Journal of Performance of Constructed Facilities

In a Latin American context, few studies exist regarding the construction of churches during the colonial period using adobe and rammed-earth techniques. Investigations of their spatial characteristics, systems of construction, and structural behavior, therefore, are also scarce. This lack of research has led to poor results in restoration attempts for these kinds of churches, which has caused the loss of important Colombian architectural and historical heritage. Additionally, Colombia is at a high seismic risk, and adobe and rammed-earth buildings are particularly vulnerable during earthquakes. This paper presents the results of an investigation of these kinds of structures, developed by the investigative groups investigation group on materials and structures (GRIME) and Estructuras & Construcción (at Pontificia Universidad Javeriana) during the period 2002–2013. The investigation focuses on churches in the geographical area within the central Colombian highlands built during the 16th and 17th centuries. The study takes an architectural and historical approach coupled with structural laboratory work (involving shake table tests on 1:50 models), where the authors applied a reinforcement alternative with confinement wood elements to improve the seismic performance of the structural system of rammed-earth churches. According to these results, the use of confining wood elements as reinforcements reduces the relative displacement induced by earthquakes to doctrinal earth-built churches and diminishes the propagation of cracks.

The constructed cost of conventional noise walls is about $2 million per linear mile. In many areas, the cost-effectiveness criteria of $25,000 per benefited receiver are exceeded so that these areas are not eligible for federal-aid funding for noise abatement. Consequently, the residents in these areas are dissatisfied that no noise reduction measures are provided to them. To address these issues, the Indiana Department of Transportation evaluated the line of sight (LOS) wall to improve customer satisfaction at a less expensive cost. Three different LOS walls were installed and compared with the conventional concrete noise wall. Such information will be useful to state departments of transportation not only to develop specifications for LOS walls, but also to upgrade their traffic noise policy to improve customer services.

Expansive soil is one of the most common causes of pavement distress. Expansive soils undergo changes in volume due to moisture fluctuations from seasonal variations. These changes are reflected in the stability and performance of pavement layers. The objective of this research is to evaluate existing repair projects on selected farm-to-market (FM) roadways. Those roadways experienced failures in the form of fatigue and rutting along the wheel path, and longitudinal (faulted) cracking, including edge cracking. Those failures are due to high-plasticity expansive soil and narrow pavement lanes. This research study implemented visual survey, field and laboratory testing, ground penetrating radar (GPR) scanning, and structural design evaluations for three project sites to evaluate existing pavement treatment options. Using up to 14 years of performance records, this study suggested that geogrid reinforcement combined with lime-treatment is an effective repair at areas with low to moderate plasticity soil. Also, cement-treated base is found to be an effective treatment option in areas with high-plasticity expansive soil.

This paper investigates the evaluation procedure of an AASHTO Type 3 precast-prestressed girder that was extensively damaged by truck impact and then repaired using externally bonded fiber-reinforced polymer (FRP) composites. Results of this study can be applied to bridges having similar vehicle impact incidents. Parameters whose effects were investigated on the evaluation procedure include (1) the effect of horizontal resistance of elastomeric bearing supports, (2) the presence of barrier wall and sidewalk, and (3) live load distribution factors obtained from finite-element analysis (FEA) compared with the simplified method prescribed by other codes. FEA showed that support horizontal resistance has negligible effects on live load distribution factors for shear, $F_v$, while it has considerable effect on live load distribution factors for moment, $F_m$. The live load distribution factors $F_m$ and $F_v$ calculated from the simplified method of analysis prescribed by other codes were observed to all be greater than those obtained from FEA, showing that the approach taken by other codes is conservative for the studied bridge. The $F_m$ and $F_v$ of external girders obtained by FEA were as much as 30 and 40% less than those of other codes. Inclusion of barrier wall and sidewalk in the analysis showed an additional 18% reduction for $F_m$, with insignificant effect on $F_v$. The live load capacity factor as the safety indicator in the bridge evaluation was calculated analytically by the load and resistance factor method and the mean load method and then correlated with experimental findings of proof load test on the repaired girder.

This study presents a method to develop piecewise linear (PL) performance models for pavement condition data in a pavement management system (PMS). These condition data are usually ordinal and have more than two severity levels. Ordinal logistic regression is conducted to derive probabilities of each individual severity level. The intersections of probability curves are identified as the breakpoints, which can be used to develop PL models. This proposed method was then applied successfully to develop four PL models, for interstates, U.S. routes, North Carolina routes, and secondary routes, using transverse cracking condition data of flexible pavements in a state DOT’s PMS. Results showed that the PL models reflected actual deterioration trends well and that the proposed method is robust.

