Journal of Performance of Constructed Facilities

On October 23, 2011, a destructive earthquake of $M_{\mathrm{w}}=7.1$ occurred in Eastern Turkey. The event occurred on a previously unknown fault with a thrust mechanism and resulted in 604 deaths and major structural damage to the buildings. The highways at the Van earthquake zone were open to service of rescue operations, aid trucks, and regular traffic immediately after the devastating event. As a success story, the bridges closer to the fault line than the towns of Van and Erciş were observed to have minimal damage, such as minor support movements and cracks at the shear keys. Among the 14 highway bridges in the region evaluated by the authors, only two adjacent bridges, Bendimahi-II, had minor structural cracking along the column height. As expected, the bridges of concern were observed to perform in the essentially elastic state. The main focus of this study was to evaluate the seismic bridge design practice in Turkey, which resulted in a successful seismic performance of the earthquake-zone bridges. As an illustrative example, Bendimahi-II bridge, the closest one to the fault line, was studied through an analytical investigation.

Damage and performance of railway bridge structures during the 2011 Tōhoku Earthquake are reported. Although the scale of the earthquake was historically the largest known, seismic damage to structures was smaller and less time was required for recovery of service compared with an earlier major earthquake. Upgrading of seismic code and planned seismic retrofits performed after the 1995 Kobe Earthquake were found effective for reducing seismic damage to bridges and civil structures; damage to bridge superstructure, with complex geometry and damage to secondary structural systems such as electric-power poles, now became the prominent type. Enormous structural damage observed for areas affected by severe tsunami forces (which had offered great challenge to structural engineering) is also reported. Following this, bridge performance (under the force of the 2011 Tōhoku earthquake and subsequent tsunami) is studied using data recorded by monitoring systems installed on bridges that were located in strong motion areas. Based on this experience, advantages of and challenges to the structural health monitoring system are also discussed.

The performance of road bridges undergoing liquefaction in the foundation soils and substantial lateral spreading during the 2010–2011 Christchurch earthquakes is discussed in this paper. Three, well-documented case studies are presented in detail to illustrate the performance of bridges and their typical damage associated with lateral spreading. The short-span bridges on pile foundations have a very stiff superstructure (deck), which was a key factor in the seismic response of the bridges. It led to a characteristic deformation mechanism for all bridges involving lateral spreading-deck pinning-abutment backrotation with consequent damage to the abutment piles and slumping of the approaches. Overall, road bridges performed relatively well in the 2010–2011 earthquakes compared to other engineering structures, despite the high seismic demands including substantial liquefaction and large kinematic and inertial loads due to spreading and strong ground shaking, respectively.

This paper presents the observed bridges performance, including damage attributed to storm surge, wind, impact by debris and barges, and scour from Hurricane Katrina, and study of wave forces on bridge decks, including a recommended simple estimation method and countermeasures used to restore functionality to the bridges and transportation system. The lessons learned and research studies of the storm surges and mitigation measures performed directly by the Federal Highway Administration (FHWA) and state DOTs through the National Cooperative Highway Research Program are also briefly introduced.

This paper presents a case study on monitoring bridge performance under an extreme rainfall event, Typhoon Morakot, which invaded Taiwan on August 8, 2009. An advanced monitoring system was designed in an attempt to improve the efficiency of performance monitoring of bridge substructures during natural hazards by synchronizing various instrumentations, including accelerometers and inclinometers. It successfully recorded the performance of the Shi-Tzou Bridge during Morakot. Progress of this study provides not only verification of the developed intelligent monitoring system but also of the valuable performance data for engineers to access bridge performance under scour and floods conditions.

