Rock mechanics problemsrock mechanics problems how will rock react when put to mens use. Use and misuse of rock mass classification systems with particular reference to the qsystem 5 2. Rock quality designation index rqd the rock quality designation index rqd was developed by deere deere et al 1967 to provide a quantitative estimate of rock mass quality from drill core logs. What is the response of rocks under dynamic earthquake type loading.
Rock quality designation rqd has several definitions. Genesis and definition of rock mass designation rqd in 1964 and 1965, whilst working on sites in granite at the nevada test site for nuclear bombs, deere and coworkers see deere 1968 and deere and deere 1989 devised an index, rqd, to differentiate between relatively good quality rock and poor rock when logging rock core, as an alternative to just judging quality on the basis of core recovery. The rock quality designation rqd is a modified measure of recovery, calculated in order to estimate the quality of the intact rock mass. It measures the percentage of good rock within a borehole. Rock quality designation rqd is a rough measure of the degree of jointing or fracture in a rock mass, measured as a percentage of the drill core in lengths of 10 cm or more. An astm designation number identifies a unique version of an astm standard.
Many variations and it s impossible to know them all for any rock mass. Rock quality designation rqd is a measure of quality of rock core taken from a borehole. Rqd is defined as the percentage of intact core pieces longer than 100 mm 4 inches in the total length of core. Rock mechanics series on rock and soil mechanics vol. These structures encompass building foundations, dams, slopes, shafts, tunnels, caverns, hydroelectric schemes, mines, radioactive waste repositories and geothermal energy projects. 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. Rock quality designation rqd rough is the measure of the degree of jointing or fractures in a rock mass, measured as a percentage of the drill core in lengths of 10 cm or more. 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.
The empirical methods based on rqd provide a convenient way for estimating the mechanical properties of rock masses but, whenever possible. Lectures on rock mechanicslectures on rock mechanics. When evaluating rock core, the engineering geologist should make note of the following. This book is a collection of isrm suggested methods for testing or measuring properties of rocks and rock masses both in the laboratory and in situ, as well as for monitoring the performance of rock engineering structures. Pdf determination and applications of rock quality. Download introduction to rock mechanics download free online book chm pdf. Rock mechanics is the theoretical and applied science of the mechanical behaviour of rock and rock masses. 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. The complete isrm suggested methods for rock characterization, testing and monitoring. Over the years, this system has been successively re fined as more case records have been examined and the reader should be aware that bieniawski has made significant changes in the. Insitu characterization of rocks 4 rock mass is a volume of rocks intersected by discontinuities.
Characterization is the process of giving numerical values to rock mass features such as joint density, joint roughness, rock type. Jan 25, 2007 although rock mechanics addresses many of the rock mechanics issues which arise in underground mining engineering, it is not a text exclusively for mining applications. Engineering rock mechanics is the discipline used to design structures built in rock. It involves measurement of the stability of rock strata and soil deposited within the minedout artificial voids. 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. The rock quality designation rqd is a commonly used index for. The rqd is an index of rock quality in which a modified core recovery per. Rocky ground is rock mass subjected to stresses and ground water. What is the bearing capacity of rock on surface an at depths. Standard test method for determining rock quality designation. Division geotechnical manual which is as described by. Determination and applications of rock quality designation rqd article pdf available in journal of rock mechanics and geotechnical engineering 83 march 2016 with 4,380 reads.
Physical properties of intact rocks, stresses and strains, thermal, hydraulic and mechanical properties of rocks and rock masses, applications of theory of elasticity in rock mechanics, viscoelasticity, rock discontinuities, hemispherical projection methods, in situ stresses and stress measurements, rock slope. Pdf rock quality designation rqd, was introduced by don deere in the mid1960s as a means of using diamond core to classify rock for engineering. Determination and applications of rock quality designation rqd. A proper description of rock obtained in drill cores is a valuable aid to the engineering geologist in determining the properties of bedrock with regard to rock slope and structure foundation design.
Rock mass rating bieniawski 1976 published the details of a rock mass classification called the geomechanics classification or the rock mass rating rmr system. Assessment of the quality of rock mass rqd rock quality designation, table 7. Response of rocks to applied loads earth materials rocks. A number in parentheses indicates the year of last reapproval. What is the modulus of elasticity of rock and how to get it. The later rock classification systems for engineering purposes developed by bieniawski 1973 and by barton et al. Rock mechanics is a field of applied science which has become recognised as a coherent engineering discipline within the last two decades. 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.
Pdf determination and applications of rock quality designation. American society for testing and materials reprinted from the. 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. Engineers and geologists in the petroleum industry will find petroleum related rock mechanics, 2e, a powerful resource in providing a basis of rock mechanical knowledge a knowledge which can greatly assist in the understanding of field behavior, design of test programs and the design of field operations. Applications of theory of elasticity in rock applications of theory of elasticity in rock mechanics 1 free ebooks pdf for applications of theory of elasticity in rock mechanics 1, this is document about. Since in many cases rock quality designation rqd is the only rock mass. Rqd was intended as more than an index of fracture spacing.
Petroleum related rock mechanics, volume 53 2nd edition. The engineering geologist is responsible for the determination of rqd. Use and abuse of rqd in underground mine design springerlink. Rock quality designation, rqd, was introduced by deere as a form of modified core. Rqd even though they possess the requisite 4 in, 100mm length. Active standard astm d6032 d6032m developed by subcommittee. A rock mass rating system provides a method of incorporating some of the complex mechanics of actual rocks into engineering design.
He is the author of two books and has published more than 100 technical papers. Rock mechanics problems how will rock react when put to mens use. Determining rock quality designation rqd of rock core1 this standard is issued under the. Moreover, the system was the first to enable estimation of rock mass properties, such as the modulus of deformation, in addition to providing tunnel support guidelines and the standup time of underground excavations.
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. This book is the result of the experience of the writer in teaching. The rqd in percent is obtained by dividing the sum of all the. Rock mechanics is the study of geotechnical responses of geological phenomena. Highquality rock has an rqd of more than 75%, low quality of less than 50%. Engineering geology, esa, faculty of geoinformation. Depending on the rqd only a rock mass quality was assigned to a. Introduction to rock mechanics 1 the historical development of rock mechanics 1. Rock quality designation, rqd, was introduced by deere as a form of modified. Rock quality designation an overview sciencedirect topics. Highquality rock has an rqd of more than 75%, low quality of less than 50% table 1. It consists of a body of knowledge of the mechanical properti. 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. American society for testing and materials reprinted from.