Conferences, Lectures, & Seminars
Events for February
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Recent development of steel-concrete composite structures and their applications in China
Thu, Feb 01, 2007 @ 02:30 PM - 03:30 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
KAP 203, 2:30pm-3:30pm
February 1, 2007Speaker:
Jianguo Nie, Professor
Tsinghua University
Beijing, ChinaAbstract
Using the combined advantages of both steel and concrete materials, the steel-concrete composite system is a popular type of structure used in both buildings and bridges in China. In this seminar, general information of building and bridge construction in China will be introduced. Then the recent research in new types of connections of steel-concrete composite beams and columns will be presented. Innovative applications of composite system in the repairs/strengthening of bridges and buildings will also be presented.Dr. Jianguo Nie is a Professor of the Department of Civil Engineering, Tsinghua University, China. He is currently holding the title of Cheung Kong Scholar, a high prestigious title awarded by the Chinese Ministry of Education. He is the Director of Research Institute of Structural Engineering at Tsinghua University, and the Director of Key Laboratory of Structural Engineering and Vibration of China Education Ministry, Tsinghua University. Dr. Nie's major research interests are steel-concrete composite structures, strengthening and retrofitting of concrete structures, and applications of steel-concrete composite structures to building and bridge systems. Prof. Nie has more than 20 years of experience in research and directing students in these research areas and has published more than 150 papers and 2 books.Location: Kaprielian Hall (KAP) - 203
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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Introduction to Nanorobotics
Wed, Feb 07, 2007 @ 02:00 PM - 03:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
SPEAKER:
Prof. Aristides Requicha, USC- Gordon Marshall Chair in Engineering and
Professor of Computer ScienceNanorobotics is an emerging field that encompasses: * Programmable assembly of nanoscale components (i) by manipulations with SPMs (or other robotic devices), (ii) by passive self-assembly on programmed templates, or (iii) by active self-assembly of robotic components.
* Design and fabrication of nanorobots with overall dimensions at or below the micrometer range and made of nanoscopic components.
* Programming and coordination of large numbers of such nanorobots. This talk begins with a brief introduction to nanotechnology and then assesses the state of the art and open issues in the three areas above.Location: Kaprielian Hall (KAP) - rielian Hall, Room 203
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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Biodiesel In America - Setting the Stage
Fri, Feb 09, 2007 @ 01:00 PM - 02:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker:Joe Gershen,
Tellurian Biodiesel,
PO Box 3096,
Santa Monica, CA 90408,
310.962.0488Title:
Biodiesel In America - Setting the StageAbstract:For many years energy has been taken for granted, with reliance upon nonrenewable petroleum, natural gas, coal and other fossil-based fuel reserves as a predominant source for transportation, power and home heating needs. Recent market conditions and energy security concerns along with increased environmental and climate change consciousness have created an awareness and demand for non-polluting, domestically produced, renewable resources to supplement our reliance upon petroleum fuels. Our energy future depends on finding sustainable energy solutions, and biodiesel is one of those solutions.The talk will be about the biodiesel marketplace, demand drivers, which include both energy policy and markets, acceptance of biodiesel by manufacturers, as well as opportunities and challenges which face this emerging industry.Location: Kaprielian Hall (KAP) - rielian Hall, 156
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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Behavior of Pile Foundations in Liquefied and Laterally Spreading Ground
Wed, Feb 14, 2007 @ 02:00 PM - 03:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker:
Prof. Scott Brandenberg,
Department of Civil and Environmental Engineering,
UCLAAstract:Structures founded on pile foundations have suffered extensive damage due to earthquake-induced liquefaction and lateral spreading. Damage has been particularly intense when a relatively strong nonliquefied crust layer spreads laterally on top of an underlying liquefiable deposit and exerts large loads on the pile foundations. Lateral spreading hazard poses a large problem for bridges because (1) bridges often cross bodies of water and are founded in a profile consisting of a sloping nonliquefied crust over liquefiable sand, (2) many bridges were constructed before liquefaction and lateral spreading was identified as a hazard to be considered in design, and (3) current design methods have not been sufficiently verified by case histories and model studies. This talk presents a suite of centrifuge studies of pile foundations embedded in a gently sloping profile of nonliquefied clay over liquefiable loose sand over dense sand. The densely instrumented models provide insights into the fundamental mechanisms of load transfer between piles and liquefiable sand, and between pile caps and nonliquefied spreading crusts. The data show how dilatancy (i.e. cyclic mobility) of liquefiable sand affects soil-pile interaction, and how passive loads of laterally spreading crusts are mobilized against pile groups at displacements that are about an order of magnitude larger than observed in tests in nonliquefied soil profiles. Observations from the centrifuge tests led to improved design guidelines for static beam on nonlinear Winkler foundation (BNWF) analyses that are commonly used in design practice. Analyses that utilize the guidelines are shown to reasonably predict pile cap displacements and peak bending moments for cases where the pile groups were laterally stiff to limit damage to the structure. The talk ends with discussion of preliminary results from an ongoing project to develop fragility functions that characterize lateral spreading hazard for approximately 13,000 Caltrans bridges, many of which were not designed to resist lateral spreading loads.Location: Kaprielian Hall (KAP) - rielian Hall 203
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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Changing Project Delivery Strategy......
