{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/30885"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/30885","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"On the shear strength of polyurethane coated railroad ballast","abstract":"Unbound nature of railroad ballast aggregates causes abrasion and degrada- tion predicaments due to heavy train axle loads. Polyurethane reinforcement of ballast layer is a candidate solution to these problems. However, not many polyurethane reinforcement applications have been studied until the begin- ning of last decade. Therefore, the technology requires considerable research e orts to fully develop. As part of this thesis study research, direct shear testing was undertaken for two di erent railroad ballast aggregates, granite and limestone. Both aggregate materials satis ed the AREMA No. 24 railroad ballast gradation requirements. Although the unbound granite samples showed higher shear strength properties than the unbound limestone samples, polyurethane rein- forcement increased shear strengths of the limestone aggregate samples more than the granite aggregate samples in direct shear (shear box) tests. The granite samples had somewhat of a coarser gradation when compared to the size distribution of the limestone samples. An image aided discrete element modeling approach was used to simulate the shear box tests and calculate number of particle contacts and sample porosities for both the granite and limestone gradations. The simulation results showed that even though the di erences in porosity were only in the order of 2% to 3%, the number of particle contacts for the limestone samples was 50% more than that for the granite samples. In conclusion, number of particle contacts in an assembly of aggregates coated with polyurethane was found to be an important factor contributing to the shear strength properties of chemically bonded ballast aggregate layers.","abstract_html":"Unbound nature of railroad ballast aggregates causes abrasion and degrada- tion predicaments due to heavy train axle loads. Polyurethane reinforcement of ballast layer is a candidate solution to these problems. However, not many polyurethane reinforcement applications have been studied until the begin- ning of last decade. Therefore, the technology requires considerable research e orts to fully develop. As part of this thesis study research, direct shear testing was undertaken for two di erent railroad ballast aggregates, granite and limestone. Both aggregate materials satis ed the AREMA No. 24 railroad ballast gradation requirements. Although the unbound granite samples showed higher shear strength properties than the unbound limestone samples, polyurethane rein- forcement increased shear strengths of the limestone aggregate samples more than the granite aggregate samples in direct shear (shear box) tests. The granite samples had somewhat of a coarser gradation when compared to the size distribution of the limestone samples. An image aided discrete element modeling approach was used to simulate the shear box tests and calculate number of particle contacts and sample porosities for both the granite and limestone gradations. The simulation results showed that even though the di erences in porosity were only in the order of 2% to 3%, the number of particle contacts for the limestone samples was 50% more than that for the granite samples. In conclusion, number of particle contacts in an assembly of aggregates coated with polyurethane was found to be an important factor contributing to the shear strength properties of chemically bonded ballast aggregate layers.","abstract_has_math":false,"creators":["Boler, Huseyin"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"M.S.","degree_level":"Thesis","degree_discipline":"Civil Engineering","degree_department":null,"school":null,"contributors":["Tutumluer, Erol"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2012,"date_issued":"2012-05-22T00:13:13Z","date_published":"2012-05-22T00:13:13Z","updated_at":"2026-07-22T22:25:29Z","subjects":["Railroad Ballast","Shear Strength","Polyurethane Reinforcement"],"languages":["en"],"rights":["Copyright 2012 Huseyin Boler"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/2142/30885","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Tutumluer, Erol"]},{"key":"dc:creator","label":"Author","values":["Boler, Huseyin"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2012-05-22T00:13:13Z","2012-05"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Civil Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M.S."