The exposure of pier foundations owing to scour significantly reduces the foundation-bearing capacity and diminishes the flood-resistant capacity of a bridge. This paper proposes a nonlinear quasi-static analysis procedure for the performance of bridges with pile foundations under flow-induced loads for the evaluation on the flood-resistant capacity of scoured bridges. The Winkler beam model is adopted for the modeling of the pile-soil system, and the distributed hinge model is utilized to simulate the possible flexural failure of the piles. Soil springs with nonlinear $p\text{-}y$ curves are used to represent the nonlinearity of the supporting soil. To demonstrate this procedure, a case study on the Shuang-Yuan Bridge in Taiwan was performed for various flood and scour conditions. This bridge was partially demolished in a major flood event caused by Typhoon Morakot in 2009. According to the analysis results, a possible scenario for the failure of the Shuang-Yuan Bridge is presented, and the proposed method is shown to give a reasonable assessment of the flood-resistant capacity of bridges with scoured pile foundations.

In Taiwan, many bridges span rivers that exhibit severe channel variations in response to drastically increased flows and resulting floods caused by typhoons and storms. Flood-induced scour can undermine the effective embedment depth of bridge foundations. The Shuang-Yuan Bridge, spanning a downstream section of the Kaoping Stream, was severely damaged during Typhoon Morakot in August 2009. A qualitative investigation was conducted to determine the possible causes of this bridge collapse. Relevant hydrologic, meteorologic, structural, geotechnical, and terrain information from various sources both in written and image formats was collected, updated, and reviewed. The disaster investigation included field investigations, nondestructive inspection of bridge remnants, and investigation of structural damage of upstream river crossings, hydrologic changes, damage to training structures/embankment, riverbed profile changes, and debris during the flood event. Several inspections were applied to determine the embedment depths, positions of underwater remnants, and changes in riverbed elevation. The investigation results identified multiple possible causes of failure, including flood flows, river-bend-induced turbulent flows, and the joint effects of extended foundations and rafted wood.

The failure of the Shuang-Yuan Bridge in Taiwan caused by floods associated with Typhoon Morakot in August 2009 prompted this forensic investigation into its causes. The investigation found multiple factors for the bridge failure: (1) flood flows, (2) river-bend-induced skewed flow, and (3) the effects induced by extended foundation caps and rafted woody debris. A qualitative assessment framework, which includes hydraulic computation, a fluid-solid-coupled model, and foundation stability analysis, is introduced to develop scenario simulations and forensic diagnosis to identify the main causes of the bridge failure. The watershed-wide and local hydraulic conditions are reconstructed using hydraulic computation. The flow field, dynamic water-pressure distributions, scour formation, flood resistance, and flood thrust are efficiently simulated using a fluid-solid-coupled model and foundation stability analysis around the bridge foundations under different hydraulic and environmental conditions. The forensic diagnosis results show that river flooding, extended foundations, skewed flow, and rafted wood aggravated the scour depths and undermined the flood-resistant capacity of the bridge at different severities. In particular, rafted wood contributed to individual fracturing of the bridge piles.

Recent large earthquakes in China (e.g., Wenchuan earthquake and Yushu earthquake) resulted in enormous damage to school buildings and took many students’ lives. Recognizing the seismic vulnerability of existing school buildings, the Chinese government started a nationwide mission in 2009, aiming at increasing the seismic capacity of school buildings through inspection and retrofit activities. This paper presents the experiences of the authors in the retrofits of school buildings in which seismic isolation by using rubber and/or sliding bearings was adopted as a new and efficient retrofit technique, as compared with conventional ones. The retrofitted school buildings include masonry buildings, RC frame buildings, and a mixture of both. Design methods and the corresponding requirements in the modified seismic design code are presented, and typical construction procedures of the seismic retrofit are summarized from an engineer’s point of view. Procedures regarding the contract and review of the retrofit projects are also introduced. To this end, a case study is made to demonstrate the proposed design and construction methods. The presented work provides references to the seismic retrofit of existing buildings.