Intentional and accidental impulsive loads from high-explosive detonations and munitions can result in significant damage to both civil and military facilities. One demand scenario of particular concern occurs during close-in detonation of high explosives. Even for resilient construction methods, such as reinforced concrete walls, these demands can produce undesirable effects including localized spall and breach. A popular form of exterior cladding in the United States consists of precast concrete insulated wall panels. These systems include an exterior concrete wythe, foam insulation layer, and an interior concrete wythe. While insulated wall panels are used to provide an energy-efficient building envelope, the insulation layer can provide a means of mitigating spall and breach of the panel. Thus, the performance of insulated wall panels subject to close-in blast demands is investigated. Both numerical simulations and experimental tests are carried out in order to assess the structural response of this wall system to close-in explosions. The results indicate that the use of insulated concrete wall panels provides enhanced resistance to spall and breach. This improvement is due to the sacrificial performance of the exterior wythe of the concrete panel and the increased standoff distance between the protected face and the threat provided by the insulation layer.

Hurricane Katrina in 2005 displaced or washed away a number of coastal bridges, including the Biloxi Bay Bridge. Although some experimental and numerical studies have been conducted to reveal the failure mechanisms of bridges under extreme nature disasters, very few previous studies are focused on the bridge decks with inclinations. In the present study, the wave forces on the bridge decks with inclinations ($-10°–10°$) under solitary waves have been investigated using the Biloxi Bay Bridge as the prototype bridge. Seven different structure elevations are considered to represent different conditions in field. Wave forces under the prescribed conditions, including the horizontal forces, vertical forces, and moments are analyzed in detail. The results show that the characteristics of wave forces under solitary wave conditions vary with different deck inclinations and structure elevations.

This paper investigates the influence of structural sealant joints on the blast performance of laminated glass (LG) panels, using a comprehensive numerical procedure. A parametric study was carried out by varying the width, thickness, and the Young’s modulus ($E$) of the structural silicone sealant joints, and the behavior of the LG panel was studied under two different blast loads. Results show that these parameters influence the blast response of LG panels, especially under the higher blast load. Sealant joints that are thicker, have smaller widths, and lower $E$ values increase the flexibility at the supports, and hence increase the energy absorption of the LG panel while reducing the support reactions. Results also confirmed that sealant joints designed according to current standards perform well under blast loads. Modeling techniques presented in this paper could be used to complement and supplement the guidance in existing design standards. The new information generated in this paper will contribute toward safer and more economical designs of entire facade systems including window glazing, frames, and supporting structures.

Lavatory-based facilities or lavatory space is an important basic facility of any building. Its functional importance, as well as additional components and facilities to support its function, contrast with other spaces in a building. The uniqueness of lavatory space can be seen after the building is occupied. At this stage, issues relating to its maintenance emerge—in public buildings in particular, including lavatories in higher education institutions. Because of the large number of visitors and staff, lavatories in public buildings and the corresponding high intensity of use, breakdown of, or malfunction of lavatories are common. Hence, use and maintenance of lavatory space is often argued. Cleanliness and functionality is the main goal of lavatory maintenance. In the life cycle of lavatory maintenance, certain stages of building inspection are needed to ensure the physical status of the building. In a wider context, the theory of building assessment also emphasizes the inspection of the building based on appropriate level and performance indicators. This study was conducted to identify existing building assessment standards as to develop a conceptual framework for assessing building performance. Physical inspection was conducted to analyze the current performance of lavatory spaces in faculty buildings. Inspection of the 66 lavatory spaces have been conducted at Faculty 1, Faculty 2, and Faculty 3 in the main campus of Universiti Kebangsaan Malaysia, Bangi, Selangor. The method used is visual inspection based on the CSP1 Matrix building condition measurement tool. Analysis based on the frequency of defects found the connection and damage factors between the components and elements in lavatory spaces.

