Experimental study of groutability of Super-Micro cement
Based on the similarity theory and the theory of model test, we simulate different opening rock fractures indoors. On account of Super-Micro cement with four different water cement ratios of 0.8, 1.0, 1.5, 2.0 under different water reducer and additive, the experiment is testing the passing rate of Super-Micro cement through the filter with diameters of 0.02mm, 0.05mm, 0.07mm. The test results indicate that the ultimate limit viscosities are 17.1mPa.s, 33.6mPa.s and 624.7mPa.s respectively when the superfine cement passes these three filtrations. After analyzing the influence of grout viscosity on passing rate, that is to say, the bigger the viscosity, the smaller the crack width.
Dam Foundation Grouting
\IDam Foundation Grouting\N provides its readers with background information that will help them deal more confidently and effectively with the design, supervision, and review of grouting practices. It presents a current overview and critical review of grouting practices in the U.S., while going beyond other grouting sources to discuss experiences in the international grouting arena. Avoiding heavy doses of theory, this book concentrates on the practical issues of dam foundation grouting such as: 1) Design considerations; 2) materials and mix design; 3) factors affecting grouting effectiveness; 4) equipment; 5) standard procedures; 6) supervision and inspection of grouting; 7) documentation of operations; and 8) quality assurance. Dam engineers, dam construction engineers, grouting supervisors and inspectors, field personnel of dam safety reviewing agencies, and engineering students will all benefit from this book. \IDam Foundation Grouting\N also offers an extensive list of references which will guide readers to additional sources of information on the subject.
Evaluation of buckling load and dynamic performance of steel shear wall retrofitted with strips made of shape memory alloy
One of the most imperfections of the steel shear wall is out of plane displacements that cause severe damage in both structural and non-structural elements. In this paper, the effects of shape-memory alloys on steel shear walls are investigated. First, a numerical analysis using the finite element method in ABAQUS software has been carried out according to an experimental test. The results of the numerical analysis have been verified with experimental results. Next, shape-memory alloy fibers have been added vertically and horizontally to various parts of the steel shear wall. The results show that retrofitting with the shape-memory alloy reduces the out-of-plane displacement of the steel shear wall under both cyclic and seismic loadings. Besides, the buckling load in the steel shear wall increases when it is retrofitted with the shape-memory alloy. Also, the total out-of-plane movement (accumulated absolute displacements) of the steel shear wall and non-structural damage are controlled by the characteristic of a shape-memory alloy material called “super-elastic”.