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Tunnel and large cut-and-cover structure response to earthquakes is dominated by the surrounding ground, and, contrary to shallow-founded structures, does not depend on the inertial properties of the structures themselves. The focus of the underground design is on the free-field deformation of the ground and its interaction with the structure, i.e., a soil-structure interaction phenomenon. This paper summarizes the performance in recent past seismic events of deep, large underground structures, and then elaborates on their design approach: geotechnical, seismic criteria and structural factors. Analytical models are examined and conclusions drawn about their advantages and limitations. A general approach to the design of deep underground structures is illustrated through the on-going design of a particular project.

Widely varying material properties and joint configurations of the different pipe materials in common use have made it difficult to develop a coordinated thrust restraint design practice. This has resulted not only in significantly different guidance from AWWA design manuals for different pipe materials and agency requirements, but also widely varying design practices and company specific best practice approaches within the engineering community. Recognizing the need to develop consensus among practicing engineers as well as industry representatives and experts; in 2008, the members of the American Society of Civil Engineers (ASCE) Technical Committee on Pipeline Installation and Location formed a special task committee "Thrust Restraint Design of Buried Pipelines". The objectives of this task committee were: 1) To document current design practices of thrust restraint systems for various pipe materials; and compare current practices with theory. 2) To document the historical evolutions of the different design approaches, collect and compile field tests completed for different pipe materials. 3) To explore improvements to current practice, develop consensus, and propose recommendations for the development of a manual of practice. Since 2008, the task committee has prepared a white paper documenting the above objectives, held a workshop on thrust restraint design at the 2010 ASCE Pipelines Conference, and begun preparing a manual of practice (MOP) with the aim of improving and consolidating current practice into a more cohesive, if not universal approach. The task committee has also presented several papers at the last three ASCE Pipelines Conferences, documenting findings and progress. This paper briefly summarizes the progress by the committee since its inception in 2008, focusing on the progress made by the committee since the 2011 Pipelines Conference. It includes updates on the progress toward developing an analytical model for thrust restraint that is intended to form the backbone of the MOP. The analytical model will include factors that deal with: pipe-soil interaction including frictional and lateral resistance, pipe and joint flexibility, movement required to develop soil resistance and the limitations of joint materials, type and geometry on movement induced by thrust forces. Both thrust block and restrained joint methods are included. A simplified approach for common applications is also proposed.

This short paper presents revised information on the creep reduction factors used in the widely accepted method for geotextile mass per unit area design to prevent geomembrane puncture. The laboratory tests have been ongoing for 6-years and have not failed to date, leading to the tentative conclusion that published values of RF CR are quite conservative.

Bridge scour is a major cause of damage to bridge foundations and abutments. Approximately 17,000 scour-critical bridges exist in the United States. Scour-critical bridges are bridges with foundations that are unstable for calculated and/or observed scour conditions. This designation comes in part from the use of overconservative methods that predict excessive scour depths in erosion-resistant materials. Other available methods capable of overcoming this overconservatism are relatively uneconomical because they require site-specific erosion testing. This paper presents the assessment of two bridge case histories using the observation method for scour (OMS). OMS is a relatively new quantitative bridge-scour assessment method that accounts for time-dependent scour depth using field measurements. This method, which does not require site-specific erosion testing, was developed as a first-order assessment method for use in combination with routine bridge inspections. OMS uses charts that extrapolate or interpolate measured scour depths at the bridge to obtain the scour depth corresponding to a specified future flood event. The vulnerability of the bridge to scour depends on the comparison between the predicted and allowable (threshold) scour depths. The case histories presented in this paper consist of two Texas bridges, one designated as scour critical and the other as stable by the Texas Department of Transportation (TxDOT). Both stable and scour-critical bridges were selected to test OMS and also compare it with TxDOT's scour designation. These case histories serve to demonstrate the validity and applicability of OMS to full-scale bridges and to provide practitioners with two potentially useful real-life case histories that could serve as examples for engineering practice. A validation process was performed on the two case histories using historical scour measurements and flow data. The validation exercise showed that there was good agreement between predicted scour depths using OMS and field measurements. OMS was then applied as a bridge-scour assessment tool to both bridges using the 100-year flood as the future flood and the outcome of OMS compared with the original TxDOT designation. As a result of this, the originally scour-critical bridge was found to be stable according to OMS. The bridge originally designated as stable was also found to be stable according to OMS.

This paper describes wisdom of ancient engineering practice. The first wisdom is about a biology-based method for bridge-scour protection. A number of historical bridges across waterways in China served for more than 1000 years without significant structural damages. Protection provided by cultivated oysters is believed to be responsible for their excellent performance in scour protection. This offers a green approach to mitigate bridge scour. Another story is about natural hazard warning. A number of historical records indicated that major natural hazards are typically accompanied by abnormal behaviors of animals. The first successful prediction of earthquake occurrence is the Haining earthquake of China. The prediction and evacuation order was partially based on observed abnormal behaviors of animals. The paper also describes an innovative sticky-rick lime mortar used in ancient construction and bio-inspired sensors that potentially can improve existing understanding of bridge-scour mechanisms. In the authors' opinion, these historical heritages will continue to inspire emerging engineering practice.

Selected papers from Geo-Risk 2017, held in Denver, Colorado, June 4–7, 2017. Sponsored by the Geo-Institute of ASCE.This Geotechnical Special Publication contains 53 peer-reviewed papers on the us...

[EN] Although bridge fires pose a real threat, the topic is not covered in current design codes. This paper analyses information related to 154 cases of bridge fires, proposes classifying the damage levels suffered by a bridge during a fire, and establishes the main factors involved in bridge fire damage, which include: type of vehicle involved in the fire and its position, vertical clearance of the bridge, and the type of material composing the deck. The analysis shows that wooden bridges are the most vulnerable and that a tanker carrying gasoline under the bridge, or that is on the bridge and causes a serious spill under the bridge, is responsible for most of the fires that result in the collapse or demolition of the bridge., The research presented in this paper is sponsored by the Spanish Ministry of Education (Research Project BIA 2011-27104). The authors also thank Dr. J. Glassman for providing information for the present study and Dr. V. Yepes for his assistance. The authors are also grateful to D. Terrasa Diaz, J. Perez Armino, B. Black, and R. Campbell, who kindly gave permission to use the photos of Fig. 1.