Recent earthquakes around the world are reminders of the destructiveness of earthquakes and the effect they exact on lives and property. In 1989, the Loma Prieta earthquake resulted in significant damage and fatalities in the San Francisco Bay Area. Multiunit woodframe buildings suffered severe damage as a result of moderate to strong ground motions. Just 5 years later in southern California, the Northridge earthquake caused even more extensive damage to soft-story woodframe buildings. These multifamily residential buildings have upper stories with dense walls but have a large amount of openings for automobile parking at ground level, making them soft (and weak) story buildings. These buildings pose very significant safety risks to tenants, financial risks to owners, and recovery risks to all levels of government. They have been recognized as a disaster preparedness problem, and mitigation efforts are underway in San Francisco with other California cities beginning to follow. In May 2009, FEMA and the Applied Technology Council launched a project to develop a logical methodology for seismic retrofit of (soft-story) weak-story woodframe buildings in seismically active regions of the United States which resulted in the FEMA P-807 report. The objective of the study presented in this paper was to develop a method to optimize retrofit designs for soft-story woodframe buildings based on the FEMA P-807 guideline. Various constraints and objective functions were applied within a genetic algorithm to identify optimal retrofit designs within two building examples.

This paper demonstrates the analysis of the deterioration trends of the various kinds of bridge-construction materials and/or structural designs. The analysis considers bridge-deck areas, rather than discrete counts, to reveal more relevantly the actual constructed capacity that serves traffic mobility and the extent of necessary resources. The study uses the entire database of the U.S. National Bridge Inventory and derives bridge areas by material. The analysis examines material-deterioration aspects of bridge areas at the serviceability limit states. The distinct trends in the accumulation of structural deficiency versus service life of materials provide measures of their deterioration. To determine the operational structural performances based on the deterioration trends, the study uses the criteria of rate and pattern performances. The overall equivalent structural performance considers a multiple-criteria diagnostic approach integrating the rate and pattern with the condition, durability, and longevity performances. The results provide the most comprehensive national network–level comparative experience of the operational structural performances of bridge materials by areas under the actual circumstances. Analysis of the deterioration trends provides an indication of the typical structural deficiency versus service life expected of bridge materials and helps identify critical accumulation of material deterioration by age for focused improvement efforts. The deterioration trends decrease the equivalent structural performances of most bridge materials by approximately 10%. Overall, the equivalent structural performances of bridge materials by areas are slightly lower than by counts. The maximum average accumulation of structural deficiency of all bridge areas is approximately 20% lower than by counts. The average increase of structural deficiency is 0.42% per year, adding to the already existing 9.38% and constituting an average annual increase of structurally deficient bridge areas by 4.48%. The results provide a more objective indication and comparison of structural performance, help forecast future performance, and improve sustainability of bridge materials.

This paper describes a systematic approach of inspection, diagnosis, and repair for masonry walls and their claddings, aiming at facilitating the inspection process and deciding on the repair of these elements. It also helps to combat their degradation. Based on a visual analysis, the inspector is able to identify anomalies and use the proposed system tools to establish correlations with its source, delineate an accurate diagnosis, and determine the best repair technique. The tools that allow a faster and simpler inspection and decision are presented here. The nature of the anomalies, their related causes and appropriate repair techniques are classified, listed, and then related through correlation matrices to create a database. This equips the inspectors with the information they need about the pathology in masonry walls, as well as its classification through suitable terminology, so that a statistical analysis can be performed to find the chief causes of the anomalies. The system was developed under a strategy of proactive maintenance, and it represents an innovation that is as useful to rehabilitation in southern Europe as it is in other regions where masonry walls are a widely used technique.

Experimental investigation on the effect of geometric parameters on the performance of exterior shear wall–floor slab joints subjected to cyclic loading is presented. A prototype building situated at Chennai, India was analyzed and estimated the force components in the exterior shear wall–slab joint. The force components and the dimensions were scaled down for 1/4th model following Cauchy’s law of similitude. Experimental investigations were carried out on eight numbers of 1/4th scaled models. The loading was applied at the end of the slab. The parameters considered are (1) ratio of height of shear wall and the effective width of the slab ($H/W_e$), (2) ratio of thickness of slab to shear wall ($t_s/t_w$), and (3) development length of reinforcing bars. The experimental observations were analyzed to arrive at optimum values of the height of shear wall ($H$), effective width of slab ($W_e$), thickness of shear wall ($t_w$), thickness of slab ($t_s$), and development length ($L_d$). Numerical investigations were employed to compare the experimental results using the finite element software ANSYS. Good correlation was found between finite element analysis and experimental results.