Thu, Feb 15, 2007 @ 02:30 PM - 04:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
CHANGING PROJECT DELIVERY STRATEGY:
AN IMPLEMENTATION FRAMEWORK
FOR THE TRANSPORTATION PROJECT SECTORSpeaker:
Giovanni C. Migliaccio,
2007 Ph.D. Candidate, University of Texas at Austin,Abstract:
For organizations such as departments of transportation, other public agencies, or private companies, the adoption of a new approach to procure services for delivery of construction projects requires significant organizational changes; these changes include modifications to both their work processes and existing organizational structures. Because these adjustments encompass many different aspects of the organization's interests, they must occur for the change initiative to be successfully implemented. Researchers at the Center for Construction Industry Studies are investigating the adoption of innovative project delivery approaches within the transportation project sector in order to better understand the dynamics of this type of organizational change. This seminar will present findings from a study of state transportation agencies that have recently implemented the design-build method for delivering highway projects.
Using as a case study the new $1.3 billion SH 130 tolled expressway project in central Texas, the research team has analyzed project documentation and performed 39 interviews to individuals affiliated with owner, legal counselor, engineering consultant, and contractor. Findings suggest that project representatives institutionalize practices and routines connected to the new approach by adapting to new challenges, rather than by "overwriting" previously existing practices. Consequently, the institutionalization of innovative approaches to project delivery happens concurrently with a deinstitutionalization of the previous approaches. This concurrency produces different effects on the project environment, depending on the mediating action of some emerging industry practices and the perspectives of the involved parties.
Using these findings, the presenter has developed a conceptual framework for helping owner organizations implement a new project delivery approach. This framework has been further enriched by the data from a comparative study of three transportation projects around the United States. In addition, 90 experts in the implementation of the design-build method for transportation projects were identified and invited to participate in a Delphi study to validate and populate the developed framework. Findings from all of these studies will be presented in this seminar, including preliminary findings from the ongoing Delphi study.
Location: Kaprielian Hall (KAP) - rielian Hall, 203
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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Heavy Metal Stabilization in Contaminated Soil.....
Fri, Feb 16, 2007 @ 01:00 PM - 02:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
HEAVY METAL STABILIZATION IN CONTAMINATED SOIL USING CROSSLINKED BIOPOLYMERS WITH INTERPENETRATING POLYMER NETWORK (IPN) STRUCTURESSpeaker:Shawntine Lai
Environmental Engineer
URS CorporationAbstract:
U.S. Department of Defense has many outdoor small arms firing ranges for weapons training, essential for its mission. Their use, however, generates soil contamination primarily with Pb, which is a characteristic hazardous waste. With common total Pb levels in range soils of 50,000 mg/kg or more, there is an acute need for efficient permanent stabilization technologies. The study proposed the use of biopolymers for Pb stabilization in soils. The concept is based on biopolymers' well-known abilities to bind metals, soil particles and to create the crosslinking networks (interpenetrating polymer networks, IPNs) in the presence of crosslinking agents. Consequently, the soil treatment with crosslinked biopolymer networks able to bind both Pb and soil particles in composites resistant to biodegradation may provide a permanent stabilization. There are several commercialized biopolymers and possible crosslinking agents available, such as guar gum, xanthan gum, chitosan, alginate, etc. Many of them have been widely adapted in soil remediation since they are renewable and cost-effective. They can be used as barriers to prevent the migration of hazardous wastes.The parameters used in this study included biodegradability of the IPNs, weight swelling ratio, and rheological properties of the IPNs. Lead in firing range soil was successfully stabilized up to 99% using crosslinked biopolymers at optimum conditions. The distribution of lead species in soil components was investigated using Selective Sequential Extraction (SSE) procedures, and was altered due to the formation of IPNs. This crosslinked biopolymer technology was also applied to synthetic polluted soil of other metals, such as Cr, Cu, and Fe, and showed remarkable results. This presentation will also provide general information on how to conduct and evaluate Environmental Site Assessments (ESAs) in engineering practice, such as Phase I ESA, Phase II ESA, and Preliminary Endangerment Assessment. The purpose of the ESAs is to identify existing or potential environmental hazards for a subject property. The assessments provide useful information for subsequent remedial action plans.
