Publications
Transactions of the 26th International Conference on Structural Mechanics in Reactor Technology. Berlin/Potsdam, Germany. July 10-15, 2022.
This paper presents the framework for a performance-based seismic assessment of coupled soil-structure-fluid systems via integrated 3D finite element (FE) analysis. The proposed strain-based performance approach reduces the conservatism and uncertainty associated with the stress-based approaches while better aligning with the performance requirement of the structure to maintain its functionality. By optimizing the modeling approach […]
Transactions of the 26th International Conference on Structural Mechanics in Reactor Technology. Berlin/Potsdam, Germany. July 10-15, 2022.
The standard assumption of modelling the vertical component by vertically propagating P waves underestimates the spatial variability of the vertical ground motion over the dimension of the foundation of large structures, which can lead to very large vertical floor spectra at high frequencies. Modelling the vertical ground motion as inclined P-SV waves and including stochastic […]
Transactions of the 26th International Conference on Structural Mechanics in Reactor Technology. Berlin/Potsdam, Germany. July 10-15, 2022.
Introduction Currently, spent nuclear fuel (SNF) is stored in onsite independent spent fuel storage installations (ISFSIs), which are dry storage facilities, at 55 nuclear power plant sites. Because the SNF will be stored at ISFSIs for an extended period of time, there is growing concern with regards to the behavior of the SNF within these […]
Transactions of the 26th International Conference on Structural Mechanics in Reactor Technology. Berlin/Potsdam, Germany. July 10-15, 2022.
Steel-plate composite (SC) structures consist of infilled concrete between steel faceplates with shear ties connecting the front and back faceplates. Shear ties can be made of bars, rebars, plates, or steel shapes. Currently, there is a tendency in the nuclear industry towards utilizing plate shear ties since they provide better handling performance of the skeletal […]
Transactions of the 26th International Conference on Structural Mechanics in Reactor Technology. Berlin/Potsdam, Germany. July 10-15, 2022.
Seismic analysis, including the consideration of soil-structure interaction (SSI), is an important and required step in the design and licensing of nuclear power plant structures, systems, and components (SSCs) that are important to safety. Historically, the SSI analysis of nuclear structures has been performed using equivalent linear methods. However, there has been considerable industry exploration […]
SuperPile 2021 - Deep Foundations Institute
The Synchronous Condenser Unit 3 (SC3), in charge of adjusting the electric power between the hydroelectric generating facility and the transmission grid, experienced undesirable vibration levels during its initial stages of operation. The source of the high vibration levels is attributed to the resonant dynamic interaction between the condenser, its foundation, and the supporting soil […]
DOE/NRC Natural Phenomena Hazards Meeting, Rockville, Maryland, October 23-24, 2018
This presentation summarizes the methodology and results from a recent seismic evaluation of a safety-class fire water storage tank. Tanks such as this are common at both DOE and NRC regulated nuclear facilities and their safety function following earthquake is relied upon for various design scenarios. The evaluation was initiated out of a concern for […]
3rd International Conference on Performance-based Design in Earthquake Geotechnical Engineering (PBD-III)
Seattle Public Utilities (SPU) has four large, buried concrete reservoirs constructed between 2006 and 2013 and ranging in size from 5MG to 64MG (20 to 240 million litres). These reservoirs are essential for maintaining post-seismic event fire suppression and domestic water supplies for the City of Seattle, Washington. Three of the reservoirs are roughly square, […]
14th International LS-DYNA Users Conference 2016
Arbitrary Lagrangian – Eulerian (ALE) methodology has been used in Fluid – Structure Interaction (FSI) analyses with LS-DYNA® for a variety of problems. Validation of ALE solutions by comparison with experimental data provides assurance that the solutions represent the physical world. A water tank under horizontal harmonic excitation tested by O. M. Faltinsen and O. F. Rognebakke [1] […]
Western Bridge Engineer's Seminar 2015
This study pertains to the numerical and experimental studies of an unprecedented multi-movement rail joint designed for the Homer M. Hadley Memorial Bridge located in Seattle, Washington. The bridge carries the westbound and reversible lanes of Interstate 90 across Lake Washington and is the widest and fifth-longest floating bridge in the world. As a part […]
California States Lands Commission (CSLC)
Pursuant to Government Code 4526, The California States Lands Commission (CSLC) announced [1] its need for Engineering Consultants to perform a number of structural analyses with ADINA finite element program [2]. SC Solutions was selected to conduct this project for CSLC. As a part of this project, SC Solutions examined the MOTEMS [3] requirements applied to several typical pile-supported […]
DOE/NRC Natural Phenomena Hazards (NPH) Meeting at the U.S. Nuclear Regulatory Commission Headquarters in Rockville, MD in October of 2022.