This paper presents use of radiographic imaging (X-ray) in evaluation of existing reinforcing steel and tendon configuration of a structure following a collapse and development of steel retrofit and carbon-fiber-reinforced polymer (CFRP) repairs. A collapsed section in the driving surface in a precast concrete parking deck prompted an engineering evaluation and survey of the entire deck for assessment and repairs to distressed members. Distress was identified in decking members and perimeter spandrel beams in varying forms and degrees. Repairs to the decking members involved supporting the distressed decking using supplemental steel retrofit brackets installed through the double-Tee stems containing prestressing tendons. The precise location of the tendons in the stems needed to be identified to implement this repair in order not to damage the tendons during drilling for through-stem anchors. Radiographic X-ray imaging in this application enabled locating and avoiding the tendons in the stems to support and strengthen the decking member. The supplemental steel brackets also enabled continued and improved operation of an existing expansion joint in the area of repair. Radiographic evaluation technique was also used in identification of steel reinforcement configuration in the perimeter spandrel beams exhibiting cracking at bearing locations with maximum shear. Radiographic exposures were used for evaluation of existing steel configuration and development of CFRP repairs. CFRP repairs were implemented in perimeter spandrel beams while decking surfaces were retrofitted with steel brackets to support the driving surfaces and enable continued expansion and contraction in the existing expansion joints.

Because greenfields available for new developments in congested urban areas are scarce in China, more and more excavations for building basements or other underground facilities (e.g., new metro lines, underground shopping malls, parking garages) have to be carried out in the close proximity of existing metro lines. To ensure project safety, it is essential to know potential adverse effects of excavations on adjacent metro lines in service. Until now, many studies have contributed to the cases of excavations overlying existing tunnels. In contrast, only a few were known for excavations parallel to adjacent existing tunnels. With regard to the responses of existing metro stations to adjacent excavations, few case studies were reported in the literature. Through an extensive field instrumentation program in combination of numerical simulations, this study examines the performance of an oversized deep excavation in stiff clayey deposits and the corresponding responses of the adjacent metro station and twin shield tunnels in service. Taking advantage of the adopted zoned-construction procedure, both wall deflections and ground settlements of this oversized pit were not as significant as those reported in the literature, even smaller than those of long and narrow metro station pits. Consequently, both deformations and displacements of the existing metro line were within acceptable limits, and no obvious structural damage was observed. Throughout the excavation, the two-level island-type metro station exhibited a good structural integrity, which settled uniformly along the transverse direction and tilted slightly along the longitudinal direction. As to the twin shield tunnel linings, the one located within the primary ground influence zone developed considerably larger settlements and deformations than the other one within the secondary influence zone. As a product of the lateral stress relief attributable to soil removal, the tunnel lining experienced apparent elongations in the horizontal direction.

Corrugated steel plate (CSP) culverts are exposed to the risk of soil corrosion because of the location in the soil environment. This paper characterizes the most important factors contributing to corrosion in the soil: resistivity, pH, and moisture content. Tests of soil resistivity based on the geophysical electrical resistivity measurements (Wenner array) are presented. This method allows for soil resistivity measurements at various depths. The conducted experimental tests concerned the six galvanized CSP culverts situated on different types of roads (national, provincial, and local). All tests were conducted in two seasons: summer and spring. The minimum resistivity of the soil in the vicinity of the CSP culverts amounted to $30\mathrm{\Omega }·\mathrm{m}$ and was established near roadway. The pH of the backfill in the tested culverts showed alkaline reaction (8.1–9.3). The largest natural soil moisture of approximately 10% was obtained during the spring. The obtained results indicate the peril of the soil corrosion occurrence in the CSP culverts, especially located on the national and provincial roads. The Pearson’s correlation coefficient was applied to the statistical analysis. A strong correlation between the backfill resistivity and the pH value in summer and spring, and between the resistivity and moisture content in spring, was recorded. Analysis of durability based on the three standards [American Association of State Highway and Transportation Officials (AASHTO), Australian/New Zealand Standard (AS/NZS), and Canadian Highway Bridge Design Code (CHBDC)] shows that the tested culverts meet the requirement for a minimum service life of 40 years (as for culverts), but do not fulfill the required lifetime as for bridges, which is 100 years.

The aim of this study is to investigate the effect of hysteretic models on displacement demands of reinforced concrete (RC) structures having various irregularities and determine more proper hysteretic models for different types of RC structures. The RC structures having irregularities such as soft story and overhang were analyzed with nonlinear pushover and nonlinear time-history methods. Concrete compressive strength, stirrup amount, and the number of stories for the structures were variable parameters. Totally, 25,664 analyses were carried out. Displacement capacities and performance levels of structures were determined using nonlinear pushover analysis. Exceedance ratios of performance levels and displacements demanded from the structures of 100 severe ground motions that occurred worldwide were obtained using nonlinear time-history analysis (NTHA). In NTHA, various hysteretic models were used to define inelastic behavior of RC structures. The analyses show that the hysteretic models have a significant effect on displacement demands of RC structures. Finally, proper hysteretic models are suggested according to the type of structure and purpose of occupancy.

