Find session Abstracts, Speaker Bios and (in the near future) presentations below.
Some presentations will be available after the event, some may not be available for share.
Thursday, February 25, 2021
8:00 AM - 8:05 AM Introduction
8:05 AM - 8:50 AM Determining Structural Risk for NYC's Existing Buildings
Abstract: New York City’s 1.1M existing buildings house and provide work spaces to 8.3M people. In accordance with the laws and rules specified in our prior and current building codes, owners of these buildings shall maintain them safe. With the slow rate of decay of a building resulting from weathering and wear and tear, it is difficult to perceive the slow creep of a building, be it tall or small, from safe, to unsafe, to failure. Without targeted repairs and investment, inch by inch, in pieces or in whole, fail it will. Now add to this decay the rapid jump from unsafe to failure that occurs from poorly planned building alterations and negligent adjacent construction resulting in vacates, stop work orders, injuries and most unacceptable, fatalities.
Evaluating existing buildings for risk: Though ongoing extensive study of current and historic open data city records, past failures and more importantly, the substantial number of “near misses” (difficult to find and frequently overlooked), we have compiled, and look forward to sharing with our colleagues, our groupings of buildings classified by age, date of construction, architectural and structural characteristics, design manuals and, most importantly, their most commonly overlooked points of weakness and failure. We will explain how we have been able to determine likely points of failure in these groupings. So far and for the most part, our research informs us that clustering existing buildings by age, occupancy, structure and open data complaints (or lack thereof) is predictive. We have also been able to work out series of structural calculations that help map the highly stressed components of the buildings. Our presentation will deal with these macro issues as they relate to the outcome, a safe existing building.
Speaker: Tim Lynch PE, Chief Engineer of the Enforcement Bureau, City of New York’s Buildings Department
Tim Lynch is a New York State licensed Professional Engineer and certified Site Safety Manager with over 30 years of structural engineering design and construction experience. Mr. Lynch is the Chief Engineer for the Enforcement Bureau for the City of New York’s Buildings Department where he has served in a number of senior titles since 2005. Mr. Lynch’s duties are as follows:
•Code development focusing on the issues related to the structures and maintenance of our 1.1M existing buildings.
•Inter-agency communications and initiatives
8:50 AM - 9:35 AM Hudson Commons: Innovative Approaches to Vertical Expansion
Abstract: 441 9th Ave (AKA Hudson Commons) is a 700k SF renovation/addition situated on 34th street and 9th Ave in New York City by the Cove development group. KPF serves as the design and executive architect. The existing 8 story cast in place concrete building will be renovated and retrofitted with an additional 17 floors of steel on top of the existing building. A new cast in place concrete core is threaded through the existing structure from foundation through the new roof to provide lateral stability of the new larger building. The project is attempting LEED Platinum. This presentation will address the challenges and constraints of working within and in addition to an existing from demolition, to retrofitting to the new overbuild. Notable features of the project:
Speaker: Joseph Provenza PE, Senior Associate, WSPJoseph Provenza AIA PE LEED BD+C is an Associate with the WSP Building Structures team in New York, and leads the WSP Global Computational Design Group. Starting with WSP in NY in 2006, he has since held leadership roles in the Los Angeles, San Francisco and New Delhi Office before settled back into NY in 2014. Currently he is engaged with over three million square feet of high profile projects in various stages of design and construction including but not limited to Waterline Square, Hudson Commons and Newark Riverfront Square. Trained and licensed as both and Architect and Engineer, Joseph’s strongly multi-disciplinary background laid the groundwork for a pioneering role within the New York Building Structures practice with regards to office wide implementation of computational design tools in day to day practice.
9:35 AM - 10:20 AM Modifying Existing Old Buildings in NYC - Foundation Engineer's View
Abstract: More than 100 years ago, our firm’s founder stated that “Foundation engineering is an art in which there is no substitute for judgement based on wide experience.” This is still true for our profession but even more applicable when facing geotechnical challenges when working on existing old buildings in New York City.
