Library contains journals, books, magazines, proceedings, standards and more. Use the search to find information on tailings and related topics. Link brings you to a search of the ASCE library on "Tailings".
This bulletin was prepared to show the current state-of-the-practice for the design of new dams to resist earthquake forces and for treating existing dams to make them better able to withstand earthquake shaking. This bulletin gives remedial measures for improving the safety of existing impoundments. It also gives a very comprehensive collection of references so that the reader can go back to original sources and study various methods in greater detail.
The forecast of seismic hazard in mines depends on the planned mining sequence and therefore it is required to: 1. Model the changes in stresses and strains associated with future mining. 2. Transform these changes to the parameters of expected potentially damaging seismic events (location, time, size, mechanism). This modelling of expected seismicity has to be calibrated. It needs to be shown that the recorded seismic response to the mining in the past can be replicated using a numerical model. The seismic hazard calculated for future mining steps also needs to be tested against the observed seismicity after the planned mining is completed. The same mathematical framework can be used for both the calibration and the testing of seismic hazard forecasts. The area skill score (Zechar & Jordan 2008) is adopted to assess the match between the location of significant seismic events and calculated hazard maps for the past mining steps (calibration) and forecast maps for the future mining steps (testing). The 3D rotation angle (Kagan 2007) is used to compare the source mechanisms of recorded significant seismic events with the expected mechanisms for the past and future mining steps. The seismic events affecting the poor performance of the forecast both in terms of location and source mechanisms can guide possible adjustment to the input parameters of the model (e.g. orientation of in situ stress, failure criteria) and help to improve the forecasts. The suggested approach of calibrating and testing of seismic hazard forecasts is illustrated using data from Renison mine, Australia.
The majority of seismic hazard assessment tools are solely based on statistical analyses of several seismic source parameters such as event rate and time, and seismic moment. These analyses are often applied to the entire mining area which can impact the accuracy and reliability of the hazard assessment tool in each zone. Experience has shown that mining geomechanical risk is complex and its mitigation needs a broad understanding of other geotechnical factors such as rock mass properties, geological structures, mining method, stress regime, etc. Since all the contributing parameters and their impact are not entirely understood, it is critical to apply a range of geotechnical/geomechanical analyses in correlation to each other and quantify the changes in the rock mass behaviour. The goal of this paper is to develop a seismic hazard assessment tool calibrated for each geotechnical domain within the mine. To develop the tool, we incorporated mine geotechnical and geological data, seismic source parameters, and tomography analyses from a hard rock underground mine in North America. There exist several sub-vertical faults and one horizontal structure in the mine which create clear contrasts in rock mass behaviour across the structure. The results show good correlation among the different datasets, and a calibrated seismic hazard tool has been developed that provides ongoing updates to the mine operation.
This webinar will continue from the Introduction to CPT and take a more in-depth look at using the CPT to evaluate soils for liquefaction. It is part one of a three part series on using the CPT for liquefaction. This will cover mostly the introduction and theory.
This webinar continues on from CPT for Soil Liquefaction, part 1 and discusses using the CPT to evaluate flow liquefaction.
Dr. Robertson's technical papers on Cone Penetration Testing (CPT) and liquefaction
For structures under the jurisdiction of the USBR, the design standards present clear and concise technical requirements and processes to enable design professionals to prepare design documents and reports necessary to manage, develop, and protect water and related resources in an environmentally and economically sound manner in the interest of the American public.
These guidelines provide the basic framework for the earthquake design and evaluation of dams. The general philosophy and principles for each part of the framework are described in suffcient detail to achieve a reasonable degree of uniform application among the federal agencies involved in the planning, design, construction, operation, maintenance, and regulation of dams. The guidelines are presented in four parts: selection of design or safety evaluation for earthquakes; characterization of ground motions; seismic analyses of the dams and foundations; and evaluation of structural adequacy for earthquake loading.
Based on the analysis method for tailings dam in upstream raising method presently used in metallurgy and nonferrous metals tailings depository in the world, an effective stress analysis method of seismic response for high tailings dam was developed according to the results of engineering geological exploration, static and dynamic test and stability analysis on Baizhishan tailing dam 113.5 m high. The law of generation, diffusion and dissipation of seismic pore water pressure during and after earthquake was investigated, and the results of tailings dam's acceleration, seismic dynamic stress and pore water pressure were obtained. The results show that the seismic stability and liquefaction resistance of high tailings dam are strengthened remarkably, and the scope and depth of liquefaction area at the top of dam are reduced greatly. The interior stress is compressive stress, the stress level of every element is less than 1.0 and the safety coefficient of every element is greater than 1.0. The safety coefficient against liquefaction of every element of tailing dam is greater than 1.5 according to the effective stress analysis of seismic response by finite element method. The calculated results prove that liquefaction is the main reason of seismic failure of high tailing dams, and the effect of seismic inertia forces on high tailing dams' stability during earthquake is secondary reason. Central South University Press, Sole distributor outside Mainland China: Springer 2007.