{"id":67,"date":"2015-05-11T16:19:08","date_gmt":"2015-05-12T00:19:08","guid":{"rendered":"http:\/\/research.engineering.ucdavis.edu\/see\/?page_id=67"},"modified":"2015-05-11T16:19:08","modified_gmt":"2015-05-12T00:19:08","slug":"wheel-load-distributions-in-multi-cell-box-girder-bridges","status":"publish","type":"page","link":"https:\/\/research.engineering.ucdavis.edu\/see\/wheel-load-distributions-in-multi-cell-box-girder-bridges\/","title":{"rendered":"Wheel Load Distributions in Multi-Cell Box Girder Bridges"},"content":{"rendered":"<p>Although a simplified girder-line analysis is permitted by the <em>1998 AASHTO LRFD Bridge Design Specifications<\/em> for the design of highway bridges in the US, fairly tight constraints are imposed on a number of important design parameters. For the case of box-girder bridges, which are a common type of bridges in California, the AASHTO LRFD Specifications imposes limitations on the curvature of the bridge, variation of deck-width, skew of bridge support, girder spacing etc. More specifically, the simplified 2D girder-line analysis is limited to bridges with:<\/p>\n<table border=\"0\" width=\"100%\">\n<tbody>\n<tr>\n<td width=\"100%\">\n<ul>\n<li><em><span style=\"font-size: large;\">Constant Deck Width<\/span><\/em><\/li>\n<\/ul>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"100%\">\n<ul>\n<li><span style=\"font-family: Arial;\"><em><span style=\"font-size: large;\">Number of Girders Great Than 4<\/span><\/em><\/span><\/li>\n<\/ul>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"100%\">\n<ul>\n<li><em><span style=\"font-size: large;\">Parallel Girders of Approximately Equal Stiffness<\/span><\/em><\/li>\n<\/ul>\n<\/td>\n<\/tr>\n<tr>\n<td width=\"100%\">\n<ul>\n<li><em><span style=\"font-size: large;\">Plan Curvature Less Than 12 Degrees<\/span><\/em><\/li>\n<\/ul>\n<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><span style=\"font-size: large;\">For bridges with parameters outside of these constraints, design of such structures requires a more refined 3D analysis, either by finite element or grillage analysis. The objective of this project is to conduct a parametric study to examine the limitations imposed by the current <em>AASHTO LRFD Specifications<\/em> and determine if these limitations can be broadened for typical bridge geometry in California. Preliminary results indicated that the current <em>AASHTO LRFD Specifications<\/em> is conservative with respect to the distribution of bending moments and shear forces to individual girders, and constraints imposed by the <em>Specifications<\/em> can be extended.<\/span><\/p>\n<p><i><span style=\"text-decoration: underline;\"><span style=\"font-size: large;\">Key publications<\/span><\/span><\/i><\/p>\n<ul>\n<li><span style=\"font-size: large;\">Song, Shin-Tai, Y. H. Chai and Susan E. Hida (2003), <i>&#8220;Live Load Distribution Factors for Concrete Box-Girder Bridges&#8221;,<\/i> Journal of Bridge Engineering, ASCE, Vol. 8, No. 5, pp. 273-280.<\/span><\/li>\n<\/ul>\n<p><span style=\"font-size: large;\">For a PowerPoint presentation of the project, <a href=\"http:\/\/retrocee.engr.ucdavis.edu\/faculty\/chai\/Research\/AASHTO%20LRFD\/LrfdPresentation_files\/frame.htm\">click here<\/a>.<\/span><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Although a simplified girder-line analysis is permitted by the <em>1998 AASHTO LRFD Bridge Design Specifications<\/em> for the design of highway bridges in the US, fairly tight constraints are imposed on a number of important design parameters. For the case of box-girder bridges, which are a common type of bridges in  \u2026 <a href=\"https:\/\/research.engineering.ucdavis.edu\/see\/wheel-load-distributions-in-multi-cell-box-girder-bridges\/\"> Continue reading <span class=\"meta-nav\">&rarr; <\/span><\/a><\/p>\n","protected":false},"author":10,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-67","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/research.engineering.ucdavis.edu\/see\/wp-json\/wp\/v2\/pages\/67","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/research.engineering.ucdavis.edu\/see\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/research.engineering.ucdavis.edu\/see\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/research.engineering.ucdavis.edu\/see\/wp-json\/wp\/v2\/users\/10"}],"replies":[{"embeddable":true,"href":"https:\/\/research.engineering.ucdavis.edu\/see\/wp-json\/wp\/v2\/comments?post=67"}],"version-history":[{"count":1,"href":"https:\/\/research.engineering.ucdavis.edu\/see\/wp-json\/wp\/v2\/pages\/67\/revisions"}],"predecessor-version":[{"id":68,"href":"https:\/\/research.engineering.ucdavis.edu\/see\/wp-json\/wp\/v2\/pages\/67\/revisions\/68"}],"wp:attachment":[{"href":"https:\/\/research.engineering.ucdavis.edu\/see\/wp-json\/wp\/v2\/media?parent=67"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}