When old buildings are modified or retrofitted, it is important to understand not only the subsurface conditions but also the existing foundation systems. Subsurface investigations have to be carefully planned considering the needs of the design. In New York City, it is essential to understand development history of the area. Many buildings might not be the first structures constructed at their sites and remnants of older buildings or other structures (e.g., waterfront structures) might still be present or incorporated into the current buildings. A review of historic references, maps and land books often provides the basis for understanding the building history.
For foundations engineers, it is very important to understand how buildings that need to modified or retrofitted, and their foundations were designed but also how they were constructed. Special attention has to be also paid to the potential impact of adjacent buildings and their construction, since some buildings share support (e.g., party walls) or provide support to each other. Engineering evaluations have to be supplemented by appropriate field explorations of existing foundations and, often, also foundations of adjacent buildings. Understanding of existing foundation systems often relies on experience with local construction and how it historically evolved based on previous projects. This understanding is essential in analyzing how foundations support structural loads above and how they will response to building modifications. Such analyses have to of course consider conditions of the foundations especially when they include materials, such as timber, that can deteriorate with time.
On projects involving existing buildings, foundation engineers are often asked to provide recommendations on reuse of existing foundations and recommendations for new foundations that might be required to replace or supplement the existing ones. A typical question is whether existing foundations can support new loads. The response can vary widely. For instance, if foundations are old timber mats bearing in fills over old river bottom deposits, any new loads exceeding loads that those foundations already experienced will cause significant settlement and potentially building damage. On the other hand, where a building is supported on foundations bearing on bedrock or stiff glacial deposits, increase in loads might not cause any issues to the building.
Recent projects throughout New York City will be used illustrate some of the geotechnical challenges discussed above. These will include historic buildings in South Street Seaport bearing on floating foundations, Tribeca buildings supported on old rubble walls and on timber piles, landmark Riverside Park townhouse with deep rock excavation in its cellar, Beekman building requiring grouting of foundation sands, old Wall Street tower with groundwater issues and few others.
Speaker: Jan Cermak, PE, Mueser Rutledge
Jan Cermak is a foundation engineer and Principal at Mueser Rutledge Consulting Engineers, with more than 23 years of experience with building construction in New York City. As Principal-In-Charge, he directs teams of geotechnical and foundation engineers in the firm working on various building, infrastructure, waterfront, and transportation projects. He has broad experience on complex geotechnical sites, and long history of developing innovative foundation and excavation support systems in urban environments. In addition to providing services for new construction in New York City, he has been involved in numerous projects where existing buildings have been renovated, modified or extended. This includes historic landmark buildings in excess of 200 years old to more recent buildings. Jan has expertise in a number of specialty areas, including design of ground improvement and earth retention systems, advanced numerical modelling, seismic design, and forensic engineering. He brings his expertise and full commitment to each project, small or large, which has earned him the trust of private developers, foundation contractors, and municipal clients.
10:20 AM - 10:25 AM Break
10:25 AM - 10:50 AM General Session
Check out our Platinum Sponsor's Presentation: Ashraf Habibullah, CEO of Computers & Structures, INC
10:50 AM - 11:35 AM Case Studies Comparing Past and Present
Abstract: When engineers work on new buildings, we use current analysis and design methods, which are close to (but not synonymous with) current codes. When we examine existing buildings, we have to look at them in the context of how they were analyzed and de signed or we will misunderstand them. To use a simple example, if we use ultimate strength analysis to review a 1940 reinforced-concrete beam designed using linear-elastic design, we will find it is much stronger in bending than its designers thought it was. If we use current code to establish the concrete shear capacity of that same beam, we will find that it is weaker than its designers thought it was. The beam has not become stronger in moment and weaker in shear over the years. Rather it is exactly as safe (or unsafe) as it always was, and our models of how it acts have changed.
