Celebrating 20 Years of the ExCEEd Teaching Workshop

In response to the clear need for faculty training, the American Society of Civil Engineers (ASCE) developed and funded Project ExCEEd (Excellence in Civil Engineering Education) which is celebrating its twentieth year of existence. For the past two decades, 38 ExCEEd Teaching Workshops (ETW) have been held at six different universities. The program has 910 graduates from over 267 different U.S. and international colleges and universities. The ExCEEd effort has transformed from one that relied on the grass roots support of its participants to one that is supported and embraced by department heads and deans. This paper summarizes the history of Project ExCEEd, describes the content of the ETW, assesses its effectiveness, highlights changes in the program as a result of the assessment, and outlines the future direction of the program

Assessment of Dynamic Properties of a Crowd Model for Human-Structure Interaction Modeling

Occupants of a structure are thought to behave as a dynamic spring-mass-damper system interacting with the structure through a phenomenon known as human-structure interaction. Understanding this interaction is critical for vibration serviceability as neglecting to account for its effects may result in an overestimation of the dynamic response of a structure, and as a result, a more costly structural design. An experimental study has been performed and the results are compared with analytical models constructed with the parameters proposed by the Joint Working Group (JWG) in the United Kingdom for modeling occupants as a spring-mass-damper system. The results indicate that the parameters of the active and mostly standing crowd model satisfactorily represent the dynamic response of the structure with passive ocaupants standing with bent knees. However, the parameters of the predominantly seated crowd model did not adequately simulate the dynamic response of the structure when passive occupants were seated on the structure. A new set of parameters for passive standing occupants, not specifically addressed by the Joint Working Group, was also assessed yielding acceptable results. This study asserts that at least three different models, with varying parameters, are necessary to thoroughly understand the effects of human-structure interaction. The experimental results confirm the applicability of the JWG parameters for active occupants and verify the appropriateness of previously proposed parameters for modeling the passive standing occupant. (C) 2015 Elsevier Ltd. All rights reserved

Experimental Evaluation of the Influence of Human-Structure Interaction for Vibration Serviceability

The effects of human-structure interaction on the dynamic performance of occupied structures have long been observed. The inclusion of the effects of human-structure interaction is important to ensure that the dynamic response of a structure is not overestimated. Previous observations, both in service and in the laboratory, have yielded results indicating that the effects are dependent on the natural frequency of the structure, the posture of the occupants, and the mass ratio of the occupants to the structure. These results are noteworthy, but are limited in their application,because the data are sparse and are only pertinent to a specific set of characteristics identified in a given study. To examine these characteristics simultaneously and consistently, an experimental test structure was designed with variable properties to replicate a variety of configurations within a controlled setting focusing on the effects of passive occupants. Experimental modal analysis techniques were employed to both the empty and occupied conditions of the structure and the dynamic properties associated with each condition were compared. Results similar to previous investigations were observed, including both an increase and a decrease in natural frequency of the occupied structure with respect to the empty structure, as well as the identification of a second mode of vibration. The damping of the combined system was higher for all configurations. Overall, this study provides a broad data set representing a wide array of configurations. The experimental results of this study were used to assess current recommendations for the dynamic properties of a crowd to analytically predict the effects of human-structure interaction. The experimental results were used to select a set of properties for passive, standing occupants and develop a new model that can more accurately represent the behavior of the human-structure system as experimentally measured in this study

Detection of Internal Defects in Concrete Members Using Global Vibration Characteristics

Rock-pocket and honeycomb defects impair overall stiffness, accelerate aging, reduce service life, and cause structural problems in hardened concrete members. Traditional methods for detecting such deficient volumes involve visual observations or localized nondestructive methods, which are labor-intensive, time-consuming, highly sensitive to test conditions, and require knowledge of and accessibility to defect locations. The authors propose a vibration response-based nondestructive technique that combines experimental and numerical methodologies for use in identifying the location and severity of internal defects of concrete members. The experimental component entails collecting mode shape curvatures from laboratory beam specimens with size-controlled rock pocket and honeycomb defects, and the numerical component entails simulating beam vibration response through a finite element (FE) model parameterized with three defect-identifying variables indicating location (x, coordinate along the beam length) and severity of damage (alpha, stiffness reduction and beta, mass reduction). Defects are detected by comparing the FE model predictions to experimental measurements and inferring the low number of defect-identifying variables. This method is particularly well-suited for rapid and cost-effective quality assurance for precast concrete members and for inspecting concrete members with simple geometric forms

Pharmacokinetics of Ceftiofur Crystalline Free Acid in Male Rhesus Macaques (Macaca mulatta) after Subcutaneous Administration.