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Railroad Ballast","Shear Strength","Polyurethane Reinforcement"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2012 Huseyin Boler"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/30885"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Unbound nature of railroad ballast aggregates causes abrasion and degrada- tion predicaments due to heavy train axle loads. Polyurethane reinforcement of ballast layer is a candidate solution to these problems. However, not many polyurethane reinforcement applications have been studied until the begin- ning of last decade. Therefore, the technology requires considerable research e orts to fully develop. As part of this thesis study research, direct shear testing was undertaken for two di erent railroad ballast aggregates, granite and limestone. Both aggregate materials satis ed the AREMA No. 24 railroad ballast gradation requirements. Although the unbound granite samples showed higher shear strength properties than the unbound limestone samples, polyurethane rein- forcement increased shear strengths of the limestone aggregate samples more than the granite aggregate samples in direct shear (shear box) tests. The granite samples had somewhat of a coarser gradation when compared to the size distribution of the limestone samples. An image aided discrete element modeling approach was used to simulate the shear box tests and calculate number of particle contacts and sample porosities for both the granite and limestone gradations. The simulation results showed that even though the di erences in porosity were only in the order of 2% to 3%, the number of particle contacts for the limestone samples was 50% more than that for the granite samples. In conclusion, number of particle contacts in an assembly of aggregates coated with polyurethane was found to be an important factor contributing to the shear strength properties of chemically bonded ballast aggregate layers.","Item withdrawn by Mark Zulauf (zulauf@illinois.edu) on 2012-04-27T15:36:21Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 1 Boler_Huseyin.pdf: 11386223 bytes, checksum: bb6c16640d0dae1ae7b5ba86b0455601 (MD5)","Made available in DSpace on 2012-05-22T00:13:13Z (GMT). No. of bitstreams: 2 Boler_Huseyin.pdf: 11386223 bytes, checksum: bb6c16640d0dae1ae7b5ba86b0455601 (MD5) license.txt: 4061 bytes, checksum: ef0347ecd161ee1af6077f11b1535853 (MD5)"]},{"key":"dc:title","label":"Title","values":["On the shear strength of polyurethane coated railroad ballast"]}]}],"canonical_facts":{"dc:contributor":["Tutumluer, Erol"],"dc:creator":["Boler, Huseyin"],"dc:date":["2012-05-22T00:13:13Z","2012-05"],"dc:description":["Unbound nature of railroad ballast aggregates causes abrasion and degrada- tion predicaments due to heavy train axle loads. Polyurethane reinforcement of ballast layer is a candidate solution to these problems. However, not many polyurethane reinforcement applications have been studied until the begin- ning of last decade. Therefore, the technology requires considerable research e orts to fully develop. As part of this thesis study research, direct shear testing was undertaken for two di erent railroad ballast aggregates, granite and limestone. Both aggregate materials satis ed the AREMA No. 24 railroad ballast gradation requirements. Although the unbound granite samples showed higher shear strength properties than the unbound limestone samples, polyurethane rein- forcement increased shear strengths of the limestone aggregate samples more than the granite aggregate samples in direct shear (shear box) tests. The granite samples had somewhat of a coarser gradation when compared to the size distribution of the limestone samples. An image aided discrete element modeling approach was used to simulate the shear box tests and calculate number of particle contacts and sample porosities for both the granite and limestone gradations. The simulation results showed that even though the di erences in porosity were only in the order of 2% to 3%, the number of particle contacts for the limestone samples was 50% more than that for the granite samples. In conclusion, number of particle contacts in an assembly of aggregates coated with polyurethane was found to be an important factor contributing to the shear strength properties of chemically bonded ballast aggregate layers.","Item withdrawn by Mark Zulauf (zulauf@illinois.edu) on 2012-04-27T15:36:21Z Item was in collections: University of Illinois Theses & Dissertations (ID: 1) No. of bitstreams: 1 Boler_Huseyin.pdf: 11386223 bytes, checksum: bb6c16640d0dae1ae7b5ba86b0455601 (MD5)","Made available in DSpace on 2012-05-22T00:13:13Z (GMT). No. of bitstreams: 2 Boler_Huseyin.pdf: 11386223 bytes, checksum: bb6c16640d0dae1ae7b5ba86b0455601 (MD5) license.txt: 4061 bytes, checksum: ef0347ecd161ee1af6077f11b1535853 (MD5)"],"dc:identifier":["http://hdl.handle.net/2142/30885"],"dc:language":["en"],"dc:rights":["Copyright 2012 Huseyin Boler"],"dc:subject":["Railroad Ballast","Shear Strength","Polyurethane Reinforcement"],"dc:title":["On the shear strength of polyurethane coated railroad ballast"],"dc:type":["text"],"thesis:degree_discipline":["Civil Engineering"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["M.S."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:29Z"}