To simplify a messy situation a bit, there is a statement at the beginning of the current NYC Building Code, “The legal occupancy of any structure lawfully in existence at the time of the adoption or a subsequent amendment of this code shall be permitted to continue without change, except” for those items specifically not grandfathered, such as sprinklering. Every building code has similar language grandfathering existing buildings. This clause, coupled with changes in each revision of the building code, means that the vast majority of buildings do not meet current code requirements for new buildings. But they do “meet code” because of this clause. In some cases, with the classic example being cast-iron columns, we are faced with an obsolete form of structure that was specifically abandoned because it was seen as unsafe, failing in an unpredictable and brittle manner. And there are methods of analyzing these columns that are far more re cent than their construction.
Note that obsolete forms of structure still present in buildings are not necessarily weaker than modern structure. A good example would be tile arch floors supported by steel beams. In the 1890s, it was demonstrated that the beams in such floors performed as if they were stronger and stiffer than they actually are. The nature of the floor arches – compressed against the beams by arching action, and strong in compression – allows them to act as a kind of composite flange. This is not a form of analysis we would use on new structure, but may be necessary to explain the performance of an existing floor.
In addition to current, past, and oddball forms of analysis, we have one last source of in formation: history. The load history of a building may be known or discoverable through research, the repair history may be known or discoverable on site, and the analysis history may be known or producible through reverse engineering. A house Old Structures has worked on in Manhattan provides an example of all of these factors.
Speaker: Don Friedman, PE, President Old Structures
Donald Friedman is president of Old Structures Engineering, PC, a structural engineering consulting firm for historic and old buildings, working for owners, preservation consultants, architects, contractors, and other engineers. A professional engineer with over 25 years experience in the investigation, analysis, and restoration of landmark buildings, Mr. Friedman holds a B.S. in Civil Engineering from Rensselaer Polytechnic Institute, an M.A. in Historical Studies from the New School for Social Research, and is a licensed engineer in New York, New Jersey, Pennsylvania, Connecticut, Vermont, Rhode Island, Massachusetts, and Virginia. He is certified in the practice of structural engineering by the Structural Engineering Certification Board, and is a Fellow of the Association for Preservation Technology and the American Society of Civil Engineers.
Mr. Friedman’s design experience includes the integration of modern construction into existing buildings with archaic and obsolete structural systems; repair and restoration of steel, masonry, iron, wood, and concrete structures; and the investigation of historic
buildings to determine structural type and condition. Representative projects include structural analysis of repair techniques at the 1846-1974 Fort Jefferson National Monument in the Gulf of Mexico; structural design of repairs to the crypts at the landmark New York Marble Cemetery; investigation and alteration feasibility study of Castle Clinton, the landmarked 1810 fort in New York; investigation of damage and repairs to Belvedere Castle in Central Park; façade analysis and design of new terra cotta sup ports for the 1906 Langham Apartments in New York; and frame analysis and alterations to the 1896 Gerken building in New York.
In addition to Mr. Friedman’s project work, he has taught engineering of historic buildings in the building conservation programs at the Rensselaer Polytechnic Institute, the University of Massachusetts at Amherst, and Columbia University; he has spoken at numerous conferences on such topics as the structural analysis of masonry facades, and
the failure of obsolete structural forms; he is the author of The Structure of Sky scrapers in America, 1871-1900, After 9-11: An Engineer’s Work at the World Trade Center, Historical Building Construction, and The Investigation of Buildings, and the co-author of Building the Empire State and The Design of Renovations. Refereed papers include “Methodology of Conservation Engineering,” “Cast-Iron Columns in Renovation Design,” “Hidden Intricacies: The Development of Modern Building Skeletons,” and “Ambiguity in Building Investigation.”
11:35 AM - 12:20 PM Shoring & Bracing of Existing Buildings
Abstract: Shoring and bracing are temporary means to maintain or enhance strength of buildings, whether existing or new construction. They may be employed as a temporary measure to enhance strength to support equipment, restore strength that has been lost or provide temporary support while modifying the load bearing system. Shoring and bracing material may be fabricated, job-built or assembled from reusable modular components. Design load considerations may come from code provisions, but they may also include project-specific conditions and contingencies for unknowns. Shoring and bracing are usually installed by skilled tradespeople who are familiar with the materials. Initial and periodic inspections may be carried out by tradespersons, but in some instances also by special inspectors or design professionals.
