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.
Numerical Simulation of Thermal Sensitivity for Explosives
In order to compare the thermal sensitivity of several typical explosives, this article solved numerically one-dimensional transient heat conduction equation including thermal decomposition for explosives with finite difference method. The explicit difference equations under different boundary conditions were established, and the corresponding stability criterion was derived. The ignition times for typical explosives were calculated, which was used to evaluate thermal sensitivity of explosives.