[EN] One of the most critical stages for a structure s safety is its construction process, and this problem is even more acute in buildings with reinforced concrete structures. These structures are usually built by shoring successive floors, so that the most recently poured floor rests on the lower floors by means of shores. It is therefore vitally important to have calculation tools available to estimate the loads to which the shores and slabs will be subjected in each stage of construction. A number of calculation methods have been proposed to date, of which the one proposed by Grundy and Kabaila in 1963 is the best known and most frequently used. This paper analyzes the limitations of Grundy and Kabaila s method by means of a parametric study of finite-element method simulations that identified a large number of situations in which this method presented unsafe results in terms of the estimated loads on slabs. In many situations, therefore, applying this method could gravely affect a building s in-service behavior and durability. The paper s final objectives are to make the reader aware of the limitations of Grundy and Kabaila s method and the need to use the more refined methods that are now available to estimate the loads on shores and slabs in reinforced concrete buildings under construction, The authors would like to express their gratitude to the Spanish Ministry of Education, Culture and Sport for funding received under the FPU Program (FPU13/02466) and to the Generalitat Valenciana (GV/2015/063).

Airports, and in particular terminal buildings, present a real challenge for security and protective design engineers. The requirements for excellent accessibility, via road and rail connections, results in significant explosive threat vectors with few opportunities to provide adequate stand-off distances. Indeed, in terms of transportation infrastructure, airports present some of the most complex threat environments and present a real and credible target for malevolent attack, as has been proved by numerous case studies over the last few decades. When this complex threat environment is combined with architectural drivers to maintain accessible and open spaces to ease passenger flow and provide interesting and iconic structures, the headache for protective design engineers becomes more acute. This paper will present the state-of-the-art analysis methodologies and tools to design blast resistant airport structures and describe how their application can reduce human vulnerability, structural damage, and operational disruption. These tools include the employment of engineering-scale computational fluid dynamics (CFD) codes for the calculation of airblast loads, with the ability to model propagation through failing surfaces and complex external and internal geometries, including the potential effects of channeling. The paper will discuss the development of effective analysis tools to characterize contact and near-contact detonations against critical structural elements, as well as fast running models (FRMs) to facilitate analysis and protective design for these extremely challenging scenarios. Finally, a discussion of innovative design and retrofit options to increase the blast resistance of airport structures will be detailed, with a description of the testing programs used to validate these technologies.

This new PIANC reference will provide a set of recommendations to the global community involved in the initial design, analysis, or rehabilitation of marine oil and petroleum terminals. Potential users include owners/operators, port authorities, consulting engineers and others. It will also provide guidance for post-event inspection/rehabilitation and triggers for the re-assessment of an existing terminal. This paper is an update to one presented at Ports 2013 (Heffron et al. 2013) and provides a resolution of some key issues. This project has involved major oil companies, terminal operators, consultants and vendors and is scheduled to be published in 2016. This paper will focus on three major issues that have been resolved: 1. Design loads and applicable codes 2. Loads transferred to mooring dolphins from multiple quick release hooks 3. Geotechnical recommendations for each phase of the design For the design loads and codes, there are two primary options. The first is an American approach, involving the MOTEMS (2011), and conventional steel and concrete codes. And if the structures are steel tubular jacket type structures, API RP 2A would be applicable. The second approach is European, using the British Standards (BS 6349, 2016) and applicable Eurocodes. Other options presented include the English translation of Japanese standards, and references to the Spanish ROM and Russian codes. Each of these choices mandates specific loading combinations and design factors. The second issue involves the determination of the appropriate design load for the anchorage and design of mooring dolphins, with multiple quick release hooks. A simple equation has been agreed upon, based on the safe working load (SWL) of the hooks. This maximum calculated load is then compared to the maximum factored mooring load, and the larger of the two is used for the design of the dolphin. The third issue is what are the necessary geotechnical investigations and reports recommended for each phase of the design, from pre-FEED, FEED and final design. A table of recommended actions and studies is provided, and gives guidance to both the engineer and the client, to ensure that the resulting design in based on sound geotechnical tests and studies.

Shortly after completion of constructing Port Freeport’s new multi-purpose wharf, significant differential horizontal movement and vertical settlement of the wharf was detected. These movements far exceeded the anticipated displacements expected for this wharf. Placing it into service in its current condition and loading it with heavy cargo and equipment would have caused more damage and potential structural failure. To prevent further deterioration and to restore the wharf to its intended function, Port Freeport authorized repair work for its newly constructed wharf. This paper presents an overview of issues encountered during the wharf remediation work and their resolution, mostly employing simplified methods to efficiently tackle complex engineering and construction issues. It provides a better understanding and appreciation on how to effectively address field and design issues without compromising overall engineering design and schedule. This paper also emphasizes the importance of promptly recognizing problems as they arise and approaching them methodically.

The damage caused by Hurricane Katrina and the Tohoku tsunami caused local and federal agencies to consider more robust structures that provide improved protection to coastal communities from severe storm conditions. This paper addresses the design, permitting, and construction considerations of two coastal projects that include: a hurricane storm surge barrier and a tsunami resistant marina. A key portion for these projects required defining the environmental conditions, determining limiting characteristics, strengthening design elements, incorporating permit restrictions, and overcoming construction challenges. Working collaboratively with regulators and contractors, these coastal protection structures were constructed to provide improved protection for their respective waterfront communities. This paper discusses the damage from severe events, the design approach, the regulatory, and permitting restrictions, improve the recovery time for future storm or tsunami damage and lessons learned for future storm events.

This paper will discuss the empirical results of incorporating composite paving interlayers within pavement sections of streets located on Terminal Island at the Port of Los Angeles. Historically, this area is subject to extensive pavement distress caused by high volumes of terminal truck traffic. In an effort to minimize impacts to operating terminal traffic, the Port of Los Angeles developed the use of experimental pavement sections to reduce the construction time, traffic control set up, and cost of the street repair work while still maintaining the structural integrity of the roadway. The objective of the experimental pavement overlay projects was to provide an effective and sustainable alternative to traditional full-depth street reconstruction with the incorporation of geocomposite materials. The primary focus of this paper will be on a lightweight polypropylene paving fabric reinforced with continuous filament fiberglass versus a paving mat interlayer and the benefits of each in regards to tensile strength, crack-resilience, moisture protection, and overall life span of the pavement.

The recent earthquakes in New Zealand have highlighted the vulnerability and risk to life safety of some of the existing building stock across the country. It is important for New Zealand to satisfactorily address risk to life safety from earthquakes within the social, heritage, and economic context in order to develop an appropriate response to address this issue. For many years, New Zealand has had legislation providing for nationwide seismic assessment of existing buildings and minimum seismic retrofit levels in buildings. While the legislation historically has worked successfully in conjunction with recommended practice promulgated by the New Zealand Society of Earthquake Engineering for the seismic assessment and retrofit of buildings experience from the Canterbury earthquake sequence and other recent earthquakes has led to the need to reconsider some aspects of both the legislation and the guidance provided for engineers assessing and retrofitting buildings. This review has led to the questioning of some aspects of previous practice. In this paper, the authors briefly discuss the history relating to earthquake risk buildings in New Zealand, the issues that have arisen as a result of the earthquakes and the manner in which these are likely to be addressed. The paper discusses approaches being used in New Zealand to identify and assess large numbers of buildings throughout New Zealand. The concept of relating existing building seismic resistance/performance to new building standards is explored illustrating how structural engineers are engaging with building owners, policy makers and the general public to communicate seismic risk.