Design examples are provided for: (1) shoring to support equipment loads, (2) bracing for replacement of a masonry façade, (3) preservation of a façade while the building is demolished and (4) preserving a rowhouse after collapse of the attached building.
Speaker: Larry Shapiro, PE, HISA, Co-Principal of Howard I. Shapiro & Associates
Lawrence K. Shapiro, P.E. is the Co-Principal of Howard I. Shapiro & Associates and with over four decades of experience as a Professional Engineer, he has become a widely respected influence in the field of consulting and construction engineering design services in the New York City area and internationally.
Lawrence earned a Bachelor of Science in Civil Engineering at the University of Virginia in 1978 and has been a Licensed Professional Engineer since February 1983 in New York, Connecticut, Massachusetts, and New Jersey. He is a member of ASCE, ASME, NSPE, AWS, a Chairman of ASME B30.3, an ASME B30 Main Committee Delegate, a ASME P30 Member, as well as an ISO TC96 US Delegate. He has Co-Authored multiple editions of the book Cranes and Derricks, McGraw-Hill Publishing Co., with his father Howard I. Shapiro and brother and Co-Principal Jay P. Shapiro, as well as being the Co-Author of various articles in trade publications. He is especially proud to be a third generation professional engineer, and carrying on a tradition that continues to the next generation.
A video from our sponsor, CastConnex
Friday February 26, 2021
8:00 AM - 8:05 AM Introduction
8:05 AM - 8:50 AM A Resilience Approach to Building Retrofits
Abstract: Preserving historic structures is key to maintaining the fabric of New York City’s architecture; however, the increasing challenges of climate change threaten the viable future of these buildings. With climate change resulting in increasing heat and precipitation, coastal flooding and sea level rise, New York City’s historic buildings are experiencing increased vulnerability, damage and disruption. The goal of resilient building retrofits is not only to protect buildings from current climate hazards, but also to prepare for and adapt to future challenges while preserving the buildings’ character.
During this presentation, we will walk through our resilience approach for existing building retrofits. Beginning with the hazard analysis phase, we conduct a risk and resilience assessment that analyzes the climate-related shocks and stresses specific to the site over the building’s useful life, considering past events, current codes, standards, guidelines and hazard levels, along with future projections. The key climate-related shocks and stresses analyzed may include flooding, precipitation and heat, considering the effects of climate change. The vulnerability assessment phase then evaluates both site-specific and cascading impacts, such as power outages and disruption to transportation networks. While it is important to evaluate the structural integrity of the building, it is also critical to understand the architectural, MEP, and historic preservation aspects of the building when subjected to the aforementioned hazards, requiring interdisciplinary expertise and collaboration with other project team consultants.
These steps are key to assessing the expected performance of the existing building as-is, prior to any retrofits. The assessment may indicate a range of deficiencies, including building envelope vulnerabilities to hazards like flooding, damage to historic façade elements or MEP service equipment, inadequate structural capacity for future projected climate hazards, loss of municipal utilities, or business interruption and disruption of building activities during a hazardous event. Furthermore, the expected building serviceable life is dependent on the durability and serviceable life of individual building components and may decrease due to the identified deficiencies.
The expected performance may fall short of the desired building performance—often more so than the Owner and/or architect may anticipate—and a comprehensive analysis and understanding of this gap is key to evaluating the appropriate resilience measures for the building. Guided by site-specific vulnerability assessments, cost-effective resilience strategies may be identified which maximize opportunities for co-benefits and future climate adaptation and minimize recovery time to allow building function to resume as soon as possible after an event.
A comprehensive, site-specific climate risk assessment, including vulnerability analysis and evaluation of cost-effective resilience strategies, leads to the development of a comprehensive climate resilience strategy.
