Conferences, Lectures, & Seminars
Events for September
-
Astani CEE Department Seminar
Wed, Sep 14, 2011 @ 01:00 PM - 02:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker: Chimay J. Anumba, Professor and Head, Department of Architectural Engineering, The Pennsylvania State University
Talk Title: A Holistic Approach to Energy Efficient Building Systems: the DOE Innovation Hub
Abstract: Buildings are known to account for about 40% of the energy use in most industrialized countries and it is estimated that people spend 80â90% of their time in buildings -residences, offices, factories, schools, places of worship, public amenities, recreational facilities, etc. This makes it important that energy use in buildings is considered an important component of efforts geared towards addressing the worldâs energy crisis. This presentation will argue that solutions that focus solely on supply-side aspects of the energy problem need to be complemented by demand-side efficiency initiatives. It will discuss the holistic approach being adopted in the new US Department of Energy-funded $129m innovation hub for energy efficient buildings, which is led by the Department of Architectural Engineering at Penn State University. The key tasks being undertaken as part of the project will be described as well as their broader implications. Particular attention will be paid to the role of IT and integrated project delivery strategies in achieving the objectives of the innovation hub.
Biography: Chimay Anumba holds a Ph.D. in Civil Engineering from the University of Leeds, UK; a higher doctorate â D.Sc. (Doctor of Science) - from Loughborough University, UK; and an Honorary Doctorate (Dr.h.c.) from Delft University of Technology in The Netherlands for outstanding scientific contributions to Building and Construction Engineering. His research interests are in the fields of advanced engineering informatics, concurrent engineering, knowledge management, distributed collaboration systems, and intelligent systems. He has over 450 scientific publications in these fields and his work has received support worth over $150m from a variety of sources. He has also supervised to completion more than 37 doctoral candidates and 18 postdoctoral researchers. He is a Professional Engineer and Fellow of the ASCE, ICE, IStructE, and CIOB.
Host: Dr. Burcin Becerik
Location: Kaprielian Hall (KAP) - 209
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
-
Astani CEE Department Seminar
Wed, Sep 14, 2011 @ 11:00 PM - 12:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker: Chimay J. Anumba, Professor and Head, Department of Architectural Engineering, The Pennsylvania State University
Talk Title: A Holistic Approach to Energy Efficient Building Systems: the DOE Innovation Hub
Abstract:
Buildings are known to account for about 40% of the energy use in most industrialized countries and it is estimated that people spend 80â90% of their time in buildings -residences, offices, factories, schools, places of worship, public amenities, recreational facilities, etc. This makes it important that energy use in buildings is considered an important component of efforts geared towards addressing the worldâs energy crisis. This presentation will argue that solutions that focus solely on supply-side aspects of the energy problem need to be complemented by demand-side efficiency initiatives. It will discuss the holistic approach being adopted in the new US Department of Energy-funded $129m innovation hub for energy efficient buildings, which is led by the Department of Architectural Engineering at Penn State University. The key tasks being undertaken as part of the project will be described as well as their broader implications. Particular attention will be paid to the role of IT and integrated project delivery strategies in achieving the objectives of the innovation hub.
Biography:
Chimay Anumba holds a Ph.D. in Civil Engineering from the University of Leeds, UK; a higher doctorate â D.Sc. (Doctor of Science) - from Loughborough University, UK; and an Honorary Doctorate (Dr.h.c.) from Delft University of Technology in The Netherlands for outstanding scientific contributions to Building and Construction Engineering. His research interests are in the fields of advanced engineering informatics, concurrent engineering, knowledge management, distributed collaboration systems, and intelligent systems. He has over 450 scientific publications in these fields and his work has received support worth over $150m from a variety of sources. He has also supervised to completion more than 37 doctoral candidates and 18 postdoctoral researchers. He is a Professional Engineer and Fellow of the ASCE, ICE, IStructE, and CIOB.
Location: Kaprielian Hall (KAP) - 209
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
-
Astani CEE Department Seminar: The problem of dynamic fracture in brittle materials and its peridynamic solution
Mon, Sep 26, 2011 @ 01:00 PM - 02:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker: Dr. Florin Bobaru, Mechanical and Materials Engineering, University of Nebraska-Lincoln
Abstract: Dynamic fracture in nominally brittle materials (in which plastic work is minimal) has significant technological relevance in, for example, designing material systems resistant to impact damage and penetration, cracking of pavement and infrastructure under shock loadings, hydraulic fracturing for enhanced extraction of oil and gas, mining operations, safety of long-term storage of spent nuclear fuel through vitrification, etc. Experiments on dynamic brittle fracture in amorphous materials exhibit a large variety of complex phenomena, including: crack branching, crack-path instabilities, successive branching events, secondary cracking. Modeling and simulation of dynamic fracture in brittle materials has been one of the most challenging problems in computational mechanics. In spite of significant efforts dedicated to this phenomenon over the past several decades (using cohesive-zone models, molecular dynamics methods, etc) fundamental issues and discrepancies between simulation results and experimental observations have remained unsolved.
