{"id":110,"date":"2026-05-05T05:41:36","date_gmt":"2026-05-05T05:41:36","guid":{"rendered":"http:\/\/3.104.199.245\/?page_id=110"},"modified":"2026-08-24T11:28:59","modified_gmt":"2026-08-24T01:28:59","slug":"theory-literature","status":"publish","type":"page","link":"https:\/\/www.stadss.com.au\/?page_id=110","title":{"rendered":"Theory\/Literature"},"content":{"rendered":"\n<h1 class=\"wp-block-heading has-text-align-center\">Theory\/Literature<\/h1>\n\n\n\n<div class=\"wp-block-group has-global-padding is-layout-constrained wp-block-group-is-layout-constrained\">\n<p class=\"has-text-align-left wp-block-paragraph\">StADSS is the\u00a0<strong><span style=\"text-decoration: underline;\">St<\/span><\/strong>ochastic\u00a0<strong><span style=\"text-decoration: underline;\">A<\/span><\/strong>pproach to\u00a0<strong><span style=\"text-decoration: underline;\">D<\/span><\/strong>iscontinuity\u00a0<strong><span style=\"text-decoration: underline;\">S<\/span><\/strong>hear\u00a0<strong><span style=\"text-decoration: underline;\">S<\/span><\/strong>trength. We characterise the shear strength of natural rock joints at full scale, bypassing the well known scale effects. StADSS\u00a0represents\u00a0a fundamental shift in how the shear strength of natural rock discontinuities is predicted.\u00a0Its core principle is to capture roughness information directly at the scale of the project to bypass the well known scale effect; and to apply rigorous statistics and mechanics to predict the discontinuity shear strength. The statistical properties of surveyed traces (referred to as seed trace) are used to reconstruct\u00a0many\u00a03D synthetic surfaces\u00a0through rigorous\u00a0random field modelling. These synthetic surfaces preserve key statistical descriptors of the seed trace, most importantly the standard deviation of gradients, and are produced at engineering scale allowing the method to work\u00a0directly at field scale\u00a0without downscaling or empirical scale corrections; bypassing any scale effects. Each reconstructed surface is sheared virtually using a\u00a0semi\u2011analytical\u00a0mechanistic model\u00a0(called NDSS, developed at the University of Newcastle), which triangulates the synthetic morphology into\u00a0facets, identifies which ones are \u201cactive\u201d,\u00a0and estimates\u00a0peak and residual shear strength from rock strength parameters, without the need for an empirical calibration factor. By repeating this over 100+ realisations in a Monte Carlo manner,\u00a0StADSS\u00a0yields a\u00a0probabilistic strength distribution, rather than a single deterministic value.\u00a0<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The novelty of&nbsp;StADSS&nbsp;lies in several breakthroughs:&nbsp;<\/p>\n\n\n\n<ul class=\"wp-block-list\">\n<li>It bypasses the scale effect on roughness: one of rock mechanics\u2019 longstanding unresolved problems, through statistical reconstruction at full discontinuity scale.&nbsp;&nbsp;<\/li>\n\n\n\n<li>It is based on rigorous statistical and mechanistic modelling,<\/li>\n\n\n\n<li>It does not rely on ill-defined or subjective roughness predictors, but on the full geometrical profile of the seed trace,<\/li>\n\n\n\n<li>It can predict peak and residual shear strength of very rough surfaces where traditional tangent-based models are mathematically limited, returning negative values of shear strength, and<\/li>\n\n\n\n<li>Its probabilistic formulation efficiently captures uncertainty about discontinuity morphology and variability of material strength (an often-overlooked aspect in rock mechanics) and allows efficient sensitivity analyses.<\/li>\n<\/ul>\n\n\n\n<p class=\"wp-block-paragraph\">StADSS has been validated in the laboratory on a 2m x 2m rough surface and tested in the field. StADSS has been developed with the support of PSM, Geotechnical Consultants, Sydney.