Advanced Technology for Large Structural Systems
[an NSF Graduated Center]
Lehigh University’s Advanced Technology for Large Structural Systems (ATLSS) Engineering Research Center, under the direction of Joseph T. Stuart Professor of Structural Engineering Richard Sause, Ph.D., P.E, is a national center for research and education on structures and materials of the infrastructure. Established in May 1986 under the direction of emeritus faculty John W. Fisher, Ph.D., P.E., with a grant as part of the National Science Foundation’s (NSF) Engineering Research Center (ERC) program, the Center now addresses the research goals of the NSF, the United States Department of Transportation, the United States Department of Defense, the Commonwealth of Pennsylvania, and numerous additional national, state, and local industry and government organizations and agencies. Significant research has been performed to develop data on fatigue resistance, fracture resistance, strength evaluation of various components and configurations, proof testing, design verification, high performance materials, and product evaluation for a wide variety of transportation structures.
Sponsored Research Program
The ATLSS sponsored research program supports the University’s position that “the researcher’s sense of continual discovery and our cultivation of the theory-to-practice continuum shape all that we do at Lehigh”. Funding for ATLSS’s sponsored research programs is obtained through both the public and private sector. ATLSS faculty and research staff are continually exploring sponsored research programs that support the intellectual focus of the Center, which currently includes areas such as Advanced Structural Materials and Systems, Infrastructure Deterioration, Infrastructure Hazard Mitigation, Infrastructure Reliability, Maintenance, and Life Cycle Management, Intelligent Infrastructure, and Simulation, Measurement, and Evaluation.
Examples of Recent Testing Projects
Note: The following represents a partial list of projects only.
Airport taxi deck fatigue tests
Beam-column seismic tests
Bridge bearing compression and friction tests
Bridge orthotropic deck fatigue tests
Bridge main cable wire tests
Calibrations – high capacity compression and tension load cells
Calibrations – high capacity hydraulic rams
Calibrations – portable truck scales
Carbon fiber tube tension and compression tests
Composite liner panel compression tests
Composite panel flexure and fatigue tests
Composite piling flexural and compression tests
Compressor rotor assembly tension tests
Concrete anchor embedment pullout tests
Concrete column compression tests
Concrete girder flexure and shear tests
Concrete lintel beam flexure tests
Concrete panel flexure tests
Corrugated girder compression and flexure tests
Electrical transmission line tower tests
Escalator step fatigue tests
FAA structures impact tests
Fabric and wire sling tension tests
FRP bridge deck flexure tests
H-pile weld splice flexure tests
Helicopter cabin lift cradle proof tests
Marine fender performance tests
Modular expansion joint fatigue tests
Monorail girder fatigue test
Nuclear reactor closure head lift rig
Nuclear reactor coolant pump and containment lifting beam proof tests
Nuclear reactor crane and lifting components proof tests
Nuclear reactor low profile transporter
Nuclear spent fuel canister proof tests
Parking garage crash rail test
Railroad rail flexural and fatigue tests
Rebar couplers tension tests
Roller assemblies compression and friction tests
Roof joist loading tests
Scaffold assemblies and components
Ship structure evaluation tests
Shoring posts and assemblies
Structural strand tension tests
Suspender rope tension and fatigue tests
Suspender rope wire tests
Timber mat flexure tests
Tool cabinet raking and compression tests
Vehicle bumper assembly
Wind fairing impact tests
Wooden table top capacity tests
ATLSS Infrastructure Monitoring Program
Lehigh University’s ATLSS Infrastructure Monitoring (AIM) program is internationally recognized as a leader in the field testing and evaluation of bridges and related structures and continues to advance the state of the art in this field. Although the University’s structural engineering faculty, mainly under the direction of emeritus faculty Dr. John W. Fisher and Dr. Ben T. Yen, had performed countless field instrumentation projects on bridges and other transportation structures over the previous three decades, it was during the late 1990s that researchers at the ATLSS Engineering Research Center realized that the owners of various transportation systems had more definitive needs, both research and task oriented. In 2000, the operations of the Center’s AIM program formally began.
Over the past eleven years, the AIM program’s faculty and research staff have conducted or been involved with field evaluations and failure analysis of major bridge structures and other infrastructure systems throughout the United States. Bridge owners have sought technical support for projects that included load testing and long-term monitoring of a variety of bridge types, including tied-arch, plate-girder, suspension, and truss and have often contacted the AIM program to validate the in-situ fatigue performance of a new design. The program has also been commonly contracted to evaluate the cause of observed cracking or estimate the remaining fatigue life of uncracked details. Load testing has also been successfully used to improve bridge rating analyses.
The AIM program, currently under the direction of ATLSS Director and Joseph T. Stuart Professor of Structural Engineering Richard Sause, continues to utilize its expertise to support the engineering needs of bridge and other infrastructure systems owners throughout the United States.