The seismic remediation of pre-Northridge steel moment-resisting frames has been primarily focused on resolving the lack of ductility of beam-column connections, with particular attention to the area between the beam bottom flange and column. In contrast, much less attention has been focused on possible problems with welded column splices of pre-Northridge moment-resisting frames. In fact, observation of column splice failures in seismic events has been infrequent. This paper will address potential column splice connection issues with two recently evaluated pre-Northridge steel moment frame structures, including a mid-rise and a high-rise example. The paper will focus on these main issues: existing evaluation and acceptance guidelines for pre-Northridge column splices, fracture mechanics considerations, column splice demand evaluation methodology, column splice weld specimen removal and testing, and splice weld remediation.

The Valley Transit Authority is working with the Bay Area Rapid Transit (BART) to ultimately expand BART’s existing light rail system south to San Jose. Several new stations are proposed as part of the Light Rail Track extension. However, two of the new stations will impact two existing large diameter water pipelines, owned by the Santa Clara Valley Water District. These existing lines have to be relocated away from the new stations. This paper will discuss the technical design aspects of installing new pipe and fittings into an existing 66” concrete pressure pipe raw water main and into an existing 42” steel pipe treated water main in order to properly relocate both lines. A key consideration in this modification to the existing lines is the thrust forces generated from the realignment. The thrust restraint of the old 66” line posed a number of challenges since the original pipe in this area did not have longitudinal thrust forces. Additionally the owner, the Santa Clara Valley Water District, has their own specialized thrust restraint procedure that is based on a 1960s paper. This approach is different than what is recommended by the American Water Works Association (AWWA) in the pertinent AWWA design manuals. Other challenges encountered during the relocation design included a number of pipe design considerations such as internal and external load, buckling, and fittings design. Further complicating the relocation effort is the need to account for a special “rattle box” casing to protect existing gas lines under a new “floating slab” for the Light Rail Track at one location. Included in the discussion will be recommendations on a few “lessons learned” from the relocation design efforts.

The City of Casselberry completed its $10.3 million asbestos cement (AC) pre-chlorinated potable water main pipe bursting project in April of 2014 which replaced approximately 35 miles of AC pipe. City staff has worked closely with the contractor, engineers and regulators from local and federal government to fully understand the applicability of the National Emissions Standards for Hazardous Air Pollutants (NESHAP) to pipe bursting of asbestos cement pipe. The Environmental Protection Agency and industry representatives have recognized the need to understand the potential environmental impacts of AC pipe rehabilitation and have tasked the Water Research Foundation and the Battelle Institute with studying the various methods of AC pipe rehabilitation. The environmental impacts of pipe bursting AC pipe have been analyzed with the Casselberry Water Quality Improvement Project as its pilot project. Results of the WRF study indicate that bursting AC pipe is more environmentally friendly than removing the existing AC pipe while providing the option to rehabilitate the existing pipeline in place. This paper will present the results of WRF Project #4465 while clearly describing how to burst AC pipelines and meet all existing regulations. This paper describes the challenges and successes of implementing a pipe bursting project, from field application of pipe bursting technology to working directly with regulators and rightof-way controllers who may be skeptical about pipe bursting AC pipe. A potential path forward through submission of a potential Administrator Approved Alternate to EPA that accepts a streamlined AC pipe bursting process is also presented.

As water pipelines and sewer force mains reach the end of their service life, leaks and uncontrolled line failures become more common. These failures may result in unacceptable environmental incidents and lack of adequate potable water and sewage service. This paper will discuss how hot tapping and plugging is used as an effective enabling procedure that allows the replacement or rerouting of concrete pressure water lines and sewer force mains while maintaining operations. The discussions in the paper will include: the tapping and plugging concept and sequence; engineering principals involved; forces developed in the application of the procedure and the need to address those forces with adequate thrust block designs. Two specific projects will serve as case studies to highlight the use of the technique. One case study is about the relocation and replacement of a prestressed concrete cylinder pipe sewer force main in an urban area. The other case study is the replacement of a municipal concrete pressure pipe (noncylinder) water supply pipeline. TAPPING AND PLUGGING ENABLES REPLACEMENT OF FAILING PIPE As water pipelines and sewer force mains reach the end of their service life, the frequency of leaks and uncontrolled line failures become more common. These failures may result in unacceptable environmental incidents and lack of adequate potable water and sewage service that create unsanitary conditions for system users. Hot tapping and plugging may be an effective enabling procedure that allows the replacement, repair or rerouting of concrete pressure water lines and sewer force mains while maintaining operations. When necessary for continued operations a temporary bypass line is installed to permit continuous flow during the repair or modification (Figure 1).

The Central Arizona Project (CAP) operates and maintains three (3) 21-foot diameter pre-stressed concrete non-cylinder pipes (PCP) as part of the aqueduct system that delivers almost 1,950 million gallons of Colorado River water per day, to Maricopa, Pinal, and Pima Counties in central and southern Arizona. The pipelines, installed in the late 1970’s, have experienced pre-stressing wire breaks and have been repaired several times since the early 1990’s. The wires have broken primarily due to defects in the wire. One of the pipes, the Centennial Wash Siphon, conveys water beneath Interstate-10 and the Centennial Wash, about 80 miles west of Phoenix, AZ. The siphon is upstream of CAP's first customer turnout, and as such is critical in the aqueduct's conveyance and delivery system. An internal electromagnetic inspection in January 2013 discovered several pieces of the pipe comprising the siphon had many broken prestressing wires, prompting a closer inspection and assessment of the siphon. The case study described herein examines inspections, assessment, monitoring, and subsequent repair using post-tension tendons of the Centennial Wash Siphon. This paper further discusses the ongoing efforts of monitoring, assessing, repairing, and maintenance practices for the largest prestressed concrete pipes in the world. A brief history of the siphons includes manufacturing of the 252-inch diameter prestressed concrete pipes, installation of the pipelines, and early investigations and repairs. The focus of this paper is on the assessment and monitoring since the last repairs in 2006, specifically newer technologies that have emerged to assist CAP in monitoring and making decisions in the repair methods and locations. Relevant points include a discussion on the excavation of the pipes requiring repair, the repair work (post-tension tendons), and maintenance practices. A brief discussion will follow on new technology recently installed in all three of CAP’s prestressed concrete siphons.