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">Together, these advances establish StADSS as a transformative, scale\u2011independent&nbsp;methodology&nbsp;capable of delivering shear strength predictions where classical models fail or are inapplicable.<br><br><strong>Downloads:<\/strong><\/p>\n\n\n\n<div class=\"wp-block-columns is-style-default is-layout-flex wp-container-core-columns-is-layout-80868740 wp-block-columns-is-layout-flex\">\n<div class=\"wp-block-column is-layout-flow wp-block-column-is-layout-flow\" style=\"flex-basis:100%\">\n<details class=\"wp-block-details is-layout-flow wp-block-details-is-layout-flow\"><summary>PDF Lecture\/Presentation: Invited Lecture at the 2026 AGS Australian Rock Mechanics Conference, Melbourne.<\/summary>\n<div data-wp-interactive=\"core\/file\" class=\"wp-block-file\"><object data-wp-bind--hidden=\"!state.hasPdfPreview\" hidden class=\"wp-block-file__embed\" data=\"https:\/\/www.stadss.com.au\/wp-content\/uploads\/2026\/07\/Invited-Lecture-at-the-2026-AGS-Australian-Rock-Mechanics-Conference-Melbourne-2.pdf\" type=\"application\/pdf\" style=\"width:100%;height:600px\" aria-label=\"Embed of Invited Lecture at the 2026 AGS Australian Rock Mechanics Conference, Melbourne.\"><\/object><a id=\"wp-block-file--media-32097bac-404e-44e8-bc20-aa0ef8a5c544\" href=\"https:\/\/www.stadss.com.au\/wp-content\/uploads\/2026\/07\/Invited-Lecture-at-the-2026-AGS-Australian-Rock-Mechanics-Conference-Melbourne-2.pdf\">Invited Lecture at the 2026 AGS Australian Rock Mechanics Conference, Melbourne<\/a><a href=\"https:\/\/www.stadss.com.au\/wp-content\/uploads\/2026\/07\/Invited-Lecture-at-the-2026-AGS-Australian-Rock-Mechanics-Conference-Melbourne-2.pdf\" class=\"wp-block-file__button wp-element-button\" download aria-describedby=\"wp-block-file--media-32097bac-404e-44e8-bc20-aa0ef8a5c544\">Download<\/a><\/div>\n<\/details>\n<\/div>\n<\/div>\n\n\n\n<p class=\"wp-block-paragraph\"><strong>References<\/strong><br>\u2022 Casagrande, D., Buzzi, O., Giacomini, A., Lambert, C. and Fenton, G. (2018), \u2018A New Stochastic Approach to Predict Peak and Residual Shear Strength of Natural Rock Discontinuities\u2019,&nbsp;<em>Rock Mechanics and Rock Engineering<\/em>, vol. 51(1), pp. 69\u201399.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/link.springer.com\/article\/10.1007\/s00603-017-1302-3\">https:\/\/link.springer.com\/article\/10.1007\/s00603-017-1302-3<\/a><br><br>\u2022 Buzzi, O. and Casagrande, D. (2018), \u2018A step towards the end of the scale effect conundrum when predicting the shear strength of large in situ discontinuities\u2019, <em>International Journal of Rock Mechanics and Mining Sciences<\/em>, vol. 105, pp. 210\u2013219.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/www.sciencedirect.com\/science\/article\/abs\/pii\/S1365160917309383\">https:\/\/www.sciencedirect.com\/science\/article\/abs\/pii\/S1365160917309383<\/a><br><br>\u2022 Jeffery, M., Huang, J., Fityus, S., Giacomini, A. and Buzzi, O. (2021), \u2018A rigorous multiscale random field approach to generate large scale rough rock surfaces\u2019,&nbsp;<em>International Journal of Rock Mechanics and Mining Sciences<\/em>, vol. 142, art. no. 104716.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/www.sciencedirect.com\/science\/article\/abs\/pii\/S1365160921001027\">https:\/\/www.sciencedirect.com\/science\/article\/abs\/pii\/S1365160921001027<\/a><br><br>\u2022 Jeffery, M., Crumpton, M., Fityus, S.G., Huang, J., Giacomini, A. and Buzzi, O. (2022), \u2018A Shear Device with Controlled Boundary Conditions for Very Large Nonplanar Rock Discontinuities\u2019,&nbsp;<em>Geotechnical Testing Journal<\/em>, vol. 45(4).