Bridges Structural Health Monitoring and Deterioration Detection Synthesis of Knowledge and Technology

INE/AUTC 10.0

New chemical engineering provision: Quality in diversity

Recent growth in chemical engineering student numbers has driven an increase in the number of UK universities offering the subject. The implications of this growth are described, along with the different challenges facing new providers in the UK compared with established departments. The approaches taken by the various new entrants are reviewed, with reference to recruitment strategies, infrastructure, the use of external facilities, and the particular flavours of chemical engineering being offered by the new providers. Information about the differentiating features of the large number of chemical engineering degree courses now available is somewhat indistinct: this should be rectified in the interests both of prospective students and of employers. Dilemmas facing new providers include the need to address the fundamentals of the subject as well as moving into more novel research-led areas; enabling students to develop the competencies to sustain them for a whole career as well as meeting immediate employer needs; and providing sufficient industry understanding when academics may lack substantial industrial experience. The central importance of practical provision and of the design project, and the approaches taken by new providers to deliver these components, are reviewed, together with the role of software tools in chemical engineering education, and measures to facilitate industry input into courses. As long as it is not used prescriptively or to inhibit innovation, the accreditation process provides constructive guidance and leverage for universities developing new chemical engineering programmes

Study of UHPC reinforced by graphene oxide & carbon nanotubes composites and steel fibers

Ultra High Performance Concrete is a high strength material, where different admixtures are included to improve its performance. Some of the newest admixtures are graphene oxide and carbon nanotubes. However, little is known about their dosage and mechanical structure. The objective of this TFM is to do a literature review of the state of the art, test different dosages on compression tests, obtain the constitutive equation and curve of the material and create a simple FEM to check the consistency of the equation

Retrofitting of Bridge Elements Subjected to Predominantly Axial Load Using UHPC Shell

In the United States, ~30% of the ~600,000 highway bridges are categorized as structurally deficient or functionally obsolete. These bridges should be replaced or upgraded to sustain the transportation needs of the growing public and private sectors of the U.S. economy. It is not uncommon for structures to have advanced levels of corrosion-induced damage where major repair and maintenance works are required. However, the transportation infrastructure may undergo disruption during rehabilitation causing interruption to critical economic public, civil and commercial activities. This mandates the development of new techniques and materials for accelerated rehabilitation and resilience. To address this issue, a repair method has been developed at Florida International University (FIU), using Ultra High-Performance Concrete (UHPC) for members under axial load. This research investigates the mechanical and durability performance of the proposed retrofit method through experimental and numerical studies. The properties of UHPC, such as high compressive and tensile strength, workability, and impermeability make it a suitable choice as a repair material for retrofitting the damaged body of the marine vii piles, and application of UHPC could provide an efficient solution to address the pressing issue of bridge rehabilitation. This research firstly aims to investigate the mechanical performance of UHPC repair for damaged bridge columns. To achieve this goal, an experimental study was designed to evaluate the mechanical performance of the repaired columns under a combination of static axial and cyclic lateral loads (to simulate operational conditions). Moreover, the extent of macrocell development between the dissimilar concrete materials was monitored to identify the possible beneficial properties of UHPC related to corrosion. Conclusions and recommendations for capacity restoration and corrosion protection are made based on the results which can be used in evaluating the suitability of UHPC as a strengthening compound in concrete structures for any given application

Integration + Innovation: Proceedings of the 2019 Building Technology Educators\u27 Society Conference

This volume contains papers, abstracts, and posters from the 2019 Building Technology Educators\u27 Society (BTES) Conference, which focused on Integration and Innovation as the theme. Innovation can begin with conjecture, with a searching for more effective solutions, or with an application to currently unknown or unarticulated needs. Innovation scholarship examines the personal intellectual habits that support new ideas, such as openness and exploratory behavior, as well as the circumstances behind the places in which creativity flourishes, such as support for cross-disciplinary fertilization and access to resources. The 2019 BTES conference explored the role of technology education and curriculum in cultivating these intellectual habits in our students (and ourselves) and in creating the organizational spaces in which the future of practice will be shaped. Sessions shared exemplary proposals of research and pedagogical applications that explore innovative practices and integrative thinking in the academy and profession

Wireless Sensing System for Load Testing and Rating of Highway Bridges

Structural capacity evaluation of bridges is an increasingly important topic in the effort to deal with the deteriorating infrastructure. Most bridges are evaluated through subjective visual inspection and conservative theoretical rating. Diagnostic load test has been recognized as an effective method to accurately assess the carrying capacity of bridges. Traditional wired sensors and data acquisition (DAQ) systems suffer drawbacks of being labor intensive, high cost, and time consumption in installation and maintenance. For those reasons, very few load tests have been conducted on bridges.;This study aims at developing a low-cost wireless bridge load testing & rating system that can be rapidly deployed on bridges for structural evaluation and load rating. Commercially available wireless hardware is integrated with traditional analogue sensors and the appropriate rating software is developed. The wireless DAQ system can work with traditional strain gages, accelerometers as well as other voltage producing sensors. A wireless truck position indicator (WVPI) is developed and used for measuring the truck position during load testing. The software is capable of calculating the theoretical rating factors based on AASHTO Load Resistance Factor Rating (LRFR) codes, and automatically produces the adjustment factor through load testing data. A simplified finite element model was used to calculate deflection & moment distribution factors in order to reduce the amount of instrumentation used in field tests. The system was used to evaluate the structural capacity of Evansville Bridge in Preston County, WV. The results show that the wireless bridge load testing & rating system can effectively be implemented to evaluate the real capacity of bridges with remarkable advantages: low-cost, fast deployment and smaller crew