Being a relatively young industry in the US, the utility-scale wind industry has recently started to produce domestic design documents—standards and guidelines— to better coordinate requirements of the US building codes with the international (European) standards in dominant use throughout the wind industry. While wind farm tower structural analysis and design are becoming more and better documented, this paper will attempt to go yet further into unknown and undocumented tower structural engineering topics as encountered in daily practice. Examples of such topics with little or no treatment in the engineering literature include the causes and repairs of tower dents, flange gaps, and splice bolt fatigue failure. Also discussed are unresolved questions regarding mysterious out-of-round creep of tower sections and whether conventional transport methods could cause tower damage. This paper’s target audience includes stakeholders in the utility-scale wind energy industry, specifically: (1) structural design professionals; (2) project/construction managers; (3) plant operations and maintenance managers; (4) engineers involved in tower transport or erection; and (5) subsets of the aforementioned groups involved in code and standards development. This paper has the following learning outcomes: (1) to provide examples of typical tower damage and their repairs; (2) to provide a glimpse of tower structural engineering practice issues that are seldom documented in the industry literature; and (3) to describe unresolved issues as a first step for more industry discussion.

Removable compressive and distributive strand anchors were successfully used to anchor portions of the temporary support of excavation for the Hudson Yards development in Manhattan, New York. The removable strand anchors were implemented in lieu of conventional anchors to allow future excavation for a cut-and-cover tunnel and caissons. This paper describes the principles of removable compressive and distributive anchors, the installation and testing methods typically used, and the de-tensioning and removal procedures for the anchors. This paper also discusses lessons learned from the installation, testing, and removal of the anchors at Hudson Yards. The anchors used at Hudson Yards were bonded in bedrock. The findings from this study may prove useful to engineers considering the use of removable compressive and load distributive strand anchors for temporary support of excavation systems.

Bridge scour is the soil erosion caused by water flowing around bridge supports. Research has shown that scour has been the number one cause of bridge failure in the United States with an average annual rate of 22 bridges collapsing or being closed due to severe deformation. In this paper, the authors aimed to quantify the bridge scour risk in order to help people understand how risky the bridge scour is. The widely accepted definition of risk was adopted in the paper, the probability of failure times the value of the consequence. First, the New York State Department of Transportation (NYSDOT) Bridge Failure database and Florida Department of Transportation (FDOT) Unknown Foundation Bridges Database were used to quantify the bridge scour risk. Second, several other societal risks, including cancer, car accidents, and plane crashes, were analyzed to be comparable to bridge scour risk. Finally, the authors proposed the acceptable risk level, medium risk level, and unacceptable risk level in the United States based on the analyses in the paper. The outcome of this paper will aid people or authorities in understanding the risk of bridge failure as well as other society risks.

Many historic buildings from the late 19th and early 20th century have terra cotta roofs that are in need of repair or replacement, but their stewards find it difficult to mobilize financial resources for the full replacement of the terra cotta tiles. The application of fluid-applied waterproofing membranes on the exterior of the terra cotta tiles can extend the service life of historic terra cotta tiles and provide waterproofing protection for the building. Although these membranes are not “historic” material, if appropriately applied, they can provide a cost-effective and aesthetically appropriate alternate to full replacement of the terra cotta tiles. The selection of the appropriate fluid-applied waterproofing membrane requires a deliberate process that integrates both design and construction considerations. It includes background review to develop removal techniques (if an existing membrane is present) and options for the fluid-applied waterproofing membrane; a careful evaluation of the moisture content of the terra cotta; a field investigation that includes a series of mockups to understand the existing coating removal process and fluidapplied waterproofing membrane application process; and finally, careful installation and a continued review to ensure that all the lessons learned during the mockup (sample membrane installation) are implemented in the field. This paper presents practical advice to designers and builders to assist in the selection, design, and installation of fluid-applied waterproofing membranes on historic materials. Using a case study, the Luzerne County Courthouse in Wilkes-Barre, Pennsylvania, this paper shows the step by step process required to develop the design for the application of a fluid-applied waterproofing membrane over historic terra cotta. 1. THE PROJECT (BACKGROUND)

Forensic investigations of slip, trip, and fall incidents on stairs often involve the study of the applicable codes and standards that were in effect at the time of construction, at the time of subsequent renovation, and at the time of the incident. Similarly, the rehabilitation of existing stairs following a fire, flood, or collapse, as well as the change in building use, or change in occupancy, may prompt a similar study. Navigating the various editions of the codes and design parameters can be challenging. This paper aids in that effort. This paper surveys the Building Codes of the City of New York, its adopted reference standards, other related industry standards, and is a guide for navigating the historical editions and identifying the various provisions pertaining to the design parameters, such as illumination, signs, headroom, slip resistance, guards, handrails, doors, landings, and treads and risers, etc.

In 2013, Tacoma Water completed the robotic application of a semistructural polyurea liner in 2,168 lineal ft of 58-in. ID steel pipe installed in 1936 and repaired numerous times over the years to seal pin-hole leaks. Selection of a spray-applied, semistructural polyurea liner (defined by AWWA Manual M28 as a Class III semistructural liner) for rehabilitation of the pipeline on this project began in 2011 with the development of a business case evaluation (BCE), which compared the life-cycle cost and social/environmental impact of various rehabilitation methods to identify the least expensive and least disruptive option to seal leaks and extend the service life of the pipeline. The BCE included consideration of an option to continue repairing leaks until 2036 when the pipeline would be scheduled for replacement (i.e., the business-as-usual option); complete and immediate replacement of the pipeline with an equal size steel pipe with polyurethane coating and lining; slip-lining with a 54-in. OD HDPE pipe; spray-applied, semistructural polyurea liner; cured-in-place pipe; and cement-mortar lining. Although the Class III liner option was more expensive than the business-as-usual option, it was considerably less expensive than the replacement option and it made less of a social/environmental impact than either the business-as-usual option or replacement option. The other options considered did not meet technical requirements or were more expensive. This paper and presentation will cover the process used to evaluate pipe rehabilitation options and Class III liner pros and cons, polyurea material properties and testing, and application technology; review the performance of the lining application; and present the lessons learned from the first successful large-diameter, potable-water spray-applied, semistructural polyurea liner installation. Attendees at this presentation will acquire new knowledge about the advances in Class III liner design, polyurea material development, and robotic lining technology. Specifications, product literature, and industry partner information will be available for distribution. Spray-applied, semistructural liners created using specially developed polyureas applied with the proper equipment in the right conditions can certainly be considered as a cost-effective and low-impact option for the rehabilitation of large-diameter, potable-water pipelines. This paper and presentation will demonstrate that Tacoma Water is at the forefront of innovation and sustainability.

