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This paper addresses the critical knowledge gap in the structural performance of porcelain insulators in overhead railway power systems through experimental evaluations. The focus is on porcelain insulators as part of a contact wire registration assembly (CWRA) in the railway power system. While porcelain insulators are the most widely used high-voltage insulator material, no previous studies have investigated the impact of age on their ultimate load capacity in overhead rail systems. The paper presents the experimental design for tension and a novel 45-degree test setup that replicates field conditions, as well as an overview of the test specimens, which were both new and retired from the field. The results indicate that aging has no impact on the strength of insulators in direct tension tests, but retired insulators in the CWRA show a reduced capacity. Additionally, the location of the drop bracket has a notable influence on the failure mode and stiffness of the assembly. The findings contribute to future improvements in system design and performance. Future research should include material testing, finite element studies, and dynamic testing of the full CWRA setup to further understand insulator performance and support resilient power transmission and distribution systems. Additionally, similar tests should be conducted on polymeric insulators, due to their prevalence. [ABSTRACT FROM AUTHOR]

Concrete-filled fiber-reinforced polymer (FRP) tubes (CFFTs) offer an alternative to traditional reinforced concrete columns for new construction applications due to their high strength, ductility, and corrosion resistance properties. Despite their popularity, there is a lack of accurate analytical models for the cyclic/seismic performance of CFFT columns. This is due to the absence of precise stress–strain models for FRP tubes and confined concrete under cyclic loading. Previous experiments on CFFT columns suggest that even minimal reinforcement (≤1%) provides essential energy dissipation for extreme events. However, existing stress–strain models for FRP-confined concrete often neglect the contribution of longitudinal and transverse steel reinforcement. While some researchers have proposed material models to address this issue, the analytical modeling of confinement effects from both steel reinforcement and FRP tubes, especially under lateral cyclic loading, continues to pose a significant challenge. This study aims to use previously collected experimental data to evaluate current analytical modeling approaches in OpenSeesPy3.5.1.12 to simulate the lateral cyclic behavior of CFFT columns with ±55° glass fiber-reinforced polymer (GFRP) fiber orientation. Both the lumped inelasticity and the distributed inelasticity modeling approaches are applied. The performance of various FRP confinement models is compared. The effect of plastic hinge length is also considered in the lumped plasticity approach. The findings suggest that integrating a fiber element section into the plastic hinge zone enhances the efficiency of the distributed inelasticity approach. This method accurately captures the non-linear behavior in the critical region and precisely predicts the shape of the hysteretic curve, all while reducing computational costs. Conversely, the lumped inelasticity modeling approach effectively forecasts energy dissipation and peak load values across the entire cyclic hysteresis curve, offering significant computational savings. Finally, a generalized modeling methodology for predicting the response of CFFTs under cyclic lateral load is proposed and subsequently validated using experimental results found in the existing literature. [ABSTRACT FROM AUTHOR]

Recent studies have suggested a link between attention deficit hyperactivity disorder (ADHD) and increased creativity and ingenuity. Clinical work suggests that individuals with ADHD generally gravitate toward exploratory rather than exploitative thinking. Yet, these theories have not been tested in the field. This paper is a case study of a transformative undergraduate summer research program that allows engineering students with ADHD to spend 10 weeks in engineering labs at a research-intensive (R1) university. The program intends to show that students with ADHD can excel in engineering and STEM fields when placed in research environments that align with their natural cognitive processes and preferences. Using an interpretative phenomenological analysis (IPA) on post-program participant interviews, this paper suggests that engineering students with ADHD perceive that they learn more effectively when given the opportunity to explore academic material via hands-on research. The traditional structure of STEM education, with its focus on lectures and rigid curricula, causes significant harm to these students, leading to struggles, anxiety, and even thoughts of dropping out. In contrast, the research environment appears to foster creativity and motivation in students with ADHD, as it allows for exploration, provides real-world problem-solving opportunities, and offers tangible, hands-on experiences. This paper highlights the need for a paradigm shift in engineering pedagogy to better engage with and retain this neurodiverse student population and fully harness their creative potential. [ABSTRACT FROM AUTHOR]

In modern transportation projects, the demand for skewed bridges is increasing. Restrictive site constraints, particularly in urban infrastructure projects, yield severely skewed bridges that demand specific design and construction considerations. In particular, the acute corners have reinforcement details that are challenging to construct and often perform poorly. Although the Federal Highway Administration has recognized this problem, to date a simplified detail has not been suggested and evaluated. To tackle this challenge, the Connecticut Department of Transportation partnered with the University of Connecticut to propose a simplified reinforcement detail for acute corners that replaces the normal transverse reinforcement with reinforcement placed along the skew with specific detailing to avoid congestion. An analytical study was conducted using CSiBridge to evaluate the performance of the detail with different skew angles. A series of pushover analyses were performed to capture the flexural yielding of the parapet and measure the stresses in the reinforcing bars in the slab. Based on these findings, a simplified detail for the acute corner of skewed bridge decks is provided. [ABSTRACT FROM AUTHOR]