Because spent nuclear fuel (SNF) will be stored at interim spent fuel storage facility installations (ISFSI) for an extended period of time, there is an unreviewed condition related to the behavior of the SNF within these dry storage systems during earthquakes. Thus, Sandia National Laboratory is leading a shake table test program to better quantify […]
Structure Magazine, April 2022
Undercut anchors are an ideal post-installed anchor category as their load transfer mechanism is bearing, similar to that of headed studs cast into concrete. Their mechanical interlock prevents the anchor from pulling out and results in high load capacities and small displacements. They can be designed such that with sufficient embedment depth and other design […]
Pacific Earthquake Engineering Research Center (PEER) Researcher's Workshop, May 17, 2021
The US Department of Energy’s Spent Fuel and Waste Science and Technology (SFWST) program is investigating the mechanical loading of spent nuclear fuel (SNF) to close knowledge gaps and inform the range of relevant loads for mechanical testing of irradiated SNF. The SFWST program has performed full scale dynamic testing of multimodal transportation and cask […]
Transactions of the 25th International Conference on Structural Mechanics in Reactor Technology. Charlotte, NC. Aug. 4-9, 2019.
The effects of foundation embedment on the seismic response of structures have long been recognized in the analysis and design of nuclear power plant (NPP) structures. Some design standards allow simple methods to address the embedment effects. However, these methods are only suitable to consider the effects of soil embedment on uniformly embedded structures. There […]
Transactions of the 25th International Conference on Structural Mechanics in Reactor Technology. Charlotte, NC. Aug. 4-9, 2019.
Inclusion of incoherency effects in soil-structure interaction (SSI) analysis provides a more realistic determination of earthquake induced building structural responses than those obtained considering coherent ground motion. Separately, industry demand for high-fidelity, comprehensive coupled structural models that often directly include structure-soil-structure interaction (SSSI) effects continues to increase. Combining incoherency and SSSI effects has raised questions […]
Transactions of the 25th International Conference on Structural Mechanics in Reactor Technology. Charlotte, NC. Aug. 4-9, 2019.
In this study, the seismic impact between two adjacent structures with different lateral stiffness is investigated through a computational model. The method used for the impact analysis in this study is based on the Hertz contact law combined with a non-linear damper activated during the impact to allow consideration of energy dissipation during the impact […]
Transactions of the 25th International Conference on Structural Mechanics in Reactor Technology. Charlotte, NC. Aug. 4-9, 2019.
The seismic SSSI effects in the nuclear island buildings for a representative plant are considered. The nuclear island consists of four buildings. The seismic SSSI effects on the lightest and smallest building (building of interest) are analyzed with two different approaches (ASCE 4-16, 2017). First, a model that includes all four buildings (explicit SSSI model) […]
Transactions of the 25th International Conference on Structural Mechanics in Reactor Technology. Charlotte, NC. Aug. 4-9, 2019.
In the nuclear power industry large pile groups are used world-wide at soil sites with soft and weak near-surface soil layers as foundations for both safety and non-safety related structures. Entire nuclear power plant (NPP) facilities are founded on piles in areas of low to moderate seismicity, as for example in Belgium (Doel 3), Brazil […]
Transactions of the 25th International Conference on Structural Mechanics in Reactor Technology. Charlotte, NC. Aug. 4-9, 2019.
This paper introduces a new alternative for soil-pile-structure interaction analysis, based on established soil-pile interaction theory, which accommodates a wide range of foundation conditions. A description of the theoretical formulation and its implementation into the prevalent SASSI software framework via SC-SASSI (SC Solutions, 2018) is provided in this paper, including examples and usage recommendations. A […]
Transactions of the 25th International Conference on Structural Mechanics in Reactor Technology. Charlotte, NC. Aug. 4-9, 2019.