Investigation and development of a flexible gripper with adaptable finger geometry

Das zuverlässige und schonende Greifen ist ein Hauptanliegen bei der Entwicklung von neuartigen Greifvorrichtungen. Je größer die Kontaktfläche zwischen dem Greifer und dem Greifobjekt ist, desto schonender und zuverlässiger ist der Greifvorgang. Um dieses Ziel zu erreichen wurden in den letzten Jahrzehnten zahlreiche Untersuchungen zu adaptiven passiven Greifern durchgeführt. Ein neuer Forschungszweig im Bereich selbstadaptiver Greifer sind Greifer mit nachgiebigen blattfederartigen Greifelementen (Greiferfinger) Die Funktionsweise basiert auf dem elastischen Ausknicken der Greifelemente infolge einer translatorische Antriebsbewegung Die vorliegende Arbeit konzentriert sich auf die Verbesserung des Greifvorgangs, indem die Kontaktlänge zwischen den blattfederartigen Greiferfingern und dem zu greifenden Objekt deutlich erhöht wird. Um diese Aufgabenstellung zu lösen, muss eine geeignete Greifergeometrie für ein gegebenes Greifobjekt berechnet werden. Die gezielte Berechnung der erfoderlichen Greifergeometrie für ein bekanntes Greifobjekt ist nicht möglich. Daher wurde als Lösungsansatz die umkehrte Richtung gewählt. Für eine definierte Greifgeometrie wird die Gestalt des dazu passenden “idealen” Greifobjektes ermittelt und anschließend mit der Gestalt zu greifenden Objektes verglichen. Bei Gestaltabweichungen wird die Greifergeometrie iterative verändert, bis seine geeignete Greifergeometrie gefunden wurde. Im Rahmen der vorliegenden Arbeit wird zunächst die Ermittlung des “idealen” Greifobjektes behandelt. Es wurde ein Algorithmus entwickelt, der für eine vorgegebene Greifergeometrie die Gestalt eines runden bzw. elliptischen Objektes ermittelt. Der Algorithmus verwendet als Eingabedaten die Biegelinien der elastisch ausgeknickten Greiffinger unter Berücksichtigung unterschiedlicher Randbedingungen. Als Ausgabedaten liefert der Algorithmus die Gestalt des passenden Greifobjektes zurück. Für quadratische bzw. rechteckige sowie für dreieckige Objekte wurden unterschiedliche Greifgeometrien untersucht. Außerdem wird für quadratische und rechteckige Objekte das Lösungskonzept für die Entwicklung eines weiteren Algorithmus beschrieben. In Kapitel 1 wird eine Klassifizierung von Greifern basierend auf der Anpassungsfähigkeit vorgestellt. In Kapitel 2 werden Lösungskonzepte, Modelle und Theorien vorgestellt. In Kapitel 3 werden Ablaufdiagramme der Algorithmen dargestellt. In Kapitel 4 wird die Entwicklung des Algorithmus für elliptische Objekte und deren Betriebsmodi beschrieben. In Kapitel 5 werden Greifgeometrien für quadratische bzw. Rechteckige sowie für dreieckige Objekte analysiert und die Ideen eines Algorithmus für quadratisch bzw. rechteckige Objekte beschrieben. In Kapitel 6 wird ein kurzer Überblick über die zukünftige Arbeiten.Reliable and gentle gripping is a major concern in the development of new gripping devices. The larger contact surface between the gripper and the gripping object, the gentler and more reliable the gripping process. In order to achieve this goal, further investigations on adaptive passive grippers have been carried out in the recent decades. A new branch of research in the field of self-adaptive grippers are compliant leaf-spring-like gripping elements (gripper fingers). Its mode of operation is based on the elastic buckling of the gripping elements as a result of a translatory drive movement. The present work focuses on improving the gripping process by increasing significantly the contact length between the compliant leaf-spring-like gripper fingers and the object to be gripped. In order to solve this task, a suitable gripper geometry for a given gripping object should be calculated The specific calculation of the required gripper geometry for a known gripping object is not possible; therefore, this work aims in the opposite direction. For a defined gripping geometry, the shape of the matching “ideal” gripping object is determined and then compared with the desired object to be gripped. In case of a deviation in the size, the gripper geometry is iteratively changed until its suitable gripper geometry has been found. In the present work, the determination of the “ideal” gripping object is the first task to deal with. An algorithm has been developed to determine the shape of a round-elliptical object for a given gripper geometry. The algorithm uses as data input the bend lines of the compliant twogripper finger under different boundary conditions. As data output, the algorithm returns the shape of the matching gripping object. For square-rectangular and triangular objects, different gripping geometries have been investigated. Furthermore, for square-rectangular objects, solution concepts for the development of an algorithm is described. In chapter 1, a classification based on adaptability is presented. In chapter 2, solution concepts, models and theories involved are introduced. In chapter 3, process flow diagrams of the algorithms are presented. In chapter 4, the development of the algorithm for elliptical objects and its operation modes are described. In chapter 5, gripping geometries for square-rectangular and triangular objects are analysed and the ideas of an algorithm for square-rectangular objects are described. In chapter 6, a brief overview of the futur work is commented.Tesi

Engineering handbook

1998 handbook for the faculty of Engineerin

Engineering handbook

1998 handbook for the faculty of Engineerin