2013 Session: 751

• FINITE ELEMENT MODELLING OF FRP-REINFORCED CONCRETE FLEXURAL ELEMENTS INSTALLED WITH PROTECTED FIBER OPTIC SENSORS
  Abstract: Fiber Optic Sensors (FOS) for structural health monitoring applications in civil infrastructure such as bridges is gaining popularity because of their durability and accuracy. Fibre reinforced polymer (FRP) is also being increasingly used as reinforcements in concrete structures to benefit from its high strength and non-corrosive characteristics. For efficient installation and protection of FOS in FRP-reinforced structures, its is proposed that the bare fibre FOS is preinstalled in a supplemental FRP bar of appropriate length which can be attached to a main reinforcing bar at the site prior to pouring of concrete. The objective of this article is to develop a numerical model of a FRP reinforced concrete beam installed with an FOS strain sensor on a supplemental bar, and correlate it with the experimental tests conducted to assess the performance of the system. Beams of two different configurations were tested in three point bending. The results obtained from the present and available experimental data are compared to a detailed numerical model with different parameters for strain level, displacement, and bond stress. In the numerical analyses, two types of plasticity models; concrete smeared crack (CSC) and concrete damage plasticity (CDP) were applied. In addition, the fracture strain-stress of FRP is investigated. The results show that the outcomes from the damage plasticity model is more reasonable and in good agreement with experimental results. Also it was found that the suggested bond strength in the existing codes is quite conservative.
  Authors: Rahmatian, Arash; Bagchi, Ashotush; Nokken, Michelle R.
  Authors: Rahmatian, Arash; Bagchi, Ashotush; Nokken, Michelle R.
  Year: 2013
  Document Type: Paper
  Subject: Bridges and Other Structures
  Session: 751
  Paper Number: 13-2226
• Structural Evaluation Against Floods and Earthquakes of Historic Sivas Kesikkopru Bridge in Turkey.
  Abstract: Most of the highway bridges that are in use today are most likely constructed in the 20th century with an average age of 45 to 50 years. Structurally deficient and functionally absolute bridges constitute about 10 to 20 percent some of them occasionally collapsing causing life and economical losses. Building sustainable bridges is a major task today while some historic bridges still stand still to the centuries. Kesikkopru Bridge located in Sivas province of Turkey, which was built in 1292, is an outstanding example to sustainable bridges. The stone arch bridge constructed in the Seljuk era is about 326 meters long with 19 arches and has been the focus of this paper. Measurement of structural dimensions in the field, truck loading analysis using nonlinear compression line analysis, ambient vibration testing, finite element modeling, 500 year return period flood water dynamic modeling, and earthquake response spectrum analysis have been conducted to assess the structural characteristics, response to natural disasters and traffic loads. The results showed that the bridge remains close to linear range during earthquakes and floods and has been overdesigned for vehicle loads. Simple hand calculations and typical dimension ratios obtained from the bridge provide hints for stone bridges being sustainable for over 7 centuries of life span. The authors debate building overdesign structures might better optimize the resources for sustainable bridges that require lower maintenance and have longer service life with higher level of structural safety. After all, building over safe bridges might also be more economical in the long run.
  Authors: Turer, Ahmet; Sert, Halide
  Authors: Turer, Ahmet; Sert, Halide
  Year: 2013
  Document Type: Paper
  Subject: Bridges and Other Structures
  Session: 751
  Paper Number: 13-3040
• NOVEL PROBABILISTIC APPROACH TO DAMAGE IDENTIFICATION OF BRIDGE PIERS POST VESSEL COLLISION BASED ON VIBRATION MEASUREMENTS
  Abstract: Barge-bridge collision has been considered a major contributor to bridge damages in the United States. Most barge-bridge collisions usually may cause partial damage of bridges that may be invisible but threaten the bridge safe operation. After each collision accident, the bridge and the navigation waterway are usually closed for inspection and assessment of the impact of the collision on the bridge structural integrity. This can lead to significant economic losses due to substantial traffic delay or detour. Quick and reliable assessment of bridge post-collision condition can minimize those economic losses. This paper introduces a novel probabilistic approach to bridge post-collision condition assessment based on Bayesian probabilistic framework, which is aimed to promptly identify collision damages and rigorously address associated uncertainties by using real-time vibration-based measurement data. The presented approach is the first attempt to incorporate the realistic bridge finite element model into an advanced statistical sampling method of the transitional Markov chain Monte Carlo to draw a sequence of statistical samples that can be used to approximate the updated probabilistic distributions of damage extents and locations for decision-making. The applicability and effectiveness of the proposed approach are illustrated by using a simulation example of a prototype bridge. Simulation results indicate that the proposed approach has potential capacity for determining the bridge damage extent and location and their statistical characteristics. Finally, the future research need for practical application of the proposed approach is discussed.
  Authors: Zheng, Wei; Chen, Yung-Tsang
  Authors: Zheng, Wei; Chen, Yung-Tsang
  Year: 2013
  Document Type: Paper
  Subject: Bridges and Other Structures
  Session: 751
  Paper Number: 13-3286
• Optimization of Design Details in Orthotropic Steel Decks Subjected to Static and Fatigue Loads
  Abstract: In recent decades, orthotropic steel decks (OSDs) have been routinely incorporated in long span bridges. Employment of cutouts in diaphragms (or sub-floorbeams) that the OSDs frame into is the most widely used configuration to reduce stress concentration, improve fatigue performance, and control crack propagation. However, the capital cost of cutout fabrication in the United States is relatively high and may not be economically feasible. There is a need to study cost-effective modified design details without cutouts and to compare their corresponding flexural and fatigue performance against current design details that utilize cutouts.In this paper, alternative design details (e.g., deck ribs welded directly to the transverse diaphragms using full-penetration welds) utilizing thicker deck plates, but without cutouts, was investigated for potential improvements with respect to fatigue resistance and capital cost. A parametric study was conducted using calibrated finite element models of a portion of the Bronx-Whitestone Bridge in New York City to study the effects of cutouts, deck plate thickness, and other important parameters on fatigue performance. Various traffic load combinations and truck types were considered using an elaborate Weight-In-Motion (WIM) database. Results detail equivalent stress ranges at critical locations in the OSDs that were calculated to quantitatively estimate fatigue lives for two orthotropic deck models; one containing cutouts and one with the cutouts removed. Based on these comparisons, recommendations related to overall structural performance are made to ensure a safe and rational design for various OSD options in long span bridges.
  Authors: Xia, Ye; Nassif, Hani; Hwang, Eui-Seung; Linzell, Daniel G.
  Authors: Xia, Ye; Nassif, Hani; Hwang, Eui-Seung; Linzell, Daniel G.
  Year: 2013
  Document Type: Paper
  Subject: Bridges and Other Structures
  Session: 751
  Paper Number: 13-4623
  Practice-Ready: Yes
• FINITE ELEMENT MODELLING OF FRP-REINFORCED CONCRETE FLEXURAL ELEMENTS INSTALLED WITH PROTECTED FIBER OPTIC SENSORS
  Authors: Rahmatian, Arash
  Authors: Rahmatian, Arash
  Year: 2013
  Document Type: Presentation
  Subject: Bridges and Other Structures
  Session: 751
  Paper Number: 13-2226
• Optimization of Design Details in Orthotropic Steel Decks Subjected to Static and Fatigue Loads
  Authors: Xia, Ye
  Authors: Xia, Ye
  Year: 2013
  Document Type: Presentation
  Subject: Bridges and Other Structures
  Session: 751
  Paper Number: 13-4623