The benefits of seismically isolating nuclear power plant buildings, in terms of reducing seismic risk, are well established but the possible impacts on overnight capital cost are unknown. Projects funded by EPRI and ARPA-E are now underway to characterize possible reductions in overnight capital cost of new build plants, with a focus on the financial […]
Transactions of the 25th International Conference on Structural Mechanics in Reactor Technology. Charlotte, NC. Aug. 4-9, 2019.
This paper proposes enhancements to the equivalent linear approach of simulating the site soil response for the seismic soil-structure interaction analysis of structures in a nuclear power plant to better represent the physical behavior of soil. The equivalent linear site response approach in frequency domain is the state of practice which is widely used to […]
DOE/NRC Natural Phenomena Hazards Meeting, Rockville, Maryland, October 23-24, 2018
A key step in the formulation and solution of the soil-structure interaction (SSI) problem is the calculation of the displacements of the soil without the presence of a structure, also known as free-field displacements. The free-field displacements are used as basis for the formulation of the compliance matrix or soil flexibility matrix. A new approach […]
DOE/NRC Natural Phenomena Hazards Meeting, Rockville, Maryland, October 23-24, 2018
Review of existing literature on the topic of building pounding suggests that impact can not only result in potential structural damage, but can also result in large high frequency accelerations, that could cause malfunction of equipment installed within the buildings. The magnitude of impact effects caused by pounding is case-specific, and reliable methods to approximate impact effects are limited, […]
TINCE 2018 - Technological Innovations in Nuclear Civil Engineering, Paris, France, August 29-31, 2018
A comparative seismic soil-structure-interaction (SSI) study was performed for the reactor building of a nuclear power plant in Switzerland in order to gain insights into the relative significance of nonlinear response effects which may be triggered during beyond-design-basis seismic events. The case study reactor building is founded on 20m of gravel underlain by bedrock and with an embedment depth […]
Structures Congress 2018, Fort Worth, Texas, April 19-21, 2018
An offshore Gravity Based Structure (GBS) and the underlying seabed soil layers were analyzed to evaluate the seismic retrofit strategy to extend the platform’s useful life and increase its production capacity. The GBS is a steel structure consisting of a box shape caisson substructure and a Box Girder Deck (BGD) which supports the topsides. The BGD and topsides […]
2018 International Congress on Advances in Nuclear Power Plants, Charlotte, NC, April 8, 2018
Recent studies have demonstrated that the capital cost of new nuclear is not dominated by the Nuclear Steam Supply System (NSSS) and balance-of-plant (BOP) technologies, but rather by the indirect costs, i.e. how the plants are built (including labor costs), engineering costs (including licensing) and owner’s costs (especially interest during construction). Therefore, cross-cutting technologies that […]
Transactions of the 24th International Conference on Structural Mechanics in Reactor Technology. Busan, South Korea. Aug. 20-25, 2017.
For decades, the System for Analysis of Soil Structure Interaction (SASSI) program and its derivatives has been an accepted and favoured analysis tool for treatment of seismic soil-structure interaction (SSI) effects on nuclear facilities. With continued advances in the fields of structural and geotechnical engineering, and increasing detail and refinement of analysis models, SASSI has […]
Transactions of the 24th International Conference on Structural Mechanics in Reactor Technology. Busan, South Korea. Aug. 20-25, 2017.
The nuclear industry has been a pioneer in recognizing the importance of Soil-Structure Interaction (SSI) and its effects on the dynamic response of structures and components during an earthquake. Equivalent linear analysis in frequency domain (ELFD) is the current state of practice for performing seismic SSI analysis of nuclear facilities. While the ELFD method produces […]
Transactions of the 24th International Conference on Structural Mechanics in Reactor Technology. Busan, South Korea. Aug. 20-25, 2017.
