published_or_final_version / Civil Engineering / Doctoral / Doctor of Philosophy

No description available.

published_or_final_version / Civil Engineering / Doctoral / Doctor of Philosophy

No description available.

No description available.

No description available.

The western and northern parts of South Florida have shallow layers of organic and plastic soils under existing roads. These roads often exhibit large amount of cracking and distortion in a short period of time. Traditional repairs are often not practical due to high costs and extended construction time. In an effort to develop rehabilitation strategies that could be strictly applied to the surface layer, a pilot test site was selected along the alignment of SR 15/US 98 in northwest Palm Beach County, where severe pavement distresses were observed due to the presence of thick organic layers. PaveTrac MT-1, GlasGrid 8501, PetroGrid 4582, and ARMI were used as promising asphalt reinforcing products in 24 experimental pavement sections, including 8 control sections without any reinforcement. A comprehensive field testing and monitoring program involving FWD, rut and ride quality measurements was conducted at the preconstruction, 6-month post-construction, and 18-month post-construction stages. Due to large variability in the sub-surface conditions, a statistics-based data analysis protocol was developed for performance evaluation and relative comparisons of the test sections and, in turn, reinforcing products. Post construction data from both 6 months and 18 months demonstrated that stiffness of reinforced sections were significantly higher than the control sections. Procedures were developed to identify and statistically quantify the benefits derived from the reinforcements only, so that the relative performance of various products could be monitored over time. Based on the field testing data available to date, a framework was developed in this study for the prediction of pavement life, which is essential for conducting a detailed Life Cycle Analysis / by Alex Lima-Arie. / Thesis (M.S.C.S.)--Florida Atlantic University, 2010. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2010. Mode of access: World Wide Web.

Bridges consisting of multiple parallel pre-stressed and pre-fabricated Tee-beams topped by a cast-on-site concrete slab are often a cost-effective way of constructing simply-supported and multi-span bridge structures in many countries world-wide. For the design of these bridges computer models are often utilised. This thesis presents a comprehensive discussion of modelling issues encountered in the practical design work on this bridge type. A chapter on the modelling of various loading conditions is followed by a detailed discussion of the modelling of the longitudinal load bearing system, the Tee-beams, and the lateral load-bearing system, the roadway slab. A summary of commonly used bridge systems in various countries is also included. All this material is presented considering design code requirements in various internationally used specifications. The information included in this thesis has been used to define specifications for the implementation of a software tool to support the design of so-called Super-Tee bridges. A summary of these specifications is given in the conclusions of this thesis. Material included in this thesis has also been published in the following conference proceedings: Pircher G., Pircher M. (2004) “Computer-aided design and analysis of multiple Tee-beam bridges”, Proceedings: Fifth Austroads Bridge Conference, Hobart, Australia, on CD Pircher M, Pircher G, Wheeler A (2006) “Automated Analysis and Design of Super-Tee Bridges”, Proceedings: Sixth Austroads Bridge Conference, Perth (in publication) / Master of Engineering (Hons)

Large numbers of 1950's vintage conventionally reinforced concrete (CRC) bridges remain in-service in the national bridge inventory. Many of these bridges are lightly reinforced for shear. Evaluation of these bridges to prevent unnecessary and costly repairs requires refined analytical techniques. This dissertation presents finite element (FE) modeling and comparisons of various analytical methods for predicting capacity of CRC girders typical of reinforced concrete deck girder (RCDG) bridges. Analyses included bridge-system load distribution, member capacity prediction, and consideration of corrosion damage for strength deterioration. Two in-service RCDG bridges were inspected and instrumented to measure response under known load configurations. Load distribution was developed for the bridges based on the field data. Comparisons with AASHTO factors indicated the design factors for load distribution are conservative. Load distribution of the tested bridges was numerically obtained using FE analysis. The comparisons between predicted results and field-test data indicated the elastic FE analysis can be used for modeling of cracked RCDG bridges to predict load distribution factors for more accurate bridge evaluation. Analyses were performed for a large set of full-size RCDG, designed to reflect 1950's vintage details, and tested using various loading configurations. Four different analysis methods were used to predict the capacity of the specimens considering details of various stirrup spacing, debonded stirrups, flexural-bar cutoff, anchorage of flexural reinforcing, and moving supports. Nonlinear FE analyses were performed to predict behavior of two groups of experimental reinforced concrete (RC) specimens. Two different span-to-depth ratios were included: 2.0 and approximately 3.0. Concrete confinement effects were included in the material modeling. A quasi-displacement control technique was developed to reduce solution times. The FE predicted results correlated well with the experimental data. FE modeling techniques were developed to isolate different contributions of corrosion damage to structural response of experimental RC beams designed to produce diagonal-tension failures. Corrosion-damage parameters included concrete cover spalling; uniform stirrup cross-sectional loss; local stirrup cross-sectional loss due to pitting; and debonding of corrosion-damaged stirrups from the concrete. FE analyses were performed including both individual and combined damages. The FE results matched experimental results well and quantitatively estimated capacity reduction of the experimental specimens. / Graduation date: 2005 / Best scan available.

Not available / text