Rehabilitation and Load Rating of Deteriorated Timber Bridges in Colorado: Parametric Investigations and Implementation

This report presents three major aspects that are related to the evaluation of timber bridges with and without repair: i) laboratory testing, ii) finite element modeling, and iii) load ratings. In addition, worked examples are provided to demonstrate the implementation of research findings. The first part of the report explores the effectiveness of various retrofit techniques in improving the flexural behavior of structural timber. The second part presents the behavior of a timber bridge strengthened with lag bolts, carbon fiber reinforced polymer (CFRP) sheets, and hollow structural sections (HSS). The third part discusses load ratings for timber bridges repaired with HSS. A mechanics-based rating approach is proposed to holistically rate these bridges before and after the repair. The capacity of the girders with the steel beams is as high as 2.56 times that of the control girders. Likewise, the allowable stress of the timber is improved by a factor of 1.39 and 2.09 for flexure and shear, respectively. The effectiveness of the repair becomes pronounced when the deterioration level of the timber girders rises, and the geometric properties of the steel beams are a crucial consideration that alters the rating of the repaired girders. The placement of grouped steel beams is recommended to raise the efficacy of the repair system

Development of Tub Girders for Prestressed Concrete Bridges Complying With LRFD

This report presents the development of tub girders for prestressed concrete bridges complying with the Load and Resistance Factor Design (LRFD) method. In addition, the use of 0.7 in. strands is elaborated for the B618-U girders of the Colorado Department of Transportation. In the first part of the report as regards a state-of-the-art review, technical parameters are categorized in accordance with physical characteristics and corresponding contents are examined. The second part of the report suggests a new tub girder series. After understanding the performance of tub girders selected from six transportation agencies in the nation, an optimization algorithm is employed to generate efficient prototype sections. Afterward, detailed investigations are conducted to appraise various practical aspects. A simplified version of the prototype sections is also delineated for regional precasters. A comparative study is carried out to evaluate the geometric stability and production costs of the prototype, simplified, and existing B618-U girders. Implementation: A new tub girder series is proposed to improve structural efficiency and the potential implementation of 0.7 in. strands is discussed for bridge construction in Colorado

AGENDA: Drawing the Blueprint for a Sustainable Natural Gas Future

A stakeholder-led forum discussing the key topics affecting natural gas as a safe and sustainable energy resource. Participants learned about the current research and related resources at Colorado’s three research universities and participated in designing future research needs

AGENDA: Water, Oil and Gas: Nuts and Bolts of Oil and Gas Leases, Surface Use Agreements, and Water Rights for Non-Oil and Gas Attorneys

This third program in the Water, Oil, and Gas 101 series was designed to provide those who don’t practice in the area with essential information regarding leases, surface use agreements, siting considerations for oil and gas facilities, the resolution of disputes before the Colorado Oil and Gas Conservation Commission (COGCC), the ins and outs of nontributary and produced nontributary ground water, and water rights as an asset. Program topics include: Oil and Gas Leases Surface Use Agreements (SUAs) Government’s Role in Authorizing Locations for Oil and Gas Development Technical Aspects of Nontributary and Produced Nontributary Ground Water Produced Nontributary Ground Water from the Perspective of Industry Nontributary Ground Water as a Landowner Asse

AGENDA: Water, Oil and Gas: Nuts and Bolts of Oil and Gas Leases, Surface Use Agreements, and Water Rights for Non-Oil and Gas Attorneys

This third program in the Water, Oil, and Gas 101 series was designed to provide those who don’t practice in the area with essential information regarding leases, surface use agreements, siting considerations for oil and gas facilities, the resolution of disputes before the Colorado Oil and Gas Conservation Commission (COGCC), the ins and outs of nontributary and produced nontributary ground water, and water rights as an asset. Program topics include: Oil and Gas Leases Surface Use Agreements (SUAs) Government’s Role in Authorizing Locations for Oil and Gas Development Technical Aspects of Nontributary and Produced Nontributary Ground Water Produced Nontributary Ground Water from the Perspective of Industry Nontributary Ground Water as a Landowner Asse

Data-Driven Bridge Management Using Descriptive and Predictive Machine Learning Models

Bridges deteriorate with time and use. To monitor deterioration of the bridges, several US Acts mandate the state and local governmental agencies (including cities, state transportation agencies, etc.) to perform regular bridge inspections. The aforementioned inspections across the nation, which have been conducted since 1970\u2019s (including our region), have generated valuable historic databases of bridge data based in local and state governmental agencies. While these agencies currently use these inspections to prevent failure and to administrate the national bridge network by setting priorities and establishing criteria to allocate available resources to the structures in most critical conditions, we believe these databases are heavily underutilized. In particular, with the advent of machine learning and data mining methods, we envision data-driven solutions that can derive much more valued hidden knowledge that can be utilized for enhanced bridge management. While in the past, various data-driven deterioration models are proposed in the literature to model bridge deterioration, these models either suffer from low accuracy or are too complex to be applicable. Recently deep learning is shown to significantly outperform other analytical modeling methodologies in a variety of application domains. In this study, we present new deep learning models for enhanced bridge management. In particular, we focus on the two problems of bridge subtyping (descriptive analysis) and bridge deterioration forecasting (predictive analysis). Through empirical evaluation with real data, we demonstrate that our solutions for these problems significantly enhance the state-of-the-art in bridge management

Feeling Close: Emotional Intensity Reduces Perceived Psychological Distance

The results of 6 experiments indicate that emotional intensity reduces perceived psychological distance. People who described events emotionally rather than neutrally perceived those events as less psychologically distant, including embarrassing autobiographical events (Experiment 1), past and future dentist visits (Experiment 2), positive and negative events (Experiment 3), and a national tragedy (Experiment 6). People also perceived an event (dancing in front of an audience) as less psychologically distant when they were in a more emotionally arousing social role (of performer) than in a less emotionally arousing social role (of observer; Experiment 4). Two findings bolster the causal role of emotional intensity in reducing perceived psychological distance. First, reported emotional intensity was negatively correlated with perceived psychological distance and statistically mediated the effect of being in an emotionally arousing social role on perceived psychological distance (Experiment 4). Second, providing people with an alternative interpretation of their emotions (emotionally ambiguous whale songs) significantly reduced, even reversed, the negative correlation between self-reported emotional intensity and perceived psychological distance (Experiment 5). These findings about emotional intensity are consistent with the broader idea that perceived psychological distance is grounded in and influenced by the phenomenology of objective distance. Implications for theories of psychological distance, emotionality, and choice are discussed

AGENDA: Water, Oil and Gas 101

Program co-chairs: Sarah Klahn, Matthew Sura; planning committee: Susan Daggett, Kathryn Mutz. This full-day program, cosponsored by the Rocky Mountain Land Use Institute (Sturm College of Law, University of Denver), the Colorado Bar Association CLE, and White & Jankowski, LLP, was the first of a 3-part series focusing on water, oil and gas issues of critical interest in Colorado. The first program provided an overview of the pertinent law and issues generated when the water, oil and gas industries interact; and addressed water quality concerns and the purchasing of water from municipalities for hydraulic fracturing and drilling. Program #2 is scheduled for June 11; Program #3 for August 16