Base isolation will substantially reduce horizontal seismic demands in structures, systems and components (SSCs) in nuclear facilities, thus providing opportunities to increase seismic safety and reduce construction cost. Although past studies have characterized the benefits of seismic isolation in terms of increased safety, the possible reductions in construction cost have not been quantified. The over excavation, additional reinforced concrete […]
ACSE Innovation Contest
The hallmark of an advanced economy is the extent, condition, and efficiency of its public and private infrastructure. The advent of Blockchain technology gives society the capability to represent value stored in infrastructure with an electronic token validated by engineers. The implications are staggering. Markets would elevate the engineering profession to the status of financial […]
3rd International Conference on Performance-based Design in Earthquake Geotechnical Engineering (PBD-III)
Underground structures are an integral part of civil infrastructure and play an ever-increasing role in a rapidly urbanizing world. Underground structures have generally performed better than aboveground structures during earthquakes when transient motions are considered. Nevertheless, underground structures are vulnerable to ground failure such as fault displacement, liquefaction and slope instability. This paper reviews past performance of […]
Soil Dynamics and Earthquake Engineering, Volume 92, January 2017, Pages 551-560
In practice it is common to estimate site effects using a single proxy, or single variable such as 30 m shear wave velocity (Vₛ₃₀) or site period. Many studies have investigated merits of proposed proxies with contradicting recommendations. Yet, most studies indicate the single proxy approach is less than ideal, resulting in large uncertainty. To provide a better […]
DOE Natural Phenomena Hazards (NPH) Workshop 2016
The equivalent linear approach in frequency domain (ELFD) is the current state of practice for performing seismic soil-structure interaction (SSI) analysis of nuclear facilities. Although the ELFD method would produce reliable results for small to medium intensity ground motions, its application to analyze structures under large seismic events is debatable. The latter is due to the […]
DOE Natural Phenomena Hazards (NPH) Workshop 2016
As a partial response to post-Fukushima Near-Term Task Force (NTTF) Recommendation 2.1 from the Nuclear Regulatory Commission (NRC), several operating nuclear power plants commissioned seismic probabilistic risk assessment (SPRA) studies to evaluate the impact of modern seismic hazard estimates on seismic safety. The current study focuses on the structural response analysis performed for various structures […]
Engineering Mechanics Institute Conference 2016
The seismic Soil-Structure Interaction (SSI) analysis of nuclear facilities is usually performed in frequency domain where the response of the soil-structure system’s components is modeled as linear. The linear response assumption may be appropriate for small- to medium-intensity seismic events; however, the Seismic Probabilistic Risk Assessment (SPRA) of nuclear facilities requires the study of the […]
ASCE Geotechnical and Structural Engineering Congress 2016
The safety related structures in nuclear power plants often need to be designed to withstand the effects of tornado generated missile impacts. The heaviest missile to consider is often an automobile which is a soft missile due to its large deformations during the impact. Due to the large mass of this missile, it often has the highest kinetic […]
Mexican Association of Civil Engineers, Mexico City, 2015
Attending an invitation from the Mexican Society of Geotechnical Engineering (SMIG), the Mexican Society of Structural Engineering (SMIE) and the Mexican Society for Earthquake Engineering (SMIS), Julio Garcia of SC Solutions presented a lecture on the topic: Seismic Analysis of Nuclear Power Plants. The event was held on December 3, 2015 at the Mexican Association of Civil Engineers, […]
California Strong Motion Instrumentation Program SMIP 2015
A new procedure for rapid post-earthquake safety evaluation of bridges is being developed, using existing strong motion records, PGA data immediately available following an earthquake, and fragility databases, to assist responsible parties in making timely, informed decisions regarding post-earthquake bridge closures. The New Carquinez Bridge was selected to demonstrate the procedure. This paper provides a […]
Western Bridge Engineer's Seminar 2015
Over two hundred million trips are taken daily across structurally deficient bridges in the nation’s 102 largest metropolitan regions, per 2013 ASCE Report Card for America’s Infrastructure. The average age of the nation’s 607,380 bridges is currently 42 years. The nation has an entire generation of bridges, constructed in the 1950s and 1960s, that need […]
Engineering Mechanics Institute Conference 2015
Fluid-Structure Interaction (FSI) may contribute significantly to the structural demands on fluid storage structures during the seismic events because of sloshing and impulsive wall pressure. A variety of simplified approaches are used in engineering practice to quantify the FSI effects via either closed-form solutions or the use of discrete analogs to represent the fluid domain. […]