Concentrically braced frames (CBFs) are broadly used as lateral-load resisting systems in buildings throughout the United States. Current state-of-the-practice is the use of special concentrically braced frames (SCBFs) where ductility under seismic loading is necessary. Prior to modern seismic codes, braced frames were designed without ductile detailing. Here these systems are termed nonseismic braced frames (NCBFs), which are essentially CBFs designed with no special detailing requirements. These may comply with older code requirements in high-seismicity regions or current code requirements in low-seismicity regions. Many are still in service throughout the United States. Prior research has focused on SCBFs, which has improved their seismic performance. In comparison, there is significant uncertainty regarding the seismic performance of NCBFs and they may be vulnerable to collapse. A study was conducted to evaluate this vulnerability. At the start, a pilot experimental test of NCBFs was conducted. These results were combined with prior analytical models developed for SCBFs to develop a preliminary model of NCBFs. The model was then used to evaluate seismic performance of an NCBF system and compare these results to an SCBF system. A 3-story prototype building was the vehicle for this comparison. The results show there is a significant seismic vulnerability and uncertainty associated with these structures, and they represent an unstudied significant seismic hazard in the United States.

The joint behavior of snow and wind actions on structures becomes relevant for design in many regions of North America. With trends toward performance-based design for loads/actions arising from natural hazards, information is needed on both individual and joint hazards, e.g., at different hazard levels, exceedance probabilities, or mean recurrence intervals. The writers have developed one approach for two hazards that can be well modeled by sparse processes and have also developed recommendations for joint hazard characterization for the case of a full (e.g., 50 years) design life. The present paper shows how these findings can be extended to provide useful information for joint hazard characterization in shorter reference periods. This can be useful, for example, in the design (single or multiobjective) of formwork or other temporary structures in high wind/snow regions.

Accelerated bridge construction (ABC) is gaining momentum as the bridge community is educated on the latest technologies and structural systems that can be implemented under the umbrella of ABC through workshops and demonstration projects. Further, ABC is promoted through various resources provided by the Federal Highway Administration (FHWA) and the Every Day Counts Initiative that recommends implementation of some form of acceleration into every bridge project. The ultimate goal is to make ABC a common practice. Hence, detailed documentation of challenges and lessons learned from previous ABC projects is vital for effective and efficient application of future ABC projects. This paper presents the first full-depth deck-panel ABC project in Michigan with details on the bridge configuration, strengths and limitations of the special provisions, observations during bridge construction, the project team’s timely decisions to overcome some of the constructability challenges, and lessons learned during implementation. Although the information presented in this paper is related to a specific project, the recommendations are applicable to other bridge types with prefabricated bridge elements and systems (PBES) to achieve the ABC objectives.

A live-load test and a three-dimensional (3D) finite-element (FE) model of a three-span continuous prestressed–concrete girder bridge are described in this paper. The precast prestressed-concrete simple-span girders are made continuous by pouring a continuity diaphragm between the girders ends. Special reinforcement is extended from the girders’ bottom flanges into the diaphragm to ensure continuity under positive moments that result from time-dependent effects such as creep, shrinkage, and temperature gradient. This detail was adopted in a recently constructed bridge. The bridge has been instrumented with embedded and surface-mounted sensors and was monitored for over 2 years to evaluate the performance of the new continuity detail. A live-load test was carried out to evaluate the response of the new detail under truck loads. Field test data were used to validate a 3D FE model that was developed for the entire monitored segment. Once the FE model was validated, it was used to investigate the efficiency of the detail in transferring loads between adjacent girders. From the FE results, it has been found that the continuity index is approximately 88%.

The time required for building bridge abutments is one of the main obstacles facing rapid bridge construction. For typical span bridges, this can be remedied by using controlled low-strength materials (CLSM) as backfill materials placed behind full-height, precast concrete panels that are integrated with the CLSM backfill via steel anchors. The CLSM bridge abutments can be constructed in a short time as they require neither heavy machinery for excavation and compaction nor piling equipment. In addition to the speedy construction, the ability to use by-product material, such as fly ash and foundry sand, in CLSM backfill translates into greater economy and the potential for a sustainable design. This paper describes the behavior of an instrumented laboratory, large-scale CLSM bridge abutment with full-height, precast concrete panels that was subjected to a monotonically increasing sill pressure. The experiment showed that the CLSM bridge abutment is capable of carrying typical bridge loads with a large safety margin and with negligible deformations.