SECTION 1.0 The ductile iron pipe industry offers a variety of proprietary restrained joint products. (In this paper, the abbreviation PRDIP is used for proprietary restrained ductile iron pipe.) As with any product, optimum performance of PRDIP results when the manufacturer's installation instructions are followed. However, when these instructions are not followed, problems may result. Many miles of pipe were successfully installed for the project presented in this paper. At some vertical diversions, problems occurred where proprietary restrained joints were not fully extended. This paper is a generic investigation of a 36-inch (900mm) pressure pipeline project, but the information presented in Section 3 is based on an actual installation. One of the problem locations from that project is examined in detail. Vertical diversions in this project were particularly sensitive to the pipeline expansion that occurs if the PRDIP is not fully extended. Most designers and installers are aware of this issue and extend the joints whenever pipeline expansion would harm the pipeline or surrounding structures. Ductile iron pipe manufacturers have recommendations in their product literature for how this may be accomplished. To provide proper context, the paper begins by describing the issue. It then discusses in broad terms how the issue may be easily addressed and eliminated as a concern. DESIGN ISSUE, SECTION 2.0 A simple example will be used to introduce the issue, Figure 1. This issue is excessive slack that can accumulate in a pressure pipeline that uses proprietary restrained ductile iron pipe (PRDIP) in order to provide thrust restraint. It is important to note that slack in the joint may be desirable. The ability of a pipeline to extend and deflect may be advantageous for situations like long-term soil settlement. In other instances, accumulated joint extension can have adverse effects at a change in direction or a change in size.

This paper presents the results of a three year research program on carbon fiber reinforced polymer (CFRP) renewal of Prestressed Concrete Cylinder Pipe (PCCP) sponsored by Water Research Foundation to form the theoretical and experimental basis of an AWWA Standard being developed for the same purpose. The paper identifies limit states related to strength, stability, and watertightness of the CFRP liner considering continual degradations of the host pipe. The design is based on Load and Resistance Factor Design (LRFD) approach with load and resistance factors selected to ensure reliability comparable to those of other construction products, material adjustment factors that account for durability, and time effect factor that account for the sustained load effects. The experimental phase of the research program included full-scale three-edge bearing tests and hydrostatic pressure tests, and laboratory testing of shear bond strength and resin ductility. The theoretical bases of design are simple design equations the accuracy or conservatism of which is established through comparison with detailed finite-element analysis. 1. BACKGROUND Utilities have preempted the failure of distressed PCCP by replacement, external repair (post-tensioning with tendons or encasement), internal lining with steel or carbon fiber reinforced polymer (CFRP) composites bonded to the inner surface of the pipe. The use of CFRP for civil and structural applications began with university testing in the late 1980's, which validated its use for structural strengthening applications. In the early 1990's, CFRP gained acceptance within the engineering and construction industries through increased awareness and project applications, aided by the issuance of important approvals by Building Code agencies. In the late 1990s, CFRP was first used for repair of large diameter underground PCCP with the objective that it would be providing solely strength and water tightness as the PCCP continues to degrade with time. This is an application very distinct from the structural strengthening application of CFRP to beams and columns. In the early 2000s, various municipal utilities began the widespread use of CFRP lining for PCCP repair. In 2011, AWWA established a committee to draft a standard for the renewal

In the design of water pipe systems, bolted flange joints are usually given minor consideration in the overall scheme of things. Flanges have been successfully used in various types of pipe materials for over 100 years and their forms have been standardized for over 50 years. Most flange joint installations are completed without problem or concern, but when a complication arises, it can rapidly become a major issue for everyone involved. Most anomalies that arise during the service life of a flange joint are rarely due to erroneous design; they are almost always related to poor installation practices. This paper discusses installation issues that may occur with steel water pipe flanges, manufactured to AWWA C207 standards. Topics such as proper bolt and gasket selection, flange face arrangements, alignment during installation, bolt-up patterns and the relationship between applied bolt torque and achieved gasket stress are discussed, and practical recommendations are provided to avoid some of the common installation pitfalls. A comprehensive list of resources for the Practitioner is provided, along with a discussion of recent updates in various flange standards and guides. Water system owners, design engineers and installation contractors alike will benefit from the contents of this paper as a resource to achieve leak-free bolted connections on future projects.

1.0 ABSTRACT: The consequences of failure for Prestressed Concrete Cylinder Pipe (PCCP) are usually very high due to its large diameter and high internal pressure. To monitor these critical pipes, acoustic fiber optic (AFO) monitoring systems are now being used to observe the real-time breakage of prestressing wires in the pipe. However, if PCCP is not adequately prestressed, the wire break does not generate obvious acoustic noise that the AFO system is able to capture. The “un-recorded” wire breaks or inadequate prestress, together with other defects (such as corroded cylinder), can cause the failure of the pipe. This paper presents the results of an analysis conducted for a PCCP with inadequate prestress that failed without warning from the AFO system. The findings of this research will improve the current understandings of PCCP with inadequate prestress and help utilities better manage PCCPs with similar conditions. A 60-inch PCCP within the Washington Suburban Sanitary Commission (WSSC) jurisdiction failed without warning from the installed AFO system. This failure was unanticipated to because the number of broken wires recorded by AFO system was not severe enough to cause pipe failure under normal conditions. This failure also revealed the limitation of this technology in PCCP management, as the number of broken wires recorded is not enough to evaluate the pipe condition. Some other critical factors can also cause the failure of the pipe. Forensic investigations showed that the pipe had inadequate prestress in the failure area and that the water corroded the wires and cylinder which AFO system cannot detect. In this paper, a finite element (FE) model is developed to analyze the performance of the pipe with inadequate prestress in the prestressing wire. Scenarios such as prestressing wire with full prestress, no prestress, no prestressing wires, and with 6 broken wires are simulated to better understand the structural integrity of the pipe. The model considers loadings such as internal pressure, the weight of soil and pipe. It also considers pipe components such as concrete core, steel cylinder, prestressing wires, saddle steel, and mortar coating.