Engineering Mechanics Institute 2014
A series of nonlinear seismic time history analyses was conducted in LS-DYNA to evaluate the seismic performance of buried reinforced concrete fluid storage structures. This study is aimed at presenting a sophisticated modeling procedure in time domain for soil-structure (SSI) and fluid-structure (FSI) interactions with limited focus on FSI. The current state-of-practice for modeling SSI […]
Tenth U.S. National Conference on Earthquake Engineering 2014
Code-based procedures rely on a simplified sub-structure approach for analyzing soil structure interaction (SSI) effects. This simplified approach separates the site response analysis (SRA) from the SSI problem. Such separation prohibits a holistic view of the entire soil-structure system under seismic loading. Specifically, perspective is lost on the concurrent period migration of the structure and […]
33rd International Conference on Ocean, Offshore and Arctic Engineering Proc. ASME. 45431; Volume 4B: Structures, Safety and Reliability, V04BT02A054. June 08, 2014 OMAE2014-24652
Continuous structural integrity monitoring (SIM) can be a valuable complementary tool to the current practice of periodic inspections in detecting damage in jacket platforms. This paper demonstrates the technical feasibility of adopting the recent advances in onshore SIM technology for offshore jacket platforms. Both the analysis method and hardware technology are investigated. To demonstrate the […]
Proc. SPIE Vol. 9063, 906312 (9 March 2014) Nondestructive Characterization for Composite Materials, Aerospace Engineering, Civil Infrastructure, and Homeland Security 2014 • © 2014 SPIE; doi: 10.1117/12.2044539
This study investigated a number of different damage detection algorithms for structural health monitoring of a typical suspension bridge. The Alfred Zampa Memorial Bridge, a part of the Interstate 80 in California, was selected for this study. The focus was to implement and validate simple damage detection algorithms for structural health monitoring of complex bridges. […]
Proc. SPIE 9063, Nondestructive Characterization for Composite Materials, Aerospace Engineering, Civil Infrastructure, and Homeland Security 2014, 906311 (9 March 2014) • © 2014 SPI; doi: 10.1117/12.2044617
This study introduces an efficient procedure to estimate the structural response of a suspension bridge in real time based on a limited set of measured data. Unlike conventional techniques, the proposed procedure does not employ mode shapes and frequencies. In this study, the proposed technique is used to estimate the response of a suspension bridge […]
Concrete International, The magazine of the American Concrete Institute -- an international technical society
This peer-reviewed article presents an investigation conducted to determine the behavior of bridge column reinforcing bar cages subjected to lateral loads. Two full-scale cages were tested until failure to determine the response to lateral displacement and identify progressive collapse sequences. Using the results from the experimental study, nonlinear static and dynamic finite element analyses were […]
Western Bridge Engineer's Seminar 2013
The SR520 North West Approach replacement project will consist of 40 spans of isolated, elevated roadway. The design includes approximately 100 triple friction pendulum isolator bearings atop columns supporting the superstructure. A detailed ADINA model was generated, which used a nonlinear user-derived element for the isolation bearings, coupled in the two principal horizontal directions. During […]
Seventh National Seismic Conference on Bridge and Highways (7NSC), Bridge Resilience for earthquake and other natural hazards, Oakland, May 20-22, 2013.
Three important challenges in the finite element modeling and seismic analysis of a suspension bridge are addressed in this paper. Firstly, since suspension bridges are highly nonlinear geometrically, the construction sequence should be simulated to accurately characterize the initial stresses in the structural components. For this purpose, an automated procedure that iteratively corrects the geometry […]
Seventh National Seismic Conference on Bridge and Highways (7NSC), Bridge Resilience for earthquake and other natural hazards, Oakland, May 20-22, 2013.
A Finite Element (FE) model which can precisely predict the actual dynamic responses of a bridge is necessary for accurate condition assessment and health monitoring purposes. However, most of the bridge FE models initially developed for design purposes may not be able to accurately simulate the current response of the bridges due to various reasons. […]
Journal of Geotechnical and Geoenvironmental Engineering, Volume 140, Issue 3 (March 2014) 10.1061/(ASCE)GT.1943-5606.0000957, 04013022
The results of three full-scale lateral load tests of cast-in-drilled-hole RC piles are evaluated to provide insights into the soil-pile interaction behavior as represented by p-y curves (p 5 soil reaction/length; y 5 lateral pile deflection) spanning from elastic conditions to mobilization of the soil capacity. The test sequence enables evaluation of the diameter effects on the […]
ASCE, 2013 Structures Congress, Pittsburg, Pennsylvania, May 2-4, 2013.
