Journal of Performance of Constructed Facilities

Field investigation of infrastructure damage following the March 2011, Tohoku, Japan, Tsunami uncovered failure of numerous fuel storage containers as a result of the high inundation depths and velocities associated with the event. Observations focused on two areas, Ishinomaki, Japan and Onagawa, Japan, where inundation depths of up to 6 and 17 m, respectively, were measured. The failure modes observed include: crushing of containers as a result of inward hydrostatic forces or debris impact, tie down failures as a result of elevated buoyancy forces, and sliding failures as a result of the hydrodynamic forces imparted during the event. The loss of restraint resulted in movement of the containers outside of their containment walls, fuel spillage, and ground contamination. Sample calculations based on observed container failure, water levels, and estimated flow velocities illustrate the demands and failure patterns observed. A retrofitting mechanism is proposed to minimize loss of fuel storage containers during tsunami events.

In recent years, buildings and structures in Turkey have frequently failed or suddenly sustained damage because of their own weight or other loads. The most dramatic failure was the Zumrut Apartment Building disaster: a 9-story RC building in Konya that collapsed on February 2, 2004, leaving 92 people dead. This study will investigate the cause of the building damage and failure. The significant mistakes made during the design and construction of the building will also be considered. This study was divided into three sections: site investigation, analytical study, and experimental study. The evaluation of the building failure relating to the vertical load-bearing members will be presented using observations from the site investigations, the test results obtained from specimens taken from the failed building, and the findings of an analytical study involving modeling the building using the finite-element method.

The floor slabs and shear walls together act as a rigid jointed frame in resisting gravity loads and lateral forces caused by wind and earthquake. The junction between the wall and slab is a key force-resisting element that is subjected to severe stress concentration. The performance of the connection can influence the pattern and distribution of lateral forces among the vertical elements of the structure. In the current study, two different reinforcement detailing adopted, such as (1) conventional joint with the provision of U hooks connecting shear wall and slab and (2) slab bars bent 90° at the core region along with the provision of shear reinforcement in the slab. Analytical investigations were carried out to study the performance of the shear wall–slab connection with these detailings. The RC model consists of a material model to predict the failure of brittle materials, applied to a three-dimensional solid element in which reinforcing bars may be included. Good energy dissipation capacities were observed with the provision of shear reinforcement for an effective width of the slab compared with a conventional joint. The experimental results were compared with analytical results carried out using the finite-element software ANSYS, and it was found that the experimental results are in good agreement with the analytical result.

This paper presents the experimental investigation of one-third-scale precast concrete beam-column connections subjected to reverse cyclic loading. The precast specimen and monolithic specimen were designed for the same strength. For the first precast connection, the beam is connected to the column with corbel using a cleat angle with a single stiffener, and for the second precast connection, cleat angle with two stiffeners was used. The subassemblage specimens have been subjected to cyclic displacement controlled lateral loading, applied at the end of the beam. The ultimate load-carrying capacity, load ratio, hysteretic behavior, energy dissipation, equivalent viscous damping ratio, ductility factor, and strength degradation of both the precast and monolithic specimens were measured, and their performance was compared. The results showed that ultimate load-carrying capacity of the monolithic specimen was superior to that of both the precast specimens. The precast specimens were found to exhibit satisfactory behavior compared with the monolithic specimen in terms of energy dissipation and ductility.

Aluminum screen enclosures suffer from significant damage in hurricanes. In an attempt to identify ways to minimize the damage to screen enclosures, experimental investigations were conducted to study how screen enclosures perform when they are subjected to repeated loading cycles. The loading cycles mimic gradually increasing hurricane winds, while considering the fluctuating nature of the wind. Three types of specimens were constructed and tested. Their overall geometry was the same but their bracing strategies were different. Three damage indices were used to analyze the data. Qualitative assessment and comparison of damage was also conducted. Overall, K-type bracing was most effective followed by cable bracing. Lack of bracing resulted in sudden failure. Beam-to-host connections were very critical in preventing catastrophic failure. Suggestions on how to improve beam-to-host connections are provided along with other measures to mitigate the damage on screen enclosures. Where feasible, the most important measure to reduce damage would be the installation of a proper bracing system; however, other proposed measures would also strengthen the structure against hurricane winds.

Degradation of structural material because of floodwater is one of the major damaging effects during flooding events. As a result, thousands of homes in coastal states, especially those that are constructed from wood-based materials, have been destroyed after each severe hurricane. This paper evaluates the performance a new type of composite structural insulated panel (CSIP) after exposure to floodwater. The proposed composite panel is made of low-cost orthotropic thermoplastic glass/polypropylene laminate as the facesheet and expanded polystyrene foam as the core. The proposed CSIP panel is intended to overcome problems of traditional structural insulated panels, especially those resulting from strength degradation. An extensive experimental program was conducted to investigate the flexural strength degradation of CSIPs after exposure to floodwater for various periods of time. The residual flexural strength following full submergence of CSIPs in simulated floodwater was evaluated using a four-point loading test. Furthermore, the experimental results were validated using new analytical models and were observed to be in good agreement. Insignificant strength degradation was recorded by CSIPs, and therefore they demonstrated the potential for their use in sustainable building structures against flood hazards.