The Metropolitan Water District of Southern California (MWD) is a consortium of 26 cities and water districts that provides drinking water to nearly 19 million people in parts of Los Angeles, Orange, San Diego, Riverside, San Bernardino and Ventura counties. Metropolitan currently delivers an average of 1.7 billion gallons of water per day. Metropolitan has 830 miles of pipelines, of which 163 miles are Prestressed Concrete Cylinder Pipe (PCCP) lines. The lines are distributed throughout Metropolitan’s service area in both urban and rural areas. The pipelines range in diameter from 54 to 201 inches and operate at pressures up to 340 psi. Metropolitan’s PCCP was constructed between the early 1960’s through the mid1980’s. In 2000, Metropolitan initiated its PCCP assessment program. It included inspection of all 163 miles of PCCP lines using electromagnetic and visual inspection methods. Since that date, electromagnetic inspections have been performed annually during the winter shutdown season, with an average of 35 to 40 miles inspected every year. Every year the results of these electromagnetic inspections are reviewed and pipe considered to be at high risk of failure is repaired. A total of 7,534 feet of pipe or 378 pipe segments have been repaired since 1999 at a total cost of approximately $65 million dollars. Metropolitan has recently changed its asset management philosophy of PCCP from an inspection driven reactive method to a systematic replacement of its most at risk pipelines. This paper will discuss the first planned systematic replacement of one of its PCCP pipelines - the Second Lower Feeder. The Second Lower Feeder (SLF) has 29 miles of PCCP. The pipeline varies in diameter from 84 inches to 78 inches. This paper will discuss: the reasons for the change in philosophy of the asset management approach; the technical challenges faced by the project such as loss of hydraulic capacity; the approach to scheduling long shutdowns; prioritization and sequencing of the relining effort; and the various replacement options considered.

Steel pipe has long been designed for internal pressure with varying safety factors applied to the allowable design stress in the steel cylinder. Earth loads on rigid pipe were first developed in 1913 by Anson Marston and then modified by Marston and Merlin Spangler in the early 1930’s for flexible pipe. However, checking the steel water pipe for resistance to external loads was not common until the early 1960’s after Reynold Watkins corrected the original Iowa Formula (by Spangler) and the Modified Iowa Formula was published in 1958. This paper will discuss the use of the Modified Iowa Formula that is still utilized by many design engineers along with subsequent work that has been developed over the past 50 years and published. This subsequent work is based on measurable soil parameters that will be presented and discussed along with Steel Water Pipe serviceability levels against external loads. Background Mankind has been utilizing pipe and aqueducts to move water since approximately 2500 BC when the Chinese first delivered water through bamboo pipes. The Greeks were building aqueducts in 540 BC and then the famous Roman aqueducts of 100 to 300 AD were built. Iron pipe can trace its roots to the 15 century in Germany and the 17 century in France. Steel pipe was first used in the 19 century and concrete pressure pipe is a relatively young, 100 year old product. There is much less history of pipe design when compared to the history of pipe. The original design process, from the 19 century, was to simply have enough strength (thickness) to safely handle the internal pressure the pipe would contain. Folklore has it that Anson Marston, Director of the Iowa State College Engineering Experiment Station, was tired of getting stuck on muddy Iowa roads when the spring showers came every year. He decided that if they could drain the water off the roadways, similar to what railroads had been doing, the roads would be more passable. This led to the birth of external earth load calculations for rigid pipe in 1913 when Anson Marston and A. O. Anderson of Iowa State College published “The Theory of Loads on Pipes in Ditches, and Tests of Cement and Clay Drain Tile and Sewer Pipe”. In this work, the Marston formula for calculating loads on pipe in ditches was first published. The following equation was published as equation 2 in the paper: Eq. 1: W = CwB 712 Pipelines 2014: From Underground to the Forefront of Innovation and Sustainability © ASCE 2014

In this paper, analysis of risk of new glass reinforced plastic (GRP) panel failure during installation in sewers with the use of short relining technology, was investigated. Although past experience indicates that the assembly phase poses a significant risk of panel failure, structural analysis for this phase is usually not carried out at the design stage. The paper presents results of numerical analysis based on the author’s computational model for egg shaped panels which was carried out for the assembly phase. States of stresses and deformations were analyzed during grout distribution for different methods of protecting panels. The results of analysis allow for a more accurate selection of method for protecting GRP panels against failure during the assembly phase, which can reduce the risk of its occurrence and reduce the time and cost of renovation which will make this non-disruptive technology more competitive than traditional methods.

A soft ground arresting system (SGAS) is an alternative solution on airport runways where the runway safety area (RSA) does not meet international Federal Aviation Administration (FAA) standards. The length of the runway can be shortened if an SGAS is installed on both ends of the runway. This paper evaluates the options of using foamed concrete as the arresting bed material in an SGAS. Tests on the foamed concrete were conducted to see if it has the ability to withstand support vehicle loadings and fails underneath loading from an overrunning aircraft. The objective of the paper is to present the required and measured properties of foamed concrete (density, compressive strength and durability) and results of an evaluation into its possible implementation as an SGAS as an alternative to the engineered material arresting system (EMAS) on airport runways.

One of the predominant distress failure modes in Cement Treated Base (CTB) pavements currently in Zambia is reflective cracking that typically reflect through the bituminous or hotmix asphalt (HMA) surfacing layer. CTB materials are generally prone to shrinkage cracking and this is considered to be one of the primary sources of reflective cracking mechanism in CTB pavements. The perpetual and premature occurrence of this distress is an undesirable financial burden on the Zambian tax payers in terms of the costly road maintenance and rehabilitation activities that ought to be minimized. This paper is a theoretical and analytical discourse on the causes of this distress and recommendations for mitigation measures based on studies by different researchers world-wide. Remedial measures such as proper materials selection, optimizing mix designs, following proper construction, compaction, and curing practices, providing stress relief layers in the pavement structure, and delaying the final surface paving to facilitate adequate curing; micro-cracking have been reviewed and assessed for their potential applications to CTB pavements in Zambia. The paper then concludes with a recommendation of mitigation measures that are feasibility considered applicable to the Zambia CTB needs for subsequent implementation by the Road Development Agency.

Many buildings located in industrial and petrochemical facilities require protection from accidental external explosions. Due to the difference in basic characteristics of the two loading types, design of these buildings to resist external explosions or blast loading poses significant challenges when the facility is located in in a region with high seismicity. Seismic loads are cyclic, inertial loads with long durations, whereas blast loads are short duration impulse loads. Seismic loads are defined by ground acceleration response spectra while blast loads are specified by blast overpressures and durations. In blast-resistant design, building owners determine hazard return periods and acceptable performance and damage levels based on risk evaluation of personnel safety and property loss. Current seismic code provisions have been developed with the intent of achieving performance through prevention of building collapse and protection of life safety. Next-generation, performance-based seismic design will be based on performance and damage levels similar to those used in blast resistant building design. For purposes of demonstrating an optimized design process for both seismic and blast loading using performance-based design philosophy, this paper presents a blast-resistant design of a reinforced concrete building in a petrochemical facility located in a region with high seismicity. Selection of effective structural systems, performance levels, acceptable damage levels, structural modeling, structural analysis methods and ductile design and detailing of structural components are discussed in this paper.

