this study, small-scale laboratory model tests were firstly employed to compare the performance of two-layered soft grounds improved by a variable-diameter column and a conventional column. The additional vertical stress in the soil and the column, the excess pore water pressure, and the ground settlement were analyzed. Then, a field application of variable-diameter columns for multi-layered soft ground improvement was presented; the design considerations, column installation, and monitored settlement were introduced and analyzed. The results indicated that the additional stress in the soil and the column in the highly compressible soil layer were much lower in the variable-diameter column-improved ground than in the conventional column-improved ground. Consequently, the variable-diameter column-improved ground yielded less total settlement and less post-construction settlement compared to the conventional column-improved ground. 相似文献
90.