We will present case studies on the application of various aspects of our resilience approach across retrofits of buildings in New York City. We will discuss the implementation of flooding, heat, and precipitation-related resilience recommendations and provide an overview of the assessment process. Through this presentation, we will illustrate how—through a creative, interdisciplinary approach—we successfully navigate the stringent requirements and challenges inherent to existing building projects while maintaining a future-focused approach to enhance the overall long-term resilience of the building.Performance-Based Design (PBD) is a major shift from traditional structural design concepts and represents the future of earthquake engineering. These new procedures help assure that the design will reliably meet a desired level of performance during a given earthquake. The fundamental component of PBD is nonlinear dynamic analysis where an attempt is made to capture the real behavior of the structure by explicitly modeling and evaluating post-yield ductility and energy dissipation when subjected to actual earthquake ground motions. The goal is to achieve continued functionality after the earthquake and not just compliance to a design code that fundamentality aims only for life safety.
Speakers: Aditya Bhagath, PE, Associate, Thornton Tomasetti
Jennifer Mahan, Project Director, Thornton Tomasetti
Aditya Bhagath, P.E., is an associate at Thornton Tomasetti and has more than eight years of experience providing resilience and structural engineering consulting services on a wide variety of healthcare, retail, residential and commercial projects. His expertise includes multi-hazard climate risk and resilience assessments and adaption strategies and performance testing of installed food resilience measures. His project experience also involves structural investigations of existing buildings, including repairs and alterations to buildings, litigation support and forensic and emergency response for buildings and infrastructure damaged due to natural and man-made hazards.
Jennifer Mahan is a project director in Thornton Tomasetti’s Resilience team and brings more than five years of interdisciplinary structural engineering experience with a focus on resilient construction and housing design. She specializes in mitigative designs for a variety of natural disaster shocks and stresses, and in post-loss investigation and assessments, ranging from urban construction claims to hurricane response. Her responsibilities include the synthesis of scientific research, geospatial data, and post disaster crowd-sourced information, and the analysis of the latest design and building codes. Jennifer supports disaster response efforts and provides rapid engineering analysis and pre-event assessments for hurricane responses. She provides international risk and resilience assessments and uses her expertise to promote diverse and forward-thinking workplaces.
8:50 AM - 9:35 AM The Top 5 Myths of Masonry Restoration
Abstract: This seminar will look at various masonry building failure mechanisms and typical repair or retrofit solutions used, but are they the appropriate methods for long-term performance? Will the repair be worse than the original problem? We continue to see cracks in brickwork that has already been repaired. We see repointing mortar either falling out of the joint or causing the surrounding brick to spall. If we are more knowledgeable today than in the past, why are these problems still occurring? Various building intervention strategies and masonry restoration examples will be provided including repointing, lintel and flashing repair, and other common techniques. The top five misconceptions about restoration and retrofit of masonry will be highlighted. Finally, the use of trained craftworkers will be emphasized to avoid damaging historic masonry.
Speaker: Brian Trimble, PE, International Masonry Institute
Brian Trimble has over 30 years’ experience in the masonry industry, assisting design professionals in the design of masonry structures. He is a frequent lecturer to local, regional, and national construction industry groups. He has authored many articles and papers on various masonry subjects. Brian started his career with a brick manufacturer and worked at the Brick Industry Association for over 20 years serving in various positions. For the International Masonry Institute he coordinates activities in the Western PA and Western NY areas promoting masonry to a wide variety of audiences including owners, contractor, architects, engineers and craftworkers. Brian received his engineering education at Penn State University, where he received a Bachelor of Architectural Engineering Degree – Structural Design Option in 1986. He was granted his professional engineer’s license in the state of Virginia and is also registered in the state of Pennsylvania. Brian is actively involved in many organizations including the Construction Specifications Institute (CSI), American Society of Civil Engineers (ASCE), The Masonry Society (TMS), and the International Brick Collectors Association (IBCA). Brian is a Fellow of ASTM International.
9:35 AM - 10:20 AM Saving the Baby! Stories from Rescuing Structures from the Brink
Abstract: Old, vacant building structures can deteriorate to a point where they need extreme, careful attention just to maintain their stability. And sometimes, severe degradation of unused parts of occupied buildings has been allowed to occur without detection, so that emergency measures are necessary. This presentation is a sharing of the author's experiences in attempts to "save the baby" - older buildings - from the unchecked onslaught of weather and other sources of deterioration. Stories from over two dozen structurally challenged buildings are presented, grouped in the following categories:
We will also review the unique case of formerly interior masonry walls that have recently become exterior walls after the demolition or collapse of an adjacent building. This causes the wall to be subject to a different set of structural loading conditions. The wall is also newly exposed to the weather, as well as making the wall a part of the thermal building envelope. This may technically be beyond the purview of the structural engineer, but the combination of structural, thermal, and hygroscopic environmental changes need to be considered.
