Engineering rock mechanics is the discipline used to design structures built in rock. Rock mechanics itself forms part of the broader subject of geomechanics which is concerned with the mechanical responses of all geological materials, including soils. Parameters considered were, the three governing materials steel, grout, and rock with two interfaces bolt grout and grout rocks. With wide application, a solid grasp of this topic is invaluable to anyone studying or working in civil, mining, petroleum, and geological engineering.
Rock quality designation rqd after twenty years, u. Increase in the standard deviation improves the rock quality. It was resolutely aimed at giving practical information to geologists, engineering geologists and engineers. The hardening parameter has drawn poor attention in classical rock mechanics. Rqd signifies the degree of jointing or fracture in a rock mass measured in percentage, where rqd of 75% or more shows good quality hard rock and less than 50% show low quality weathered rocks. Characterization of rock masses and evaluation of their mechanical properties are important and challenging tasks in rock mechanics and rock engineering. Rock mechanics and rock engineering threedimensional 3d multiscale characterization and investigation of rock fractures 3d strength criteria for rocks evaluation of mechanical and hydraulic properties of jointed rock masses development of rock expert system res for evaluation of rock properties. Harrison book covers the basic rock mechanics principles, how to study the interactions between these principles and a discussion on the fundamentals of excavation and support and the application of these in the design of surface and underground structures. The rqd in percent is obtained by dividing the sum of all the. Since in many cases rock quality designation rqd is the only rock mass classification index available, this paper outlines the key aspects on determination of rqd and evaluates the empirical methods based. Rock quality designation rqd is a modified core recovery percentage in which the lengths of all sound rock core pieces over 100 mm in length are summed and divided by the length of the core run.
Extensively updated throughout, this new edition contains substantially expanded chapters on poroelasticity, wave propogation, and subsurface stressesfeatures entirely new chapters on rock. Rock quality designation rqd is a standard technique in the mining industry for the qualitative and quantitative assessment of rock quality and degree of jointing, fracturing, and shearing in a rock mass. Rock quality designation, rqd, was introduced by deere as a form of modified. Study of scale effects of rock quality designation rqd measurements using a discrete fracture network approach by rongzhen wang b. Subsequently, it was incorporated into the rock mass rating rmr and q system classification methods that, worldwide, now play substantial roles in rock mechanics design, whether for tunnels, foundations, rock slopes or rock excavation. Rock mass characterization is an integral part of rock engineering practice. The models as a whole cover almost all of the feasible region in the rqd versus average number of discon tinuity domain. Total recovery of drill core and length of intact pieces high recovery and long pieces indicate solid unfractured rock low recovery and crumbled pieces indicate highly fractured rock example. The rock quality designation rqd is a commonly used index for. Rock mass is a matrix consisting of rock material and rock discontinuities. Jul 15, 2019 the detailed syllabus for rock mechanics lab b. In practice, a high rqd value does not always translate to high quality rock. Widely regarded as the most authoritative and comprehensive book in its field, the fourth edition of fundamentals of rock mechanics includes new and substantially updated chapters to this highly praised text. He is the author of two books and has published more than 100.
No rqd rqd value 1 very poor 27 joints per m3 0 25 2 poor 20 27 joints per m3 25 50 3 fair 19 joints per m3 50 75 4 good 8 12 joints per m3 75 90 5. The knowledge and indication of the geotechnical characteristics including rock strength parameters is evidently. Determination of point load index strength of a given rock sample. Practical rock mechanics provides an introduction for graduate students as well as a reference guide for practicing engineering geologists and geotechnical engineers.
Since in many cases rock quality designation rqd is the only rock mass. Rock mechanics problemsrock mechanics problems how will rock react when put to mens use. Such earth materials include soil, dimension stones, slate, soilcement mixtures, ground water. Pdf rock quality designation rqd, was introduced by don deere in the mid 1960s as a means of using diamond core to classify rock for engineering. Rock mass characterization for underground hard rock mines. There are several classification systems used in underground mine design, however, most canadian mines rely on only one of three classification systems.