On May 3, 1999, an F5 tornado struck Moore, Oklahoma causing loss of life and destruction of property. On May 8, 2003, an F4 tornado struck Moore, Oklahoma. On May 20, 2013, Moore was struck by an EF-5 tornado, with a similar path to the 1999 and 2003 twisters. This paper will compare our observations of damage caused by the 2013 tornado event to the damage documented by available sources during the 1999 and 2003 outbreaks. This paper will also review the history of the local building codes and ordinances and discuss their impact on the damage observed. The scope will include a summary of case studies of detailed damage evaluations in which construction defects and code variations may have contributed to the observed damage. Rimkus Consulting Group, Inc., 7510 South Quincy Street, Suite 160, Willowbrook, IL 60527, PH (630) 321-1846, Email: vffratin@rimkus.com Rimkus Consulting Group, Inc., 5251 West 116th Place, Suite 200, Leawood, KS 66211, PH (913) 549-2123, Email: saschroe@rimkus.com

Historic masonry arch bridges were not designed to perform under the load levels typical of modern vehicles. Most of them still perform well due to their inherent strength; others experience various forms of distress. Load rating is the standard approach to assess the capacity of these structures; however, predicting the capacity of an arch bridge is difficult because of the complex behavior of the structure. Mathematical models are powerful tools to predict the actual performance of the structure, but they rely heavily on the accuracy of information provided by field investigations and engineering assumptions. Preservation and rehabilitation of these structures depend on both the success of in situ experimental investigations and numerical analysis. In this paper, a pragmatic approach to assess historic masonry arch bridges is described. The use of nondestructive evaluation (NDE) techniques to assess the existing condition of the structure is briefly discussed. The paper focuses on the load rating procedure provided by the American Association of State Highway and Transportation Officials (AASHTO) Manual for Bridge Evaluation (MBE) (AASHTO 2011). This method is reviewed based on results from a Finite Element Analysis (FEA) and diagnostic load test of a two-span masonry arch bridge over the Pascoag River in Burrillville, Rhode Island. The influence of the analysis assumptions on the bridge rating is evaluated with the aim of providing recommendations on how to improve the accuracy of the AASHTO load rating procedure for masonry arch bridges.

North America has an aging fleet of coal plants which contain substantial ductwork systems. This ductwork is exposed to harsh conditions associated with plant operations and environmental conditions. These harsh conditions increase risk of metallurgical deterioration over time. This paper will discuss the effects of high temperature operations and the resulting graphitization effects within ductwork. Graphitization is the breakdown of the material’s metallurgical microstructure, thus forming a weakened failure path. There have been documented failures in coal fired power plants due to graphitization which have caused plant shutdowns and injuries to personnel. Currently, there is no industry consensus document providing information on the formation of graphitization and how to combat this problem. Multiple individual reports and technical papers on graphitization and its effects have been written in the past 50 years, the formation of a single source document outlining guides and standards would be beneficial to the power industry. The primary goal of this report will be to condense the relevant industry information on this topic into a summary, discussing the formation characteristics of graphitization. Additionally, the report will provide technical information on the graphitization process including critical components, design considerations, and inspection and remediation methods to correct possible existing conditions. Through research of top industry documents, it has been concluded that the effects of graphitization need to be closely considered and monitored as temperatures exceed 800⁰F. Temperatures below 800⁰F may experience graphitization, but at such a marginal rate that it can be neglected over the design service life. By providing a single location outlining the formation characteristics of graphitization, engineers will benefit from standardized procedures for the inspection, analysis and design of existing and new hot-side ductwork components, thus, yielding improved consistency and product quality.

Highway lifelines would suffer different levels and types of damage when major natural disasters happen, which would influence traffic and reduce highway reliability. This paper focused on highway damage, traffic impact, and connection reliability. The author analyzed the failure modes of the highway traffic lifeline during major natural disasters in China, studied the influence of highway damage on traffic, and put forward the definition of traffic function loss of highway traffic lifeline. And according to the difference of traffic function loss under various kinds of highway damages, the traffic function loss types were raised. Then, the traffic function loss was classified into four grades based on traffic function loss degree. Finally, the correlativity between traffic function loss and connected reliability of highway lifeline was established. The paper considered the influence of highway damage on connected reliability from the perspective of traffic function loss, and the research results would provide new ideas for connected reliability analysis of highway lifeline during major natural disasters.

With more than 10,000 entries of traffic accident data as the basis of study, this paper introduced Direct Property Loss and categorized Roadway Severity as a dependent variable. Predicated on previous correlation studies of objective factors and traffic accident severity, subjective driver factors were put forward in this paper, including driving experience index, driver's age, and accident responsibility, etc. Fifteen evaluation indicators were brought in to develop a traffic accident severity model based on multinomial logistic, of which seven were used after independent variables of weak correlation were singled out from a correlation analysis of independent variables. Tests of model's feasibility were conducted and passed, suggesting that subjective factors such as driving experience, age, and accident responsibility are in significant correlation with the severity of traffic accidents.

With the frequent occurrence of pipe-failure accidents of urban water mains and the increasing application of trenchless rehabilitation technology in municipal pipeline systems, this paper focuses on a crucial matter of the trenchless rehabilitation of urban water mains: lining design. Rational design of linings plays a significant role in a certain trenchless pipe rehabilitation engineering, which is directly related to the final structural strength of the rehabilitated pipe system, the flowing capacity of the rehabilitated pipe and the final cost of the project. As water mains are pressure pipes and complicated pressure waves may occur in the running period, the lining design of water mains is quite different from the pipes which mainly withstand external pressure. However, the existing lining design theory mainly concerns external pressure, seldom concerning internal pressure. So this paper tries to establish a set of new lining design methods for the rehabilitation of water mains, concerning external pressure as well as internal pressure waves. Based on the summary of the existing lining design theories, the lining design methods in this paper are established through mechanical analysis of the conditions of pipe loads and the strength of the rehabilitated water mains resisting inner and outer loads. Through a series of mechanical analysis and references of existing lining design theories and related mechanical models, this paper finally provides a set of relatively effective lining design methods for different trenchless rehabilitation techniques using in water mains. The study in this paper will offer references for the future trenchless rehabilitation of urban water mains.

The leakage of high-pressure natural gas pipeline can lead to serious accidents and pose a significant threat to people and buildings in the vicinity of the failure location. This paper examines the harm effect distances of different consequences based on harmful criteria. And possible consequences caused by pipeline leakage are assumed and their subsequent harm effect distances are computed using the software EFFECTS. Harm effect distances evaluation was performed considering jet fire and vapor cloud explosion (VCE) as the worst-case scenarios. Results show that for pipeline leakage, the jet fire produces longer harm effect distances, so the jet fire scenario should be considered as the limiter for harm effect distances evaluation. Based on the analysis of this paper, harm effect distances caused by the leakage of a high-pressure natural gas pipeline can be evaluated, which will not only be useful to prevent and control natural gas pipeline leakage accidents, but also provide a good reference to design of new constructed pipelines.