Finally, we’ll take a look at a few examples of poorly performed structural stabilization efforts that did not adequately address the need to ensure structural stabilization. The focus is on identifying patterns in the remediation work, in order to minimize the occurrence of similar situations in the future.
We’ll end with a short list of recommendations to keep in mind when dealing with structurally compromised or vulnerable buildings
Speaker: James D'Aloisio, PE, SECB, LEED AP, Principal at Klepper, Hahn & Hyatt
Jim is a principal with Klepper, Hahn & Hyatt, a structural engineering, landscape architecture, and building envelope services firm in East Syracuse, New York. An RPI graduate, he is a registered Professional Engineer in New York and Massachusetts, and has been certified by the Structural Engineering Certification Board (SECB) since its inception in 2007. He is a member and past president (1997-1998) of the American Society of Civil Engineers (ASCE) Syracuse Section, and a member of the American Institute of Steel Construction (AISC), the American Concrete Institute (ACI), the National Society of Professional Engineers (NSPE), and the Structural Engineers Association of New York State (SEAoNY). Mr. D’Aloisio is a member of ASCE/SEI’s Frost-Protected Shallow Foundations Committee, the Structural Condition Assessment of Existing Buildings Committee, and the Sustainability Committee, and is a member of Committee ACI 318-N. He is a trained infrared thermographer. Jim received the Order of the Engineer at Syracuse University in 1997. His 30-plus years’ experience as a consulting structural engineer has primarily involved the design of new building structures, additions, and modifications, and analyses, assessments, and investigations of structures and facades. Specialties include detailing to minimize structural thermal bridging, the use of alternative structural systems and design approaches that can reduce the CO2e emissions of structures and foundations. He has been involved in numerous special inspection projects, including developing statements of special inspections, performing inspections, and facilitating discrepancy resolutions. He has also performed over 150 structural forensic investigations, and he has presented over 300 times.
10:20 AM - 10:30 AM Break
10:30 AM - 11:00 AM Raffles and General Session
A video from out sponsor, Dewalt
Gold Sponsor Presentation - Jennifer Pazdon, PE Cast Connex
9/11 SE Memorial Committee - Jonathan Hernandez, PE
Check out this video from our sponsor, CTL Group
11:00 AM - 11:45 AM Capturing Structural Data in the Information Age: Past, Present, and Future
Abstract: Reality Capture (as we define it) embraces a collection of techniques through which we accumulate information about critical characteristics of an existing structural system: configuration, condition, and material properties. Ideally, these methods are non-destructive, minimally invasive, or remote. Physics is physics – sound, pressure waves, light, electromagnetic waves, materials, thermodynamics – but there has been evolution/revolution/innovation in computing power and algorithms, in sampling speeds, and in sensors and sources that are leading to changes in the way data is being collected, processed, and analyzed today. Wider adoption has led to competition amongst test equipment manufacturers, lower prices and innovation in product design and manufacturing, and development of new software. This in turn leads to technology fusion – using multiple technologies and techniques in combination to reduce probe size, pinpoint drill locations, and verify condition severity.
Digital photography is no longer just digital photography – with hyperpixellation, with photogrammetry, with digital twins, it is part of BIM and quantification and analysis. Ground penetrating radar (GPR) equipment has been evolving with multiple antennas and multiple frequencies now available in a single unit. Infrared and pulsed laser technologies, driven by autonomous vehicle development and augmented reality, will become part of the construction industry toolkit. This presentation will describe the state-of-the-art of Reality Capture – and give a glimpse into what is pending on the near horizon.
