Engineering Commons^™

Post-Fire Damage Inspection Of Concrete Tunnel Structures, James Viglas

Masters Theses

In general, tunnels are designed with an abundance of safety regarding structural integrity, however, there can be uncertainty related to structural performance after a fire event. The residual condition of a tunnel after a fire is dependent on fire intensity and duration. The goal of this study is to correlate visual and material characteristics of structural and non-structural components of tunnels with fire temperature and exposure time. This can be further related to the residual capacity of structural members in a tunnel, providing insight into safety and overall functionality. Experimental results show that the visual response of materials with heat …

Review Of Innovative Rehabilitation Techniques For Reinforced Concrete Buildings, Demetrius Karoubas

Graduate Theses, Dissertations, and Problem Reports

Building rehabilitation encompasses the act of repairing damaged structural elements, as well as the upgrading of older buildings to bring them up to modern standards. In recent years, due to the extreme economic and environmental cost of new construction, building rehabilitation is gaining ground as the most viable solution to the problem posed by damaged or substandard buildings. With the constant development of new materials with favorable properties and the improvement of our understanding of earthquakes, new rehabilitation techniques are being developed, improving on the efficiency and effectiveness of older ones. Reinforced Concrete (RC) buildings are a type of building …

Experimental And Numerical Study Of Precast Concrete Pipe With Single Elliptical Steel Cage Reinforcement, Abdullah Samir Ramadan

Electronic Thesis and Dissertation Repository

Reinforced concrete pipe (RCP) with single elliptical (SE) reinforcement offers cost savings and is permitted by Canadian and American standards. Yet, its use has not yet gained momentum primarily due to limited knowledge of its structural performance. This study explores the structural behaviour of full-scale 1050 mm and 1200 mm diameter RCP reinforced with SE cold drawn steel wire cage under the Three-Edge Bearing Test. Results indicate that RCP with SE reinforcement designed per current standards did not meet the specified 0.3-mm crack and ultimate load capacity. Hence, pertinent provisions in CSA A257.2 and ASTM C76 for RCP need to …

Performance-Based Design Of Fire-Exposed Reinforced Concrete Elements Using An Equivalent Standard Fire, Robert T. Kuehnen

Electronic Thesis and Dissertation Repository

Fire events represent one of the most severe loading scenarios for reinforced concrete (RC) buildings. In lieu of intensive computational analysis, designers need simplified methods to assess RC members exposed to natural fires. This thesis focuses on the development of a time equivalent (t_e) to replace a natural fire with an equivalent standard fire, allowing for the implementation of existing simplified analysis methods.

The proposed t_e is based on the average internal temperature profile (AITP) that develops in a section during fire. Two AITP t_e are proposed to accurately or conservatively approximate the AITP of …

Evaluation Of 2-Cell Rc Box Culverts, Hossein Sharifi

Theses and Dissertations--Civil Engineering

Reinforced Concrete Box Culverts (RCBCs) are an integral part of the national and international transportation infrastructure. The National Bridge Inventory Standards (NBIS) requires that all bridges, which include culverts with spans ≥ 20 ft. (6.1 m), be load rated for safe load carrying capacity in accordance with the AASHTO Manual for Bridge Evaluation (MBE). In Kentucky, the Transportation Cabinet manages more than 15,500 bridges, of which almost 1,400 are bridge size culverts. Of the 1241 bridge size RCBCs that were being evaluated in Kentucky between 2015 and 2018, 846 were 2-cell culverts (or 68%). The objective in this study is …

Concrete Bridge Girders With Exposed Flexural Reinforcement, Trevor K. Scott

Electronic Thesis and Dissertation Repository

Reinforced concrete highway bridge girders are regularly repaired by replacing deteriorated concrete with new concrete, temporarily exposing the flexural reinforcement. The absence of bond between the concrete and steel at this stage makes it difficult to compute the flexural capacity and the current code criteria provide no guidance to assist practitioners.

The research reported in this thesis rectifies this knowledge gap. A thorough examination is presented of experimental and analytical investigations by others to determine the typical behaviour, including probable failure modes, of reinforced concrete specimens with exposed flexural reinforcement. Based on these findings, two analytical approaches are developed to …

Multiplatform Analysis Seismic Evaluation Of A Non-Seismically Detailed Nonlinear Rc Structure Retrofitted With Magneto-Rheological Dampers, Eric R. Lovejoy

Master's Theses

In prior research, the MR damper's dynamic characteristics are typically modeled in the MATLAB/Simulink environment. Creating a structural model with nonlinear material properties, however, may be challenging in the MATLAB/Simulink environment without approximating the material behavior and neglecting effects such as P-∆ or panel zone behavior. More behaviorally accurate models of these structures can be produced using nonlinear finite element analysis tools such as Abaqus, OpenSees or ZuesNL. These analysis tools, however, are not traditionally used to model the complex nonlinear and controllable behavior of MR dampers, nor their associated control algorithms. One solution is to facilitate communication between these …