Trenchless pipe replacement, which involves pipe bursting, is a construction method used for replacing existing and deteriorated underground pipelines with a totally new pipe of equal or greater diameter. It is a sustainable and cost-efficient pipeline replacement method compared with the conventional open trench activities which can result in noise, traffic disruptions, environmental impacts etc. In recent years, the use of trenchless pipe replacement has grown significantly in China. This paper provides discussion on several key technical problems in pipe bursting operations including ground displacement, soil conditions, scratches on new pipe and pull force analysis. The results from this work should help pipeline managers and engineers in planning successful pipe bursting and assessing risk. To gain some insight into the pipe bursting, this paper introduces the basic mechanism and installation procedure of this trenchless process.

It is very dangerous for the safety of the pipeline which crossing the complex place where the geological disasters occurred frequently in the rainy season or by the influence of floods. Therefore, the mechanical response analysis of the pipeline which is influenced by the floods is essential. According to the actual stress state in the pipeline project and the relationship with the surrounding soil, this paper study and build the corresponding static and quasi-static response analytically format. Some specific examples were calculated and analyzed by the strain-based safety assessment criteria, and the most dangerous point was identified. The influence law of different diameters, internal pressure and the material of the pipeline to the pipe-stress was investigated. The results show that the mechanical model which was established in this paper is coincide with the actual deflection and the analysis of the stress. And the change of the diameter of the pipe is the most sensitive factor to the stress of the pipe which is influenced by the floods.

This paper reviews the seismic design performed for the replacement of a 373-meter-long (1,224-foot-long) naval wharf located in Apra Harbor in the U.S. Territory of Guam. Design challenges included in the paper are associated with eliminating the interference between the structural components of the new and existing walls, accommodating the uneven alignment of the existing wall, and incorporating the limited soil improvement possible at the corner region. The existing wall, constructed originally in 1948, consists of a sheet pile wall anchored to a sheet pile tieback wall. The wharf has not been in use since 1993 because of the significant damage it suffered after the magnitude 8.0 earthquake. Extensive liquefaction was deemed the main reason for the structural damage observed. The replacement wharf, currently under construction way, consists of a new anchored sheet pile wall outboard of the existing face of the wall while leaving the existing structure in place. The new structure includes soil improvement behind the sheet pile wall to mitigate the effects of probable liquefaction during future seismic events.

This paper discusses the devastating effects of tsunamis on the Crescent City Harbor District's marina and the District's efforts to recover from the tsunami and replace the marina with a new tsunami resistant marina. The main marina in the harbor at Crescent City, California was badly damaged by a tsunami in 2006. Rather than simply rush to "put back the marina the way it was," the District elected to design a replacement harbor to be as tsunami resistant as feasible. While the design process was underway, the March 2011 tsunami struck the harbor, hurt the fishing industry and threatened the local economy. The 2006 and 2011 tsunamis caused about $50 million damage to the waterfront structures and navigable waterways at Crescent City. The local fishing community marina was severely damaged and required replacement. The occurrence of two tsunamis so close together in time illustrates the importance of including tsunami effects on the design of this marina. Marinas are historically designed to resist operational vessel loads due to berthing, wind, wave, and current. The Crescent City marina is the first marina designed specifically to resist a significant tsunami wave. The author and his colleagues discuss the harbor damage from tsunamis, the emergency response plan, the design approach for the replacement marina and rock slope protection, the regulatory, permitting, and anticipated construction issues. The design process includes geotechnical constraints, hydrodynamic analyses, and float and pile design. This paper also discusses the cost effective means to optimize float and pile design, improve the recovery time for future tsunami damage, tsunami design lessons learned, and a path forward for future marina tsunami design. BACKGROUND Crescent City is located in northern California near the Oregon state border. The port had its beginnings in 1855, with the first wharf built on Whaler Island followed by initial construction of the Outer Breakwater by the Corps of Engineers in 1920 and the Inner Harbor and Marina in 1972. Commercial and sport fishing boats operate out

On March 11, 2011, the largest earthquake ever recorded in Japan struck off the coast of the Tohoku region of the country, immediately followed by the one of the largest tsunamis ever recorded. Following these devastating events, the American Society of Civil Engineers (ASCE) and its Coasts, Oceans, Ports, and Rivers Institute (COPRI) committed to send multiple teams to Japan to investigate the performance of port and coastal structures. This paper summarizes the findings of the northern Port and Harbor team, whose final report is in publication and expected to be released in 2013 [COPRI, 2013]. The northern team investigated over 14 major port facilities along approximately 300 km of coastline. The team visited Japan in May 2011, focusing on sites north of Fukushima. The COPRI team partnered with the Japanese Ports and Airport Research Institute (PARI) and greatly benefited from collaboration with PARI port specialists in the field. While on site, the team documented observable damage and met with facility personnel, eyewitnesses, researchers, and government officials. This paper includes a brief summary of findings as well as recommendations appropriate for the ports community. The primary purpose of the team was to assess and learn from the performance of port infrastructure, including waterfront, storage, protective structures, handling equipment, process systems, and utilities. This investigation focused on design, construction, and performance with an emphasis on the lessons learned from both failures and successes. Topics addressed include structural performance, code efficacy, ancillary equipment performance, tsunami prediction and life safety, early warning systems, as well as recommendations for high tsunami risk ports and future research, all of which are directly applicable to United States facilities. Generally, port and harbor structures were found to have performed well, with few catastrophic failures observed. Pile-supported and gravity wall structures generally performed with minimal damage. However, damage to electrical supply systems and damaged or lost equipment associated with tsunami inundation delayed restoration of full operations for many port facilities in the region. Significant loss of life was found to occur where predicted or design inundations resulted in vertical evacuation heights or seawall protection heights that were not sufficient.

This paper provides an overview of the unique approach taken by a multi-discipline team consisting of Washington State Ferries (WSF) personnel, structural and geotechnical engineers, and economists to perform a risk assessment of a portion of WSF's aging timber trestle inventory. The intent of the assessment was to establish the cost-effectiveness of trestle replacement compared to refurbishment by quantifying risk for a range of seismic events and incorporating that risk into WSF's Asset Management Model. Failure scenarios developed using site-specific characteristics - such as trestle condition and site seismicity - were coupled with life cycle cost modeling techniques to assess the risks associated with doing nothing, refurbishing the existing trestles, or completely replacing the trestles at seven ferry terminals. This paper describes the approach developed to create an economic model and evaluate the efficacy of trestle upgrade and replacement options. A case study of the trestle at the Vashon Island terminal is included to demonstrate direct implementation of the approach and the results obtained.