The stiffness and strength of roof units and their connections to supporting beams are fundamental parameters to define the diaphragm behavior of precast structures. In this paper, an analytical method for the calculation of actions in floor-to-beam connections of roof systems without topping slab and without floor-to-floor connections is presented. The proposed procedure can be applied to rectangular single-story precast concrete frames of industrial buildings. One-span, multi-bays regular frames, characterized by symmetry of stiffness and mass distributions are analyzed by assuming floor-to-beam connections with infinite stiffness and strength. The procedure is applied in the perspective of capacity design approach by providing practical formulations for the design and retrofitting of floor-to-beam connections. This approach aims at concentrating the critical regions, where energy dissipation of the structure occurs, at the base of columns designed to fail in bending. An over-resisting behavior of the connections is achieved by over-proportioning them with respect to the resistance of the critical regions. To check the effectiveness of the presented approach, the results obtained with the analytical method are compared with the results of finite element analyses.

The field performance of a new bridge deck system composed of pultruded trapezoidal fiber-reinforced polymer (FRP) tubes wrapped in an outer wrap is described in this paper. The proof of concept FRP deck was installed on a rehabilitated bridge in Bolivar, New York, in 2012 as part of the Highways for LIFE Program from the Federal Highway Administration (FHWA). Based on the field test, the writers developed a three-dimensional finite-element model of the bridge superstructure to further study the interaction of the FRP deck and girders. Experimental and analytical data was used to determine that no composite action was developed by the new deck-girder connection. Comparisons between distribution factors based on field measurements and standard specifications show that the lever rule should be used to estimate live load distribution in similar bridge girder spacing. The serviceability performance of the bridge was found adequate; girder deflections met standard limits, and while the FRP deck experienced deflections larger than typically allowed, they were confined to the localized area of the wheel load and would not affect bridge users.

An experimental study is proposed to compare the corrosion-induced flexural behavior deterioration of beams with various bar types and bar diameters. The proposed study aims to distinguish the effects of the corrosion of different rebars on the flexural behavior of reinforced concrete (RC) beams. Twenty-two RC beams were designed and four variables were considered: the type and the diameter of reinforcement, corrosion loss, and concrete cover. Corrosion was induced in the laboratory using an accelerated corrosion technique. The corrosion-induced strength loss for two types of steel bars is discussed. Extensive statistical analysis is performed to compare the flexural performance of beams with different rebars. The experimental results show that (1) corrosion has a more significant effect on the flexural behavior deterioration in beams with smooth rebars than in beams with deformed rebars; (2) the corrosion-induced performance deterioration has a monotonic decreasing relationship with reinforcement size; and (3) large-diameter steel bars are more appropriate for structural safety.

On the night of June 15, 2007, a corner of one of the most important historical buildings in Salerno (the so called Palazzo Edilizia) collapsed, 80 years after its construction. Such a ruinous failure did not cause any casualties only because the collapsed side was that of the living rooms. The aim of the analysis performed by the authors was mainly the search of the causes of such a ruinous collapse. The article not only deals with the description of the methodology adopted for the analysis but also discusses the results in order to trace general criteria that could be useful for the reliability assessment of the existing masonry buildings.

In developed countries, the building sector is responsible for a very significant share of the total energy consumption. School buildings, because they are places where children are educated and learn to become active members of the society, should be a good example of an efficient use of energy and water. In this study, data of the energy and water consumption of 23 Portuguese schools and their main building characteristics and properties were gathered. This information was normalized to homogenize the data set and then analyzed using advanced clustering techniques. The results show a significant variability in the consumption of different schools, even with similar characteristics, suggesting that the user behavior plays an important role in their efficiency. The complete linkage and Ward’s clustering methods were applied, both produced three clusters, and reference values for electricity and water consumption were defined.

Structural engineers often encounter various unique design and construction challenges during renovations of vintage buildings. If such challenges are not properly addressed, they may result in major consequences. This paper provides a case study of a flawed structural renovation project and discusses the common challenges that engineers may face during renovation projects. The subject building is a six-story vintage residential building with a structure consisting of exterior load-bearing brick masonry walls, interior cast iron and wood columns, and wood floor framing. The renovation project mainly included the addition of a penthouse, addition of a freestanding fireplace and chimney, and converting a roof into a roof garden for the owner of the top story of the building. Due to several serious structural issues that were discovered during and after the renovation project, the penthouse, fireplace, and chimney had to be demolished, and usage of parts of the apartment was restricted to prevent structural members from being overstressed. This paper presents these issues, the authors’ investigation, the remedial work, which was designed by another firm to address the issues, and discusses the standard of care when renovating a vintage building.