In this talk I will present peridynamic (nonlocal) models for dynamic brittle fracture. I will show that peridynamics correctly reproduces many of important features of dynamic crack propagation. In particular, the crack propagation speed and the crack path obtained with peridynamics approach experimental values. We use the peridynamic model to also investigate the influence of the stress waves on the crack branching angle and the velocity profile of a propagating crack in a branching event. We observe that crack branching in peridynamics evolves as described by the phenomenology deduced from the experimental evidence: when a crack reaches a critical stage it splits into two or more branches, each propagating with the same speed as the parent crack, but with a much reduced process zone. The results confirm the recent belief that dynamic fracture in brittle materials happens through an evolution of micro-damage and micro-cracking, and is controlled by the âinner problemâ taking place in the process zone rather than by the âouter problemâ that classical fracture mechanics solves.
Biography: Education and employment history:
⢠B.S. (1995) Mathematics and Mechanics, University of Bucharest, Romania
⢠M.S. (1995) Mathematics and Mechanics of Solids, University of Bucharest, Romania
⢠Ph.D. (2001) Theoretical and Applied Mechanics, Cornell University, Ithaca, NY Associate Professor, Mechanical and Materials Engineering at University of Nebraska-Lincoln (since 2007). Assistant Professor of Engineering Mechanics, UNL (2001-2007). Visiting positions: Summer Research Fellow (2002 â 2004, 2005) at Sandia National Laboratories; Visiting Scholar (Sept.-Dec. 2008), The Fracture Group, Cavendish Lab, University of Cambridge, Cambridge, U.K.; Visiting Scholar (Jan.-Mar. 2009), Multiscale Dynamic Material Modeling Department, Sandia National Laboratories; Visiting Associate Professor (Apr.-Aug. 2011), Mechanical and Civil Engineering, California Institute of Technology, Pasadena, California.
Host: Dr. Jean-Pierre Bardet
Location: Kaprielian Hall (KAP) - 209 Conference Room
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
-
Oral Dissertation Defense
Wed, Sep 28, 2011 @ 10:00 AM - 12:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker: Arash Noshadravan, CEE Ph.D. Candidate
Talk Title: Stochastic Characterization, Realization and Upscaling of Polycrystalline Materials
Abstract: Almost all metallic structures, in particular aerospace systems, consist of polycrystalline materials. There is an inherent heterogeneity in the structure of polycrystals that results from variation in the morphology and texture of underlying microstructures, characterized by geometrical shape, size and crystallographic orientations. The prediction of scatter in mechanical behavior of metallic systems due to these microstructural heterogeneities is of significant importance to many engineering applications. The inherent heterogeneity can be adequately described by a probabilistic approach. Stochastic representation of material properties can also accommodate uncertainty stemming from incomplete data and missing information.
This dissertation is motivated by two challenges involved in developing a probabilistic framework for characterization, realization and upscaling of polycrystalline materials. The first one is concerned with the construction of a sufficiently representative description of random media in terms of morphology and material properties, for an intended purpose. The second important challenge arises in modeling the relationship between the random micro-heterogeneities and the parameters or functions used to describe the physical processes of interest at the coarse scale. One of the essential questions in this regard is whether the coarse scale description is capable of capturing the signature of fine scale characteristics. The inherent heterogeneities in the nature of these fine scale features are reflected on coarse scale observables in the form of random fluctuations around the average response. Hence, any mechanistic model must account for these fluctuations in order to capture the effect of subscale heterogeneities. To address these challenges, we first introduce a statistical characterization of an experimental database on morphology and crystallography. The resulting statistical model is used as a surrogate to further experimental data, required for calibration and validation. We then discuss the construction of a stochastic mechanistic model for mesoscale description of materials with microstructure. The linear elastic constitutive matrix of this model is described mathematically as a random matrix which is bounded from above and below. The identification of model parameters using statistical ensembles of digitally generated random microstructures is presented. We validate the predictive accuracy of the probabilistic model using simulated data resulting from subscale simulations. Also discussed in this work is a simple application problem in order to investigate the capability of the model to detect the signature of mesoscale damages. Finally, we study the effect of heterogeneities on the stochastic wave response of random polycrystalline microstructures making use of the microstructure simulation tool developed in the first part of this work.
Location: Kaprielian Hall (KAP) - 209 Conference Room
Audiences: Everyone Is Invited
Contact: Evangeline Reyes