Geotechnical engineering standards astm international. This text can help ensure that ground models and designs are correct, realistic, and produced costeffectively. Rock mechanics is the study of geotechnical responses of geological phenomena. The models as a whole cover almost all of the feasible region in the. American society for testing and materials reprinted from the. Recent developments in geotechnical engineering for hydro projects. Use and abuse of rqd in underground mine design springerlink. The proposed models are verified with the limited amount of data that are available in the rock mechanics literature. Rock quality designation an overview sciencedirect topics. Yet, the understanding of this phenomenon is fundamental if a material is used in any engineering design, whether the aim is to prevent failure of the structure or to promote it. Rqd models and fracture spacing journal of geotechnical.
The published work that introduced rqd to an international audicnce, and that no doubt was responsible for its rapid growth in use in many countrics, was rock mechanics in engineering practice 1968 51. Fracture theories existing are generally empirical and derived from experimental results of laboratory test with simple boundary conditions. These structures encompass building foundations, dams, slopes, shafts, tunnels, caverns, hydroelectric schemes, mines, radioactive waste repositories and geothermal energy projects. Tech 20162017 r16 third year second sem is as follows.
Study of scale effects of rock quality designation rqd. Determination and applications of rock quality designation rqd. The behavior of intact rock material can be determined by continuum mechanics but rock masses are usually highly fractured. He is the author of two books and has published more than 100 technical papers.
Many rock mass classification systems use core recovery parameters as input parameter, such as rock mass rating and qsystem. Subsequently, it was incorporated into the rock mass rating rmr and qsystem classification methods that, worldwide, now play substantial roles in rock mechanics design, whether for tunnels, foundations, rock slopes or rock excavation. Journal of rock mechanics and geotechnical engineering 2016, doi. The rock quality designation rqd is a modified measure of recovery, calculated in order to estimate the quality of the intact rock mass. Rock quality designation rqd is a measure of quality of rock core taken from a borehole. Rqd helped focus the attention on the importance of rock weathering and discontinuities and on obtaining information from rock cores regarding them. This contained chapters by deere 61 and by hendron 171 in which the rqd concept and applications were discussed. Rqd is defined as the percentage of intact drill core pieces longer than 10 cm recovered during a single core run abzalov, 2016, and the general equation is expressed as. A frequently used parameter is the rock quality designation rqd index,developed by deere et al. Thanks to rock mechanics is possible to carry out stabilityanalysis, for example. The first edition of rock mechanics and engineering bridged the gap between scientific research on rock mechanics and practical engineering.
Rock quality designation rqd was introduced by don deere in the mid1960s as a means of using diamond core to classify rock for engineering purposes. These are rqd, joint set number jn, joint roughness number jr, joint alteration number ja and stress reduction factor srf. Much of the research on fracture of rocks or rocklike materials conducted over the past two decades may be considered as academic studies of the general phenomenon of fracture. Lectures on rock mechanicslectures on rock mechanics sarvesh chandrasarvesh chandra professor dt tfciilei idepartment of civil engineering indian institute of technology kanpur kanpur, 208016 india email. It is shown that a key facet of the definition of rqd is ignored in many parts of the world, and it is noted. Technical description of rock cores, rock mechanics engineering geology, 1 1622.
Pieces of core that are not hard and sound should not be included in the rqd evaluation even if they are at least 100 mm in length. Embankment dam instrumentation performance, engineering geology aspects, rock mechanics studies by kulhawy, fred h. Rock mechanics is a multidisciplinary subject combining geology, geophysics, and engineering and applying the principles of mechanics to study the engineering behavior of the rock mass. Abstract characterization of rock masses and evaluation of their mechanical properties are important and challenging tasks in rock mechanics and rock engineering. It is interesting to note that these systems, rqd, rmr and q system, have their origin in civil engineering. His research interests cover rock mechanics and rock engineering, deep foundations, geoenvironmental engineering, sustainable construction materials, and recycling and management of wastes. This system of rock mass classification is widely used in geomechanics and rock mechanics and allows to relate quality ratings to geomechanical parameters of the rock mass in excavations, foundations and tunnel support. Rqd is used as a simple classification system for the stability of rock masses. Field group subgroup classifications engineering geologyrock masses, tunnels construction park river project rock mechanics. It considers some geomechanicalclassifications, in particular. The book considers fundamental geological processes that give rise to the nature of rock masses and control their mechanical behavior. This is a pdf file of an unedited manuscript that has been. Rock quality designation rqd was introduced by don deere in the mid. Apr 30, 2007 widely regarded as the most authoritative and comprehensive book in its field, the fourth edition of fundamentals of rock mechanics includes new and substantially updated chapters to this highly praised text.