Trauma is a common sequela to agonistic social encounters in rhesus macaques (Macaca mulatta), and veterinarians often prescribe antibiotics as part of a balanced treatment plan. Long-acting, single-dose, injectable antibiotics for use in rhesus macaques are unavailable currently. Ceftiofur crystalline free acid (CCFA) is a long-acting, single-dose, injectable third-generation cephalosporin that provides at least 7 d of ceftiofur therapeutic plasma concentrations in swine (Sus scrofa domesticus). We hypothesized that CCFA would achieve similar therapeutic concentrations (≥ 0.2 μg/mL) in rhesus macaques. We describe the pharmacokinetic profile of CCFA in healthy, adult male rhesus macaques ( n = 6) in this 2-period, 2-treatment crossover study of 5 and 20 mg/kg SC administered once. Plasma ceftiofur metabolite concentrations were determined prior to and for a maximum of 21 d after administration. Noncompartmental pharmacokinetic analysis was performed. The 5-mg dose achieved a maximal plasma concentration of 2.24 ± 0.525 μg/mL at 2.59 ± 1.63 h, an AUC of 46.9 ± 17.6 h/μg/mL, and a terminal elimination half-life of 56.5 ± 21.7 h; for the 20-mg/kg dose, these parameters were 9.18 ± 4.90 μg/mL at 1.82 ± 1.30 h, 331 ± 84.4 h/μg/mL, and 69.7 ± 8.86 h, respectively. No adverse effects were noted after either dose. Macaques maintained plasma ceftiofur concentrations of 0.2 μg/mL or greater for at least 2 d after 5 mg/kg SC and at least 7 d after 20 mg/kg SC

The ASCE ExCEEd Teaching Workshop: Assessing 20 Years of Instructional Development

The Excellence in Civil Engineering Education (ExCEEd) Teaching Workshop (ETW), a week-long teacher-training program sponsored by the American Society of Civil Engineers, has been improving the quality of university teaching for twenty years. The 41 workshops conducted over this period have produced 963 graduates from 253 universities around the world. This article celebrates the history of this landmark faculty development initiative. It assesses the extent to which the ETW provides a unique contribution and has influenced teaching practices in U.S. civil engineering programs. This assessment includes participant satisfaction, the long-term influence on participants, the influence on those participants who became ETW faculty leaders, the satisfaction of the deans and department heads who sponsored the participants, the scholarship that has resulted from the ETW, and the implied influence on the engineering students who ultimately benefit from this workshop. Finally, the future direction of the ETW is addressed. Although the workshop is intended primarily for civil engineering programs in the U.S., the results of this study are also highly relevant to other engineering disciplines and to engineering programs outside the U.S

The ASCE ExCEEd Teaching Workshop: Assessing 20 Years of Instructional Development

The Excellence in Civil Engineering Education (ExCEEd) Teaching Workshop (ETW), a week-long teacher-training program sponsored by the American Society of Civil Engineers, has been improving the quality of university teaching for twenty years. The 41 workshops conducted over this period have produced 963 graduates from 253 universities around the world. This article celebrates the history of this landmark faculty development initiative. It assesses the extent to which the ETW provides a unique contribution and has influenced teaching practices in U.S. civil engineering programs. This assessment includes participant satisfaction, the long-term influence on participants, the influence on those participants who became ETW faculty leaders, the satisfaction of the deans and department heads who sponsored the participants, the scholarship that has resulted from the ETW, and the implied influence on the engineering students who ultimately benefit from this workshop. Finally, the future direction of the ETW is addressed. Although the workshop is intended primarily for civil engineering programs in the U.S., the results of this study are also highly relevant to other engineering disciplines and to engineering programs outside the U.S