This investigation presents results of the statistical and probabilistic analyses of 3,269 normal weight concrete cylinder compression tests used for recently constructed highway bridges in California. A new model for in-place strength of concrete structures is proposed as a function of the specified compressive strength, the normalized 28-day cylinder strength, and age of the structure based on a realistic strength–age relation for hardened concrete. The model prediction indicates that concretes in cast-in-place bridge structures designed with specified compressive strengths of 25 MPa (3.6 ksi), 28 MPa (4.0 ksi), and 35 MPa (5.0 ksi) reach their maximum strengths at about 40 years, with approximately 98% of the maximum strength occurring during the first 10 years. Also, through significance testing on the 28-day cylinder strengths, it was established that the California Department of Transportation practice of using an expected concrete strength instead of the specified strength for seismic design of bridge components is justified. An expression for predicting the 28-day strength of concrete cylinders as a function of the strength of companion cylinders, also proposed herein, could prove a useful tool for quality control of concrete during construction.

This paper demonstrates the analysis of the deterioration trends of bridges to evaluate the operational structural performances of the various kinds of bridge construction materials and/or structural designs. The goal of this study is to improve the performance of structural materials used to construct bridges, based on rigorous population-based analysis of the performance of those materials in service. The analysis uses the raw database of the entire National Bridge Inventory in the United States and derives material deterioration aspects at the serviceability limit states. The study develops measures of deterioration to consider the trends in the accumulation of structural deficiency versus service life cycle by material. The approach defines the criteria of rate and pattern performances to analyze the comparative deterioration trends. A multiple-criteria diagnostic approach determines the overall equivalent structural performances integrating the rate and pattern performances with the measures of condition, durability, and longevity. The national network-level operational experience by categorical deterioration trends produces the most comprehensive comparative basis of structural performance of bridge materials. Overall for all bridges, the average increase of structural deficiency is 0.51%/year, adding to the already existing 12.35% and consisting of an average annual increase of structurally deficient bridges by 4.10%. The accumulation of structurally deficient bridges begins only after 10 years for most materials. The rate and pattern performances of almost all of the materials are quite poor. Thus, the equivalent performances integrating the deterioration trends are lower. The results provide a more objective indication and comparison of structural performances under the actual circumstances and help predict future performance. The approach supports the development of improvements necessary to increase the relative performances of distinct bridge materials for more sustainable service.

This paper introduces a comprehensive full-scale pile load test program on 457-mm (18-in.) square prestressed concrete (PSC) piles in Savannah, Georgia. The program consisted of pile driving analyzer testing during initial pile driving and restrikes, Statnamic tests, static axial compression load tests, and reciprocal lateral load tests. On the basis of the interpretation of the test data, some important findings were obtained: (1) the alluvial clays in Savannah can only provide very limited resistance; (2) the time-dependent pile capacity gain after pile driving (i.e., setup effect) was approximately proportional to the pile embedment length into the Marl formation; (3) the estimated equivalent static pile capacities from the Statnamic tests were comparable to those from the static axial load tests; (4) the Marl formation is a competent bearing stratum for piles; (5) the potential degradation of pile concrete stiffness caused by pile driving should be accounted for in pile capacity analysis; and (6) the piles exhibited stiffer response under the monotonic lateral loading condition than the cyclic lateral loading condition. Finally, predictions on both axial and lateral pile capacities, using the soil parameters derived from the instrumentation data and back-analysis of the pile load tests, were compared with the corresponding pile load test results. The comparisons demonstrate that in combination of the static-bearing capacity formulas and the LPILE program, the developed soil models can make reliable predictions on both the vertical and lateral behaviors of the PSC piles driven through the soft alluvial clays to end bearing in the Marl formation.

This paper presents a standard data structure for predicting the remaining physical life and consequence of failure of water pipes. Correlating the various pipe material types with the pipe life cycle, failure modes and mechanisms are crucial in defining the various parameters that affect water pipelines. Identifying and estimating the failure consequences of a pipeline are also important for risk management. A complete understanding of the pipe life cycle, failure modes and mechanisms, standard data structure to support predictive modeling, and failure consequences can be effectively combined to aid in advanced asset management of drinking water pipelines.