Review of previous literature and observation of test results show that hardening is highly dependent on confining pressures and the plasticity already experienced, which modify joint parameters by mutual interaction. The usefulness of rock quality designation rqd semantic scholar. Assessment of the quality of rock mass rqd rock quality designation, table 7. Tech 20162017 r16 detailed syllabus rock mechanics lab. Rock mechanics forms part of the much broader subject of geomechanics, which is concerned with the mechanical responses of all geological materials, including soils.
Goodreads helps you keep track of books you want to read. Determination and applications of rock quality designation rqd author links. This may be true based on the original definition of rqd, but is very misleading and gives the impression of competent rock. Swapan kumar haldar, in mineral exploration second edition, 2018. It involves measurement of the stability of rock strata and soil deposited within the minedout artificial voids. The rock quality designation rqd index in practice, rock classi.
What is the bearing capacity of rock on surface an at depths. Astms geotechnical engineering standards are instrumental in specifying, testing, and investigating the physicalmechanical properties and characteristic behaviors of surface and subsurface earth materials that are relevant to a construction project. This note explores the nature of rocks and rock masses as construction, foundation, or engineering materials. Rock mechanics, as applied in engineering geology, mining, petroleum, and civil engineering practice, is concerned with the application of the principles of engineering mechanics to the design of the. Estimating in situ deformation of rock masses using a. Rqd was intended as more than an index of fracture spacing.
Many variations and it s impossible to know them all for any rock mass. What happened to the mechanics in rock mechanics and the geology in engineering geology. It measures the percentage of good rock within a borehole. Rock mechanics and tunnel support pells consulting. Determination of protodyaknov index of a given rock sample. Rqd even though they possess the requisite 4 in, 100mm length. In deeres words from 1989, rqd is an index of rock quality in that problematic rock that is highly weathered, soft, fractured, sheared, and jointed is counted against the rock mass. Rock mass classification it was also felt that a system based more hil fd tl lilheavily on fundamental geological observations and less on numbers was needed hoek, 2004 a rock mass can be a very complex, highly variable material and it is unrealistic to try and quantify the individual properties that make up a rock mass. Lectures on rock mechanicslectures on rock mechanics. Rock mechanics is composed by a suite of ten softwares for rock mechanics. Practical rock mechanics teaches from first principles and aids readers understanding of the concepts of stress and stress transformation and the practical application of rock mechanics theory. The rqd was developed at a time when the field of rock mechanics was in its infancy.
Its characterization and classification aim to determine the rock mass characteristics by assigning values to a set of rock parameters. The book considers fundamental geological processes that give rise to the nature of rock masses and control their. Determination and applications of rock quality designation. Extensively updated throughout, this new edition contains substantially expanded chapters on poroelasticity, wave propogation, and subsurface. Subsequently, it was incorporated into the rock mass rating rmr and q system classification methods that, worldwide, now play substantial roles in rock mechanics design, whether for tunnels. Abstract continue on reverse if necessary and identify by block number this report discusses tunnel design procedures based on various rock mass classification systems. An ideal source for geologists and others with little background in engineering or mechanics. Physical properties of intact rocks, stresses and strains, thermal, hydraulic and mechanical. The engineering geologist is responsible for the determination of rqd. What is the response of rocks under dynamic earthquake type loading. Rock mass classification systems, that are so excellent for communications between engineers and geologists, and that can be valuable in categorizing project experience, are emasculating engineering geology and rock mechanics. Because of the basic weakness of rock intension and because in general the environmental stresses in rock mechanics are compressive most of these theories consider fracture under compressive stress conditions.
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