Strength degradation of mass concrete of the Dez concrete arch dam was evaluated using inverse analysis methods. A three-dimensional nonlinear finite element model (FEM) was developed here for such an evaluation by considering the effect of interaction between vertical adjacent blocks of the dam. The special attention was paid to the thermal loads. The Young’s modulus and Poisson’s ratio and thermal expansion coefficient of mass concrete of the dam were selected as variable indices for monitoring the strength degradation of dam concrete in the proposed model. An iterative solution scheme was performed to determine the mentioned indices in such a way that a predefined error function would be minimized. An error function has been considered as the sum of the squares of the errors in the nodes of the mesh. An error in a node was defined as the difference between computed displacement vector based on the developed model and the recorded displacement vector with the instruments located in the dam body. The sequences of the solution method have been presented in the paper. The unique characteristic of the suggested method is the contribution of thermal loads in the inverse analysis. The obtained results indicated that the mass concrete of the dam has experienced approximately 34% reduction in its initial elastic modulus, 15% enlargement in its initial Poisson’s ratio, and 25% reduction in its initial thermal expansion coefficient during its 42-year life period (1965–2007). According to the fundamentals of theory of elasticity, it is concluded that the failure surface (the eigenvalues of elastic tensor establish a failure surface for concrete in stress space) of the concrete material of the Dez dam has been contracted significantly. This reduction is strongly thought to be attributable to aggressive hygro-thermo-mechanical effects on downstream parts and may be the result of hygo-thermo-chemo (namely calcium leaching)-mechanical effects at upstream parts of the dam based on similar evidence recorded in the scientific research.

The Kettle River Bridge is an arched, steel cantilevered deck, Pratt Truss bridge. To quantify the live-load performance of the bridge superstructure and provide a baseline for future comparisons, it was instrumented with 151 strain gauges on various beam, stringer, and truss members. In addition, 8 displacement gauges were attached along the truss. All gauges were simultaneously monitored while the bridge was subjected to a nondestructive, live-load test. The recorded bridge response was analyzed to quantify in situ behavior. The measured behavior was then used to validate a finite-element model using solid and frame elements, which was subsequently used to obtain an inventory- and operating-load rating of 2.03 and 2.64, respectively. Based on the results of the test, it was concluded that the large gusset plates added partial fixity to the truss members, as evident from the significant measured in-plane bending strains. However, the beam-and-stringer deck support system showed minimal rotational restraint between consecutive panels and behaved nearly simply supported. The validated finite-element model was used to determine distribution factors. The actual bridge distribution factors were found to be conservative in comparison to those calculated according the AASHTO LRFD specifications, by 17–44%.

As the most important feature of jacked open-ended concrete pipe piles, shear zone has fluence of crucial importance during installing and after penetration. This study conducted a field test in silt deposit to observe the physical phenomenon of shear zone after installation and investigated soil parameter differences from undisturbed soil through laboratory tests. Direct observation on shear zone reveals that the boundary between shear zone and in situ soil is evident. The average soil thickness in the shear zone falls between 6 and 30 mm, which are closely related to natural water content and void ratio in different layers. Laboratory tests on the shear zone show evident compaction during installation, and the soil parameters in the shear zone are sensitive to the jacking installation procedure. Some soil parameters decrease, whereas others increase because of excess pore water dissipating after installation. The extent of the shear zone is helpful in understanding interface friction on pretensioned high-strength concrete (PHC) piles in clay.

Cylindrical steel liquid storage tanks are important components of many process industries. They are usually used to store toxic, flammable, and hazardous liquids. Hence damage to liquid storage tanks may cause serious direct and indirect impacts. Many of the existing tanks in old industrial plants are precode tanks or were designed based on early editions of seismic codes. Meanwhile, the performance of old liquid storage tanks during the past earthquake revealed that they are noticeably vulnerable. In this paper, analytical and empirical probabilistic seismic safety analysis (PSSA) of precode tanks were performed. Fragility curves were developed in terms of the height-to-diameter ratio ($H/D$) and the relative amount of stored liquid (% full). To this end, 750 tank-liquid-earthquake analysis cases have been performed. Furthermore, performances of 43 unanchored old liquid storage tanks during three major earthquakes were observed. Results of this study revealed that the $H/D$ can be considered the most important source of uncertainty in PSSA of precode tanks. Moreover, the variation of % full causes shows noticeable changes in the values of fragilities of tanks.