Speaker: Barry Drogin, Director of Non-Destructive Testing & Evaluation, SUPERSTRUCTURES
Barry Drogin is Director of Non-Destructive Testing and Evaluation at SUPERSTRUCTURES Engineers+Architects. A member of ACI Technical Committee 228, Mr. Drogin is well-known and respected throughout the metropolitan area for his broad knowledge, expertise, and practice. He administers SUPERSTRUCTURES’ NDT&E Quality Management System, trains their staff, evaluates and acquires new equipment and software, and is personally involved in performing field investigations and quality assurance testing for private clients as well as public agencies such as the School Construction Authority, DASNY, SUNY, CUNY, and the Port Authority of New York and New Jersey.
11:45 AM - 12:30 PM Good Neighbors: Protecting Existing Buildings and Infrastructure During Adjacent Construction
Abstract: Inherent in urban construction are challenges to protect and preserve existing buildings and infrastructure. Join us for an exploration of key concerns and opportunities to identify and manage risk when building in close proximity to neighbors.
Speakers: Michael J. Drerup, PE, Drerup Building Performance Engineering, PLLC
David E. Kosnik, PE, PhD, Senior Engineer, CTL Group
Michael J. Drerup has more than 20 years of structural engineering and building technology experience, with an emphasis on the performance, maintenance, repair, and retrofit of existing buildings and structures. He has planned and directed field and laboratory studies to evaluate the performance and durability of a variety of building systems, components, and materials, including structural systems, facades, and flooring. Mr. Drerup often works closely with specialists in other disciplines to assemble and manage teams tailored for larger and more complex assignments. He has also investigated numerous damage claims resulting from a variety of natural and man-made causes, including earthquakes, weather events, explosions, fire, impact, construction activities, and defective design or construction. Mr. Drerup has served as an expert witness in numerous cases, and has testified at deposition, trial, and mediation.
He has served on ASCE's Forensic Engineering Division for more than 15 years, including a term as Division Chair. During that time, he has led the development of continuing education seminars for engineers and architects, chaired ASCE's Fifth Congress on Forensic Engineering in Washington, DC, and served on the steering committees for several other conferences and symposia. Mr. Drerup has also represented ASCE internationally, including sponsored trips to forensic engineering conferences in India and Guatemala, and collaboration with the Institution of Forensic Engineers in the United Kingdom. He has served as a reviewer for ASCE's Journal of Performance of Constructed Facilities for more than 10 years, and was guest editor for a special topic issue on non-destructive evaluation of existing buildings and infrastructure. Mr. Drerup regularly publishes and presents on a range of topics including technical issues, professional practice, and architectural and engineering history.
Dr. David E. Kosnik draws from his dual background in civil and computer engineering to develop innovative performance monitoring and evaluation solutions for in-service infrastructure. His experience includes both long-term, continuous remote monitoring and short-term tests of occupied buildings, in-service bridges and structures, industrial facilities, movable structures, structures subject to ground vibration, and infrastructure vulnerable to hydraulic and geo-hazards. In addition, Dr. Kosnik is recognized internationally for his applications of acoustic emission technology to diagnose and evaluate structures and mechanical systems.
Dr. Kosnik’s monitoring strategies link measured quantities to specific limit states or performance metrics to support infrastructure management decisions, particularly those related to risk management, beyond-design-basis events, evaluation of retrofits and life extension efforts, characterization of damage progression, and early warning of possible disruption. In addition, he has developed software and methods to support aggregation and analysis of large, heterogeneous data sets (“big data”) for structural/mechanical performance monitoring, forensic engineering, and root cause analysis.
Prior to joining CTLGroup, Dr. Kosnik was a researcher at the Northwestern University Infrastructure Technology Institute, a multi-disciplinary center dedicated to research, education, and technology transfer to improve the nation’s transportation infrastructure.
Dr. Kosnik has authored a number of peer-reviewed journal articles and conference papers on structure monitoring, acoustic emission technology, and computing in civil engineering, and speaks at national and international technical symposia on a regular basis. He has taught units in structural investigation and monitoring in civil engineering courses and serves as a peer reviewer for academic journals, industry publications, and conferences.