Location: Kaprielian Hall (KAP) - 156
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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Interface Object Model Framework for Systematic Model-Based Interface Management
Tue, Feb 20, 2007 @ 02:30 PM - 04:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker:
Qian (Victoria) Chen,
Ph.D. Candidate, Dept. of Building Construction, Virginia Tech,Abstract: Various interface issues significantly lower overall project performance and implicitly hinder industrialization of construction. Ignored by traditional project management, interface management (IM) is now regarded by researchers and practitioners as critical to the success of multidisciplinary construction projects. Several challenging problems associated with IM include: 1) how to build a holistic understanding of interface issues in the current built environment for developing all-around IM solutions; 2) how to define and present interface information in a unified, accurate, and efficient way to improve information sharing and implementation among IT applications; and 3) how to resolve interrelated interface issues as a whole to optimize the performance of IM in a project. These problems have neither been well studied nor resolved in the construction management literature. This research is aimed at enhancing overall performance of a project delivery process by improving interface information modeling through systematic model-based interface management. Specifically, this research conducts multi-perspective interface-related analysis to identify comprehensive cause factors for interface issues, and creates an Interface Object Model (IOM) framework that presents the basic data structure and contextual relationships of interface information. This conceptual research also develops a systematic model-based strategy incorporating IOM, project processes, and other IT tools to perform more effective and efficient IM in an integrated project delivery environment.Location: Kaprielian Hall (KAP) - rielian Hall 203
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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Physical Chemical and Toxicological Characteristics of Ultrafine Particulate Matter (PM).....
Wed, Feb 21, 2007 @ 02:00 PM - 03:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Physical, Chemical and Toxicological Characteristics of Ultrafine Particulate Matter (PM): Summary of 6 years Research by the US EPA Southern California Particle Center Speaker:
Prof. Costas Sioutas,
USC- Department of Civil and Environmental EngineeringIncreasing epidemiological and toxicological evidence links cardio-respiratory health effects with exposures to ultrafine particles (diameter < 0.1 µm). Emission inventories suggest that motor vehicles may be primary direct emission sources of ultrafine particles to urban atmospheres. Given the amount of traffic in the Los Angeles Basin, it is important to understand how ultrafine particles behave after emission as they are transported away from busy roadways. Understanding the characteristics of ultrafine particle volatility and how these traffic-emitted ultrafine particles penetrate indoor environments is also vitalThe goals of our research undertaken by the Southern California Particle Center and Supersite were to create an extensive inventory on what is known about the physical and chemical characteristics of atmospheric ultrafine particles. Utilizing a mobile particle concentrator, researchers set about characterizing the physical and chemical PM characteristics and volatility on/near freeways, in source and receptor areas of the Los Angeles Basin, the impact of mobile sources on indoor environments as well as ultrafine PM characteristics and emission factors in roadway tunnels with light-duty or heavy-duty vehicles.The data provided an increased understanding of how physical and chemical characteristics of ultrafine particles change on/near heavily trafficked areas; this information is necessary to better understand exposure outcomes. Relative concentrations of CO, black carbon and particle number decreased exponentially and tracked each other well as one moves away from the freeway. Our studies also showed that particles emitted from vehicles are externally mixed; different particles of the same size can have different chemical compositions. Depending on ambient conditions, between 70-90% of the particles by number, and 10-30% by mass consisted of semi-volatile material originating from condensation of organic vapors from fuel and lube oil. The non-volatile portion is known to primarily consist of elemental carbon, which is often coated with more volatile organic species. The volatility of these particles explains the more rapid decay in their concentration with respect to distance from a roadway, compared to that of non-labile PM species (such as EC) or gaseous co-pollutants such as CO and NOx, the concentration decrease of which would be affected mostly my atmospheric dilution. Our studies also showed that the volatile component of these particles may likely be present in its gaseous phase in indoor environments, causing particle shrinkage and-or compete evaporation as they infiltrate indoors. In future research, given that the majority of people's exposure during commute will be dominated (at least based on particle numbers) to these particles, it would be useful to know whether the non-volatile or semi-volatile material is more toxic.A better understanding of ultrafine particle characteristics and their volatility allows for the narrowing of the search for the most toxic PM components, and would also suggest new emissions control technologies that better protect the public health. Current particle traps remove non-volatile soot particles but not the precursors of the smaller semi-volatile particles. An unintended result of this reduction of the larger, non-volatile particles from the exhaust is the potential increase in the formation/emission of the smaller, semi-volatile PM as seen in our experiments performed at the Caldecott tunnel in which we determined size fractionated emission factors for heavy and light duty vehicles and compared them to those of previous studies in the same location.Location: Kaprielian Hall (KAP) - rielian Hall, 203