Expertise
The expertise of the AIM program encompasses:
Controlled load testing and structural evaluation
Remote sensing and long-term health monitoring
Fatigue and fracture analysis
Development of fatigue rehabilitation and retrofit concepts
Modeling, simulation, and prediction of behavior through finite element analysis
Data reduction, analysis, and interpretation
Dynamic testing (forced-vibration, ambient vibration monitoring)
Material testing and evaluation
Industrial Testing Program
The ATLSS industrial testing program assists industrial and engineering firms of all sizes with testing, research, and development of products and systems by offering technical capabilities that can yield valuable data as well as technical assessments of existing structures. The program utilizes the unique engineering capabilities of both the ATLSS large-scale multi-directional experimental laboratory and the Fritz Engineering Laboratory and the extensive experience of its leadership and support staff to technically address the project at hand.
Facilities
ATLSS Large Scale Multi-directional Experimental Laboratory
The ATLSS Large Scale Multi-directional Experimental Laboratory was dedicated in 1989 as part of the ATLSS National Engineering Research Center established by the National Science Foundation. The primary features of the laboratory are the 102 x 40 foot strong floor and fixed concrete reaction walls, up to 50 feet in height, which encircle three corners of the floor. Multi-directional loads and motions are applied by computer controlled hydraulic actuators to scaled or full size test structures comprised of any material. The laboratory boasts a wide range of instrumentation and data acquisition technologies, in addition to faculty and full-time staff that are available to assist in the execution of a project. A wide range of tests with static, pseudo-dynamic, dynamic, fatigue, impact, and seismic loading can be performed. In 2004, the capabilities of the industrial testing program were enhanced with the addition of the Network for Earthquake Engineering Simulation (NEES) Real-Time Multi-Directional (RTMD) equipment site, which allows for multi-directional real-time seismic testing in combination with real-time analytical simulations, to investigate the seismic behaviour of small and large scale structural components, structural sub assemblages, and systems.
Fritz Engineering Laboratory
The Fritz Engineering Laboratory has been at the forefront of civil engineering research at Lehigh University since 1909. The laboratory currently features universal testing machines with up to 5,000,000 pound capacities, a dynamic test bed with static and fatigue testing capabilities, and a wide range of test instrumentation and data acquisition capabilities. The laboratory also boasts dedicated faculty and full-time research and laboratory technical staff which are experienced in the development and execution of calibrations, standardized tests, customized tests, and applied research.
Resources
The AIM program owns a fully equipped field testing vehicle, a Dodge Sprinter S3500 cargo van with high roof and extended wheelbase, which provides extreme mobility and flexibility to respond to project demands upon short notice. This vehicle is equipped with a mobile office and stores a cache of tools, instrumentation, and other supplies regularly required for field monitoring projects.
The data acquisition and instrumentation capabilities include:
Rugged high-speed multi-channel digital data acquisition systems equipped with advanced signal processing capabilities
Rainflow cycle counting for fatigue evaluations
Wireless remote sensing
Remote data collection
Wide array of high fidelity sensors capable of measuring load, strain, displacement, acceleration, rotation, temperature, wind speed and direction
Digital video cameras with remote pan, zoom and tilt operations; a 4 channel digital video recorder (DVR) can be configured for continuous video monitoring.
Materials Testing Program
The ATLSS Engineering Research Center operates a Materials Testing Program, which draws on the resources available in the Center’s Mechanical Testing Laboratory, Metallography and Mircroscopy Laboratories, and Robert E. Stout Welding and Heat Treating Laboratory. Included in these capabilities are 60,000 and 600,000 pound universal testing machines and a Charpy V-Notch fracture toughness testing machine for conducting standard mechanical property tests of metallic, cemenitious, and composite construction materials. Additionally, metallographic sample and material characterization capabilities are available, including hardness and microhardness, light optical microscopy, and scanning electron microscopy. A materials engineer is dedicated to support the program’s technical projects.
Real-Time Multi-Directional Equipment Site
As part of the George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES) Program, Lehigh University has established the Real-Time Multi-Directional (RTMD) earthquake simulation facility at the ATLSS Engineering Research Center. The RTMD earthquake simulation facility is a next-generation earthquake research facility for seismic performance evaluation of large-scale structural systems. This facility has advanced experimental and analytical simulation capabilities to test and validate complex and comprehensive analytical and computer numerical models, leading to advances in earthquake engineering and experimental methods.
The facility features a multi-directional reaction wall, five dynamic actuators, advanced instrumentation, and a tele-participation system consisting of real-time streaming data and video. Hydraulic power for the servo-actuator system is supplied by a system consisting of five pumps and three banks of accumulators that enables strong ground motion effects to be sustained in real-time for up to 30 seconds. Real-time multi-directional seismic testing of large-scale structural components and systems at the RTMD earthquake simulation facility can be performed using either the effective force method, pseudo-dynamic testing method, or the pseudo-dynamic hybrid testing method. Distributed hybrid pseudo-dynamic testing can also be performed using the RTMD facility in conjunction with other laboratory sites.
Lehigh University
Notice: Please contact international@erc-assoc.org if you represent this Research Institution and have identified any required additions or modifications to the above information.