This study pertains to the vehicle–bridge interaction analysis of Homer M. Hadley Memorial Bridge located in Seattle, Washington. The bridge carries the westbound and reversible lanes of Interstate 90 across Lake Washington and is the widest and fifth-longest floating bridge in the world. Based on the proposed plan to design and construct a light rail […]
Structure and Infrastructure Engineering: Maintenance, Management, Life-Cycle Design and Performance, DOI:10.1080/15732479.2012.757793
This article presents the implementation of a calibration procedure for a finite element (FE) model of a state highway bridge using sensory data measured on the bridge. The objective is to modify the high-fidelity FE model of the bridge so that its dynamic behaviour matches, as closely as possible, that of the bridge under analysis. […]
IMAC-XXXI-Society for Experimental mechanics (SEM): Conference & Exposition on Structural Dynamics, Engineering Nonlinearities in Structural Dynamics, Garden Grove, California, February 11-14, 2013.
The addition of Light Rail Trains (LRT) to the Homer M. Hadley Memorial Bridge, the widest floating bridge in the world located in Seattle, Washington, is currently in its design process. The design team has concluded that a transition Track Bridge (TB) is necessary to accommodate large movements induced by the floating bridge in relation […]
Proc. SPIE 8347, Nondestructive Characterization for Composite Materials, Aerospace Engineering, Civil Infrastructure, and Homeland Security 2012, 834727 (April 26, 2012); doi:10.1117/12.916163
A Finite Element (FE) model which can precisely predict the actual dynamic responses of a bridge is necessary for accurate condition assessment and health monitoring purposes. However, most of the bridge FE models initially developed for design purposes may not be able to accurately simulate the current response of the bridges due to various reasons. […]
2011 American Control Conference, San Francisco, CA, USA, June 29 - July 01, 2011, pp. 3116 -3121, 2011.
G. W. van der Linden, A. Emami-Naeini, R .L. Kosut, H. Sedarat, and J. P. Lynch In this paper we focus on comparing three candidate approaches to the optimal placement of sensors for state estimation-based continuous health monitoring of structures. The first aims to minimize the static estimation error of the structure deflections, using the […]
Center for Civil Engineering Earthquake Research, Department of Civil Engineering/258, University of Nevada, Reno, NV 89557 November 2010
The lateral behavior and stability of bridge column rebar cages were investigated to reduce the potential of failure and collapse during construction. Rebar cages are temporary structures made of longitudinal and transverse reinforcing bars that are connected by tie wire connections. Recent collapses during construction exposed the vulnerabilities of these temporary structures to accidental loads […]
California Department of Transportation (Caltrans)
Caltrans’ Toll Bridge Seismic Retrofit Program involved performing vulnerability assessments and retrofit designs for the state-owned toll bridges. To determine bridge response and evaluate seismic performance, a finite element model of each toll bridge was created using the finite element program ADINA. Following recommendations of the Seismic Advisory Board the project main goals included the following: (a) update the […]
9th U.S. National & 10th Canadian Conference on Earthquake Engineering (9USN/10CCEE) Toronto, 2010
In the current state-of-practice of the performance-based design of structures, simplified procedures are often used to evaluate the deformation capacity of structural systems. One specific example is using the rotation limits for the deformation-controlled elements. This paper suggests the use of the strain limits, instead, and presents an efficient nonlinear analytical technique to compute the strain demand values for both […]
Nondestructive Characterization for Composite Materials, Aerospace Engineering, Civil Infrastructure, and Homeland Security 2010, Ed. Peter J. Shull, Aaron A. Diaz, H. Felix Wu, doi: 10.1117/12.847704, Proc. of SPIE Vol. 7649, San Diego, CA, USA, March 7-11, 2010.