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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The Canterbury, New Zealand, Network and CUSP Strong Motion Seismographics
Tue, Feb 27, 2007 @ 03:00 PM - 04:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Speaker:
John B Berrill,
University of Canterbury, and
Canterbury Seismic Instruments Ltd.,
Christchurch, New Zealand
(www.csi.net.nz)Seminar Abstract:Motivated by an expected ~M8 rupture on the Alpine Fault, New Zealand, the engineering seismology group at Canterbury University sought to install a strong-motion network of about 80 instruments in the region. The Canterbury Network (CanNet), now part of the NZ national network, GeoNet, has three main components:
1. A dense array of 15 to 20 instruments to capture details of the rupture mechanism.
2. A network of 40 instruments distributed across the central South Island to record regional attenuation.
3. A local network to study the response of the highly variable 2025 m layer of post-glacial soil beneath the city of Christchurch.
In order to deploy such a number of instruments at affordable cost, the group collaborated with the Electrical Engineering Department of the University to design a low-cost digital accelerograph. The original 12-bit CUSP-3A (CUSP: Canterbury University Seismograph Project) accelerograph, designed to put more points on the map for a fixed budget and low maintenance costs, has been evolved to the 13-bit CUSP-3B and the 17-bit CUSP-3C instrument. Both instruments are web-based for ease of monitoring and down loading of data and, where possible, use off-the-shelf components such as industrial single-board computers and MEMs accelerometers. At this time (February 2007), about half the CanNet instruments have been installed.For the past 15 months, a central-recording system, CUSP-M, developed for monitoring structural response, has been undergoing trials in a building on campus, and will be installed in several structures throughout NZ. It uses the web-based communications of the 3B/C instruments, simple Ethernet wiring to connect up to 32 three-component sensors to the central unit and features digitization at the sensor and synchronized sampling. A hardened version will be employed for the dense, rupure-mechanism array.The speaker is conscious of the isolation of his group on their South Seas islands, and invites your feedback on this program and the instruments.Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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NONLINEAR ANALYSIS OF COMPOSITE AND FUNCTIONALLY GRADED SHELL STRUCTURES
Wed, Feb 28, 2007 @ 10:30 AM - 11:30 AM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
JOINT SEMINAR FOR AME & CIVIL ENGINEERINGSPEAKER: J. N. Reddy,
Advanced Computational Mechanics Laboratory,
Texas A & M University, College Station, TX 77843-3123
jnreddy@tamu.eduABSTRACT
A tensor-based finite element formulation for the nonlinear analysis of laminated shell structures and through-thickness functionally graded shells will be discussed. A tensor-based finite element formulation is used to describe the deformation and 3-D constitutive laws of a shell in a natural and simple way by using curvilinear coordinates. In addition, a family of high-order elements with Lagrangian interpolations is used to avoid membrane and shear locking. A first-order shell theory with seven parameters is derived with exact nonlinear deformations and under the framework of the Lagrangian description. This approach takes into account thickness changes and, therefore, 3D constitutive equations are utilized. Numerical comparisons of the present results with those found in the literature for typical benchmark problems involving isotropic and laminated composite plates and shells as well as functionally graded plates and shells are found to be excellent and show the validity of the developed finite element model. Moreover, the simplicity of this approach makes it attractive for applications in contact mechanics and damage propagation in shells. A number of examples of applications to laminated composite shell structures are presented.Keywords: Finite element model, nonlinear shell theory, multilayered composites, functionally graded shells, numerical examples.Acknowledgement. The research results reported herein were obtained while the authors were supported by the Structural Dynamics Program of the Army Research Office (ARO) through Grant . 45508EG.References
1. R. A. Arciniega and J. N. Reddy, "Tensor-based Finite Element Formulation for Geometrically Nonlinear Analysis of Shell Structures," Computer Methods in Applied Mechanics and Engineering, Vol. 196, Nos. 4-6, pp. 1048-1073, 2007.
