2012 Issue

70 Jordan River Bridge Abutments — November 2010. Access Road Bridge Abutments — November 2010. proximately 190 feet. Two prestressed concrete girder bridges with spans of 63 feet will carry traffic over the access road west of the river. The geotechnical report for the project recommended that the bridges be supported on deep foundations. The pres- ence of relatively deep compressible clay underlain by dense sand and gravel caused engineers to favor the use of steel pipe piles driven with closed ends. The bridge designers opted to use 16-inch diameter pile founda- tions for the Jordan River bridges and 12.75-inch diameter piles for the bridges over the access road. The foundation design at each abutment incorporates ten to twelve piles driven to depths of about 100 to 115 feet below the natural ground surface. The steel pipe used for piles at both bridge sites has a wall thickness of 0.5 inch and yield strength of at least 65 ksi. The contractor drove the piles for the Jordan River bridges in April and May 2010, and built the bridge approach embankments and walls around the piles subsequent to pile installation. The plans and specifications required that soil resistance of at least 640 kips be verified during pile driving. After the first piles were driven to the estimateddepths, signal matching analyses of dynamic pile test data estimated driving resistance values ranging from 642 to 703 kips. At the access road bridges, the contractor opted to construct the mechanically stabilized earth walls prior to pile driving, building the fill around corrugated metal pipe shells placed at each pile location. The piles will be installed through the shells at a later date.  Brad Price is a principal and the president of RB&G Engineering, Inc. in Provo, Utah, and the manager of the geotechnical division at the company. He provided geotechnical management ser vices on the Mountain View Corridor project. For over 20 years, he worked closely with the late Dr. Ralph L. Rollins in a number of soil and foundation projects throughout the Intermountain West. He received a Bachelors of Science in civil engineering from Brigham Young University, where he also completed graduate studies in geotechnical engineering. A registered professional engineer in Utah and Idaho, Mr. Price has over 35 years experience in pavement evaluation and design; foundation design for bridges, airports, commercial buildings and other structures; design of earth dams and dam safety studies; design of MSE walls; bridge abutment design; environmental assessment studies; and geotechnical consulting for highway reconstruction and improvement projects. He is presently a member of the American Society of Civil Engineers (ASCE) and served as the geotechnical chair for the ASCE Utah Section (1994). Brad has also participated on several independent review boards, taught university classes, published articles for professional journals, and made presentations for national and state conferences. Robert Johnson has nine years of geotechnical engineering experience a n d h a s b e e n a r e g i s t e r e d professional engineer since 2007. He has a Bachelors of Science degree in civil engineering and a Masters of Science degree with a geotechnical emphasis from Brigham Young University in Provo, Utah. Robert is a senior design engineer at RB&G Engineering, Inc., and served as a geotechnical design engineer for theMountain ViewCorridor Project. His assignments at the company involve design analysis and reports for geotechnical studies, liquefaction and lateral spread analyses, seismic stability and deformation analyses for earth dams and water storage projects, supervision of subsurface investigations, and foundation analyses for projects throughout Utah and Nevada. Prior to joining RB&G, Robert assisted in a full-scale pile load test project funded by the National Science Foundation. Brandon Horrocks received his Bachelors of Science degree in civil engineering from the University of Utah in Salt Lake City, Utah, and has eight years experience at RB&G Engineering, Inc. He served as a geotechnical design engineer on the Mountain View Corridor project and is a professional registered engineer in Utah. His responsibilities at the company include geotechnical design for bridge structures, retaining walls, roadway and pavement; geotechnical construction oversight; quality assurance inspection services; and construction management. Jake Price received his Bachelors of Science degree in mechanical engineering from Utah State University in Logan, Utah, and will receive the Masters of Science degree in civil engineering from Brigham Young University in Provo, Utah. His professional engineer status has also been approved. Mr. Price is currently serving as the field engineer at Mountain View Corridor, where he is responsible for instrumentation monitoring operations. His responsibilities at RB&G Engineering, Inc. include field management for geotechnical investigations and quality assurance inspection services during construction. GEOTECHNICAL | continued from page 69