<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/dl.astm.org\/gtj\/article\/45\/4\/725\/3448\/A-Shear-Device-with-Controlled-Boundary-Conditions\">https:\/\/dl.astm.org\/gtj\/article\/45\/4\/725\/3448\/A-Shear-Device-with-Controlled-Boundary-Conditions<\/a><br><br>\u2022 Jeffery, M., Huang, J., Fityus, S., Giacomini, A. and Buzzi, O. (2023), \u2018A Large-Scale Application of the Stochastic Approach for Estimating the Shear Strength of Natural Rock Discontinuities\u2019,&nbsp;<em>Rock Mechanics and Rock Engineering<\/em>, vol. 56(8), pp. 6061\u20136078.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/link.springer.com\/article\/10.1007\/s00603-023-03393-1\">https:\/\/link.springer.com\/article\/10.1007\/s00603-023-03393-1<\/a><br><br>\u2022 Buzzi, O., Jeffery, M., Moscato, P.,&nbsp;Grebogi, R.B. and Haque, M.N. (2024), \u2018Mathematical Modelling of Peak and Residual Shear Strength of Rough Rock Discontinuities Using Continued Fractions\u2019,&nbsp;<em>Rock Mechanics and Rock Engineering<\/em>, vol. 57(2), pp. 851\u2013865.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/link.springer.com\/article\/10.1007\/s00603-023-03548-0\">https:\/\/link.springer.com\/article\/10.1007\/s00603-023-03548-0<\/a><br><br>\u2022 Butcher, C., Buzzi, O., Giacomini, A., Bertuzzi, R. and Griffiths, D.V. (2025), \u2018Influence of Roughness Digitisation Error on Predictions of Discontinuity Shear Strength\u2019,&nbsp;<em>Remote Sensing<\/em>, vol. 17(4), art. no. 599.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/www.mdpi.com\/2072-4292\/17\/4\/599\">https:\/\/www.mdpi.com\/2072-4292\/17\/4\/599<\/a><br><br>\u2022 Butcher, C., Buzzi, O., Giacomini, A., Bertuzzi, R., Griffiths, D.V. and Fityus, S. (2025), \u2018Shear Strength of a Large Limestone Discontinuity: In Situ Pull Test and Prediction\u2019,&nbsp;<em>Rock Mechanics and Rock Engineering<\/em>, vol. 58(2), pp. 2203\u20132222.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/link.springer.com\/article\/10.1007\/s00603-024-04270-1\">https:\/\/link.springer.com\/article\/10.1007\/s00603-024-04270-1<\/a><br><br>\u2022 Butcher, C. and Buzzi, O. (2025), \u2018Quantifying Rock Strength Variability Under Different Tests and Failure Modes\u2019,&nbsp;<em>Rock Mechanics and Rock Engineering<\/em>, 59,&nbsp;pp. 1441\u20131454.<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><a href=\"https:\/\/link.springer.com\/article\/10.1007\/s00603-025-04952-4\">https:\/\/link.springer.com\/article\/10.1007\/s00603-025-04952-4<\/a><\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Theory\/Literature StADSS is the\u00a0Stochastic\u00a0Approach to\u00a0Discontinuity\u00a0Shear\u00a0Strength. We characterise the shear strength of natural rock joints at full scale, bypassing the well known scale effects. StADSS\u00a0represents\u00a0a fundamental shift in how the shear strength of natural rock discontinuities is predicted.\u00a0Its core principle is to capture roughness information directly at the scale of the project to bypass the well [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"page-no-gap","meta":{"footnotes":""},"class_list":["post-110","page","type-page","status-publish","hentry"],"jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.stadss.com.au\/index.php?rest_route=\/wp\/v2\/pages\/110","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.stadss.com.au\/index.php?rest_route=\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.stadss.com.au\/index.php?rest_route=\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.stadss.com.au\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.stadss.com.au\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=110"}],"version-history":[{"count":13,"href":"https:\/\/www.stadss.com.au\/index.php?rest_route=\/wp\/v2\/pages\/110\/revisions"}],"predecessor-version":[{"id":361,"href":"https:\/\/www.stadss.com.au\/index.php?rest_route=\/wp\/v2\/pages\/110\/revisions\/361"}],"wp:attachment":[{"href":"https:\/\/www.stadss.com.au\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=110"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}