2. R. A. Arciniega and J. N. Reddy, "Large deformation analysis of functionally graded shells," International Journal of Solids and Structures, Vol. 44, pp. 2036-2052, 2007.
3. J.N. Reddy, Mechanics of Laminated Composite Plates and Shells: Theory and Analysis, 2nd edition, CRC Press, Boca Raton, Florida, 2004.
Location: Kaprielian Hall (KAP) - RIELLIAN HALL, 203
Audiences: Everyone Is Invited
Contact: Evangeline Reyes
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Earthquake Damage Detection in Two Buildings.....
Wed, Feb 28, 2007 @ 02:00 PM - 03:00 PM
Sonny Astani Department of Civil and Environmental Engineering
Conferences, Lectures, & Seminars
Earthquake Damage Detection in Two Buildings - Comparative Analysis of Several Structural Health Monitoring Methods Including a New Wave MethodSpeaker: Dr. Maria Todorovska,
Department of Civil and Environmental Engineering,
USCAbstract:The only true validation of real time structural health monitoring methods is in terms of sensory data recorded in instrumented structures during a damaging event. For civil structures, damaging events are e.g. earthquakes, explosions, blasts, etc. Due to the high cost of instrumentation and the low frequency of occurrence of such events, data in damaged civil structures are rare, but do exist, e.g. vibrational data recorded in buildings by seismic monitoring arrays during a damaging earthquake. Yet, the existing data are rarely used, and methods are usually tested only on numerically simulated data of response with postulated damage and assumed additive Gaussian noise. Results will be presented of a critical comparative analysis of several structural health monitoring methods applied to detecting damage in two instrumented buildings th the 1971 San Fernando and 1994 Northridge earthquakes, and for which records of 10 other earthquakes are also available.The first method is a new method, based on measuring wave travel times through the building using impulse response functions, applied to structural health monitoring for the first time in the presented work. This method is more reliable than monitoring changes in the apparent building frequencies, which are sensitive to the effects of soil-structure interaction and environmental factors, such as weather. Further, it is local and can detect the location of damage with relatively few sensors as compared to the methods based on detecting changes in curvature of the mode shapes of vibration, which require extensive instrumentation. Another relatively new method is based on detecting novelties in the recorded response using wavelets, previously tested on numerically simulated data but not conclusively on real data. This method is superior to all other methods in its resolution of the estimate of the time of the occurrence of damage. The analysis of this method also revealed that the noise in this method, consisting of high frequency pulses from the ground motion traveling through the building, contains useful information about the travel times through the building, and hence can also be used to infer about the changes of the state of health of the structure. The results by these two methods are compared with the distribution and degree of the observed damage, and with results of analyses based on other indicators of damage, such inter-story (dynamic) drifts estimated from the recorded accelerations, observed changes of the "instantaneous" apparent frequencies of vibration as functions of the amplitudes of response, estimated from the ridges and skeletons of the Gabor transform, and finally by analysis of simulated response using ETABS. The mutual consistency of the results by different analyses methods, and their consistency with the observed damage are discussed and several important conclusions are drawn.Location: KLaprielian Hall 203
Audiences: Everyone Is Invited
Contact: Evangeline Reyes