The North Carolina Department of Transportation (NCDOT) identified several mass concrete footings in coastal bridges with cracking that needed to be assessed in the context of current North Carolina mass concrete specifications. Cracked concrete in coastal environments is of particular concern due to the higher potential for corrosion damage. Site visits were made to assess the extent of the cracking observed in mass concrete footings of three different bridges. A finite-element model was developed and used to analyze the footings and assess them for their early age thermal cracking potential. Finite-element model results showed that reasonably sized mass concrete footings that followed typical NCDOT control plans did not have a high likelihood of significant cracking from thermal stresses. However, a much larger mass concrete footing had a distinctly higher risk of significant cracking even when typical NCDOT control plans are followed. Further, cracking was even more likely when formwork was removed early. The model results correlated well with observations from the field. A comparison with temperature rise results from the Schmidt method, as implemented in the design of the mass concrete structural elements, shows the Schmidt method’s limitations in predicting temperature differences for very large mass concrete footings.

Structures are often subjected to vehicle collision, which can be accidental or intentional as in the case of a terrorist attack. This study investigated the performance of three-story steel moment frames with span length of 5 and 10 m subjected to vehicle collision at a first-story column using finite-element analysis software. The progressive collapse potential of the model structures was evaluated first based on the alternate path approach specified in the published guidelines. The vehicle impact analysis showed that all model structures remained stable when the speed of the vehicle was $40\mathrm{km}/\mathrm{h}$. However at the speeds of 80 and $120\mathrm{km}/\mathrm{h}$, progressive collapse occurred at both model structures after collision. The overall damages obtained from collision analysis were significantly larger than those computed based on the sudden column removal approach.

With the rapid growth of the helical piling industry, reliable installation torque estimates and measurements become crucial. This paper presents a theoretical model developed to estimate the torsional resistance of cohesionless soils to helical pile installation. The theoretical torque model was verified using installation records collected from different sites. The paper also highlights factors that affect helical pile installation including soil properties, fluctuation in groundwater levels, shape of pile shaft, pile geometry, and method of helical pile installation. Torque factors, $K_t$, commonly used in the industry to correlate between installation torque and pile capacities, were also assessed and presented in the paper. The results of the study indicated that the torque factor is a function of the load path (i.e., tension or compression). Therefore torque factors in compression and tension, $K_c$ and $K_t$, were formulated and presented in the paper.

Structural failures attributable to corrosion of reinforcement cause enormous damages to marine structures in the severe condition of the Persian Gulf. In this study, a comprehensive set of destructive and nondestructive tests was employed to examine the durability performance of different elements of a 20-year-old jetty located in the marine environment of the south of Iran. The purpose of the research project was the evaluation of the level of damage in the jetty structure which was constructed using prefabricated post-tensioned high-performance concrete (HPC) box beams. The results revealed negligible corrosion level in most elements of the jetty especially those with a sufficient concrete cover on the reinforcement. However, despite the use of HPC in the construction of the jetty structure, insufficient cover thickness for some reinforced concrete elements have intensified the rate of corrosion, and caused some early age corrosion problems. Therefore, based on the test results, a rehabilitation strategy was proposed to repair the jetty. A stochastic model based on Fick’s law was utilized to predict time for the initiation of the corrosion in the current condition and the repaired structure.

Existing structures may be in need of seismic upgrading owing to structural deterioration, change in function or use, increased performance requirements, or modified seismic codes. In recent years, fluid viscous (FV) dampers have received increasing attention because of their notable seismic-reduction capacity and easy installation. This paper outlines the design procedure of seismic upgrading of existing buildings using FV dampers. Discussions are made on some key issues for seismic upgrading using FV dampers, including the analytical damper-brace model under large earthquakes and strategies for damper layout. A case study is made, in which a 21-story hotel built in 1991 was seismic upgraded. One special feature of this project is that only the first six stories can be structurally modified, resulting in limitations on the damper layout. According to the proposed design procedure, 56 FV dampers are suggested for this project, which provide a supplemental damping ratio of 5.3%. As a result, the seismic responses of upper stories could be significantly reduced, which avoids damaging the decoration of the building above its sixth story and enables short and economic construction.