In this paper we focus on the optimal placement of sensors for state estimation-based continuous health monitoring of structures using three approaches. The first aims to minimize the static estimation error of the structure deflections, using the linear stiffness matrix derived from a finite element model. The second approach aims to maximize the observability of […]
Nondestructive Characterization for Composite Materials, Aerospace Engineering, Civil Infrastructure, and Homeland Security 2010, Ed. Peter J. Shull, Aaron A. Diaz, H. Felix Wu, doi: 10.1117/12.848212, Proc. of SPIE Vol. 7649, San Diego, CA, USA, March 7-11, 2010.
Bridges are an important societal resource used to carry vehicular traffic within a transportation network. As such, the economic impact of the failure of a bridge is high; the recent failure of the I-35W Bridge in Minnesota (2007) serves as a poignant example. Structural health monitoring (SHM) systems can be adopted to detect and quantify […]
Reference: TUST1130, in: Tunnelling and Underground Space Technology incorporating Trenchless Technology Research. Online publication complete: 25-DEC-2008, DOI information: 10.1016/j.tust.2008.11.002
The seismic analysis of underground structures requires a careful consideration of the important effect of shear strains in the soil due to vertically propagating horizontal shear waves. These strains result in ovaling deformations of circular tunnels or racking deformations of rectangular tunnels. Closed-form solutions as well as numerical analyses are used to characterize this soil-structure […]
Sixth National Seismic Conference on Bridges and Highways: Seismic Technologies for Extreme Loads, 2008 Multidisciplinary Center for Earthquake Engineering Research State University of New York, 107 Red Jacket Quadrangle, P.O. Box 610025 Buffalo, NY 14261-0025 USA
The Auburn-Foresthill Bridge is a 2,428 ft steel suspension bridge that links the towns of Auburn and Foresthill, California and was built in1973. While it is ranked 3rd in the U.S., it is the tallest bridge in California. The bridge is located in the seismically active Foothills fault zone and is supported by two 403 ft tall unconfined […]
Transportation Research Board of the National Academies, 87th Annual Meeting, January 2008
Contact us at sc-structures@scsolutions.com for more information about this paper.
Rapid Excavation and Tunneling Conference Toronto, 2007
Precast concrete segmental lining systems have been gaining widespread use in seismically active areas and a single-pass version of such a system has been developed for use on the Silicon Valley Rapid Transit (SVRT) Project in San Jose, California. The response of tunnel linings to seismic shaking is often predicted using engineering judgment, elastic closed-form […]
You can read more about SC-Solutions’ work on the Cooper River Replacement bridge here. Contact us at sc-structures@scsolutions.com for more information about this specific paper, Seismic Design of the Cooper River Bridges Replacement Main Span Unit.
All large structures are vulnerable to earthquake damage. Local failures or total collapse of such structures represent not only immediate concern for loss of life and repair costs, but also major economic impacts due to loss of service. Engineers are asked to use advanced analytical procedures in order to assess the seismic vulnerability of existing structures, design with more […]
The Taiwan High Speed Railway is currently one of the world’s largest BOT infrastructure projects. Due for completion in 2003, the railway runs down the western side of Taiwan linking all the main centres of population. A major constraint on the design of the viaducts is the interaction between the track and the structure during […]
in Ports 2001: American’s Ports–Gateways to the Global Economy, 2004.
This paper presents the results of a detailed study of the batter pile-wharf deck connection at the Port of Oakland under their Wharf and Embankment Strengthening Program (WESP). It provides insight into the failure mechanisms of the designs studied and an evaluation of their reliability.
2nd UJNR (United States and Japan Cooperative Program in Natural Resources) Workshop on Soil-Structure Interaction, March 6 to 8, 2001, Tsukuba, Japan
The purpose of this paper is to present the Soil-Tunnel-Structure Interaction analysis performed for the “innovative” seismic retrofit of the Posey and Webster Street Tunnels located in the San Francisco Bay area. The tunnels are situated between two major faults, the Hayward Fault and the San Andreas Fault (Figure 1). Due to its close proximity […]
Ports '01: America's Ports: Gateway to the Global Economy: pp. 1-10
This paper presents results of a study conducted during the Seismic Risk Evaluation Phase of the Port of Oakland’s (California) Wharf and Embankment Strengthening Program (WESP). It estimates the response of existing piles with missing pile-driving records, to lateral load. The Pile Integrity Test (PIT) was used to determine pile tip elevations at the relevant […]
Report No. CCEER 00-8, Center for Civil Engineering Earthquake Research, Department of Civil Engineering, University of Nevada, Reno, November 2000
Computers and Structures, Volume 72 (1999), Pages 63-80 Pergamon Press
In this paper the results of SC Solutions’ performance-based evaluation of the as-built Unit 10 frame of the SR5 Lake Washington Ship Canal Bridge are presented. This unit is a three-span frame, located between bridge piers 24 and 27 on the north approach to the bridge and extends approximately 329 ft between expansion joints. A three dimensional […]
Structures for the Future - The Search for Quality IABSE Symposium, Rio de Janeiro, August 1999, Volume 83
Design criterion and methodologies have been developed and implemented that require bridges to be without significant damage following severe ground shaking. The design philosophy used to obtain these results is often referred to as “Performance Based Design.” These criteria differ from traditional codes in that they correlate levels of damage noted in laboratory testing and […]
Mid-America Highway Seismic Conference, March 1999, St. Louis, MS
The current AASHTO Specifications do not have adequate guidelines for seismic modeling and analysis of steel bridges. Bridge designers in seismic zones have always raised concerns about the adequacy of beam models in performing seismic analysis of steel bridges. This paper discusses the dynamic characteristics of five medium span steel bridges that were modeled using […]
13th ASCE Engineering Mechanics Division Conference held in Baltimore, June 13-16, 1999
In this paper the application of control theory to structural engineering has been presented from a structural engineering perspective. The objective of this paper is to summarize key steps that are required to design an active control system for a structure. Total acceleration feedback with H2/LQG controller is used in this paper. The structural control […]
Computers & Structures, Volume 72, Issues 1-3, 8 July 1999, Pages 233-251, Available online 24 May 1999, DOI information: 10.1016/S0045-7949(99)00008-5
As a part of the Posey and Webster Street Tubes seismic retrofit project, finite element analysis was used to study the soil–structure interaction behavior due to earthquake ground motions. This paper summarizes the nonlinear analysis activities for the Alameda Tubes. The overall objective of these studies was to estimate the responses of the as-built and […]
Seismic retrofit of steel bridges requires more advanced analysis techniques to determine capacities and predict inelastic performance parameters. Normal engineering analysis practice assumes linear-elastic behavior for structural members, which fails to reliably account for re-distribution of forces due to member non-linear behavior and dissipation of energy due to material yielding. The performance criteria for the 1958 Carquinez Strait […]
In Geotechnical Special Publication. (75 II ed., pp. 1380-1391)
Two immersed tube tunnels used for vehicular traffic in the seismically active San Francisco Bay Area were built over 30 years ago with little consideration to seismic effects. A seismic retrofit study was conducted to assess the vulnerability of the tubes to seismic shaking and to develop necessary retrofit schemes. Three-dimensional soil-structure interaction models of […]
Report No. UCB/CEE-Steel- 98/03, Department of Civil and Environmental Engineering, University of California, Berkeley, June 1998.
The purpose of this research was to provide the information required to finalize seismic retrofit design of the San Francisco-Oakland Bay Bridge. The emphasis was on conducting cyclic tests of half-scale specimens representing laced members and joints of the Bridge. The study indicated that the dominant failure mode of the members tested was local buckling […]
Computers & Structures, Volume 64, Issues 5–6, September 1997, Pages 1041-1052, Proceedings of the 11th ADINA Conference
This paper discusses the particular features and benefits of ADINA with respect to the requirements of advanced seismic analysis as applied to the Carquinez Strait Bridges in California. Major aspects of earthquake related analyses are discussed, i.e., static lateral push-over analysis, ground motion specification for dynamic analysis, and significant structural behavior phenomena associated with geometric […]
SC Solutions, Inc., 1451 Grant Road, Mountain View, CA 94040, U.S.A.
All large structures are vulnerable to earthquake damage. Local failures or total collapses of such structures represent not only immediate concern for loss of life and repair costs, but also major economic impacts due to loss of service. The 1989 Loma Prieta and 1994 Northridge earthquakes in California provided dramatic examples of the vulnerability of […]