The quality of cold in-place recycling (CIR) is strongly dependent on the capability of proper laboratory investigation and design, and quality control during construction. The objective of this study was to evaluate the quality of the first major foamed asphalt CIR recycled layer in India, laid on a national highway in India. A nonnuclear density gauge (NNDG) and a portable seismic properties analyzer (PSPA) were utilized to determine the density and stiffness of the foamed asphalt recycled layer. In addition, cores and material samples from the recycled layer were also tested in the laboratory for density and stiffness using dynamic modulus tests and the seismic method. The results of tests were related to material properties and critical factors influencing the performance-related properties were identified. Comparisons between laboratory and field sample data were made. Foaming temperature and gradation control of crusher dust were identified as parameters requiring tight control to achieve the required quality. The detrimental effects of excess blending of cement were also revealed. The NNDG and the PSPA were found to be capable of identifying poor quality areas both in midsections and at joints, and to be capable of monitoring the quality of recycled layer.

The structural performance evaluation is presented of 90 reinforced concrete (RC) buildings that collapsed during the October 23 (Erciş) and November 9 (Edremit), 2011, earthquakes in Van, Turkey. A total of 35,000 buildings are damaged or collapsed in the city center and surrounding villages after the Erciş and Edremit earthquakes. Almost all the RC buildings are affected in the region. To evaluate the structural performance of the collapsed buildings, the buildings are evaluated according to structural system properties, specification properties, material properties (concrete and reinforcement steel properties), and soil properties. The results showed that a large proportion of nonengineering RC buildings completely collapsed or were damaged heavily. Most of the RC buildings in the affected area are not designed and constructed in accordance with Turkish code. Also, it was found that 26% of the buildings do not have a building license, 66% of the buildings’ ground floors were used as a commercial or retail space, 36% of the buildings lacked any structural design, 57% of the buildings were not constructed in accordance with their structural drawings, 74% of the structural drawings did not have any detail drawings and beam/column confined zones, the concrete used in many buildings did not have adequate compressive strength, aggregate dimensions were larger than the maximum aggregate diameter for concrete, 60% of the buildings were constructed with unribbed reinforcement steel, and the majority of the buildings (85%) did not have any geotechnical report.

Scour is a major cause of bridge failures, and the Federal Highway Administration (FHWA) now mandates that states assess the susceptibility of their bridge inventory to scour. The authors have developed and described an integrated analysis program (IAP) that allows the user to accurately approximate nonlinear soil behavior around pile foundations within a structural analysis model. This paper describes a study performed to examine the influence of soil stress history on the outcome of a scour susceptibility analysis. Twenty-two models including the superstructure, substructure, and soil reactions were examined in which scour depth, soil type, and inclusion of soil stress history effects were varied. It was found that the stress history of soils had a limited effect on the performance of the bridge analyzed. This result was found to be in contrast to prior findings from studies performed on isolated piles, indicating that performing an integrated-type analysis is key to obtaining an accurate assessment of bridge scour susceptibility.

The strength and behavior of large-diameter reinforcing steel bars with straight anchorages were experimentally investigated. The anchorage details are typical of monolithic girder-column connections used in bridges and buildings in the midcentury. Eleven subassemblage column specimens were examined with different anchorage lengths, bar groupings, amount of transverse steel, and externally applied column axial forces. Test results showed an increase in anchorage capacity because of the presence of transverse steel and externally applied axial force. Experimental results were compared with contemporary design specifications which do not currently account for the beneficial effects of column axial compression acting transverse to the splitting plane. A modification factor was developed to account for the presence of active force applied transverse to the splitting plane to determine anchorage capacity that better estimated the available capacity of the anchorages.

Some toe-deck crack cases in China have been reported after about 10 years of service in suspension and beam bridge steel orthotropic decks with trough stiffeners. In this paper, a reference stress method used in design practice and a hot-spot stress method provided by the International Institute of Welding are used to investigate toe-deck fatigue of the newly built Taizhou Yangtze River Bridge. Shell and solid finite element models with different mesh sizes are compared. The hot spot at the weld toe and the point at the trough-deck intersection are discussed. One is a shell-model hot spot with no weld. The other is a solid-model hot spot with the weld. Hot-spot stress calculated with the shell model is larger than that with the solid model. Different extrapolation methods of hot-spot stress are discussed; stress calculated with the linear extrapolation method is almost the same as with the quadratic method. The stress of the joint under a moving unit wheel load is studied. Fatigue strengths against reference and hot-spot stresses are derived. Fatigue damages under the truck load, evaluated based on the reference stress method and the hot-spot stress method, are compared.