A large-scale seismic performance assessment study based on 98 precast buildings, constructed in the high seismicity region of western Turkey, was performed. Structural properties of buildings were obtained from the design projects and then verified by site investigations. Statistical evaluations of inventory buildings have shown that stiffness and ductility capacity of existing buildings are insufficient. This situation indicates that structural deficiencies emphasized in recent earthquakes are not site specific, but wider and common. Seismic performance of precast buildings was estimated using two different demand spectrums and two different calculation methods. Demand spectrums were constructed by considering site-specific properties of the target region and properties of weak soil sites. Seismic performance of buildings was estimated using the capacity spectrum method and the equal displacement approach. Results of these methods indicate that damage distributions are significantly amplified by the weak soil properties. Distribution of building damages showed that the ratio of extensively damaged and collapsed buildings ranged from 20 to 80%, depending on the site amplification. A considerable amount of moderately damaged buildings implies that monetary losses may also be critical.

The resistance of prestressed concrete through-girder (PCTG) pedestrian bridges to lateral loads was studied in response to the increasing number of vehicular impacts in the United States. This research was motivated by the lack of reported studies analyzing the behavior of such bridges to lateral impact loads, as well as their potential vulnerability in comparison with bridges that are better able to redistribute and transfer locally applied impact loads through alternate load paths. Pedestrian bridges are of lighter construction than highway bridges and they do not have the high degree of redundancy, making them more vulnerable to collapse in the event of vehicular impact. Results from static lateral load analyses using three-dimensional, geometrically nonlinear, full-scale finite element (FE) models of a typical bridge system and bridge subassemblages were used to evaluate the characteristics of the system. The FE models were calibrated with experimental test data on typical subassemblages and connection details for PCTG bridges. Results of the experimental part of the program have already been published elsewhere. This paper summarizes the observations obtained from nonlinear static FE analyses of a PCTG pedestrian bridge system subjected to lateral impact loads. The analyses indicated that the location of impact, the type of connector, and the flexibility of the end support details affected bridge performance. Improved connection details are suggested for enhanced PCTG pedestrian bridge performance.

This paper summarizes a case study of using three-dimensional (3D) light detection and ranging (LiDAR) scanner technology in bridge postblast geometric assessments. Terrestrial 3D LiDAR scanners can generate dense point clouds of position information that can be used to establish baseline geometric information for structures and to establish critical dimensional footprints for before and after event comparisons. For close range blast effects, the preblast and postblast scans of a bridge are proposed to establish blasting induced effects and damage information. The Colony Road culvert bridge was monitored for a nearby construction blasting, where full-scale 3D scans of the bridge have been conducted before and after blasting. The critical sections and geometries are then compared to ensure the safety of the bridge.

Two underground concrete box culverts were installed below ground on Plantation Drive in the City of Benbrook, Texas, in 1991. The culverts consisted of precast segments with case-in-place (CIP) collars/bends. The concrete started deteriorating and spalling at several CIP bend locations as early as 1993. The concrete continued to deteriorate over the subsequent years. An investigation was launched herein to determine the cause and extent of the concrete degradation. The geotechnical investigation involved resistivity imaging, soil boring, and photo-ionic detection for exploring any soil contamination around the culverts that may enhance the concrete deterioration. Visual inspection of the deteriorated concrete helped to examine the clear concrete cover. Concrete cores were taken and tested for strength and deterioration. No soil contamination was observed at the site. The culvert water acidity was neutral. Therefore, the contamination in the underground tunnel/box culvert may not be related to the soil contamination or leakage from sewerage pipes around the culvert areas. The collected concrete core inspection and testing showed that most of the bend concrete is badly deteriorated. Although the strength of some of the more intact bends is acceptable, most of the bend concrete simply does not have sufficient strength, integrity, and ductility to effectively carry the service loads imparted on them. The rebars inside the cores were extensively deteriorated and lost much of their strengths and ductility. The visual inspection showed that the insufficient clear covers were used in the culvert wall and the slab; this was the likely cause of the premature concrete deterioration. On the basis of the investigation performed herein, immediate rehabilitation steps were recommended.

Whitetopping (WT) or ultrathin whitetopping (UTW) overlay is defined as a portland cement concrete overlay on an existing deteriorated hot mix asphalt (HMA) pavement to improve both the structural and functional capability of HMA. During the past two decades, UTW overlays have gained great acceptance as an alternative to HMA overlay. However, there is a lack of a reliable method to evaluate the performance of in-service UTW pavements. Because of the small slab sizes of UTW pavements, backcalculation of pavement layer properties, based on the falling weight deflectometer, is challenging. This study developed a new approach, the Critical Distance Method, based on Saint-Venant’s principle, to backcalculate the portland cement concrete and equivalent substructure moduli of UTW pavement. It was proven to be an effective approach to determine the layer properties of UTW pavement, based on the finite element simulations. Traditional backcalculation methods, such as AREA theory and the MODCOMP6 software program, were used as comparison in the simulation and in a case study. It was found that the Critical Distance Method is more accurate for evaluating UTW pavement. Further field verification of the Critical Distance Method is needed.

This paper provides a detailed study of remediation work on the core zone of a damaged earth-fill dam. The relevant material includes a review of the dam surface survey data, leakage monitoring data, drilling method, grouting material, and drilling and grouting procedure. A compaction grouting method was selected as the remediation technique. In addition, the reduction and prevention of leakage and settlement were assessed. Compaction grouting was successful for filling voids, closing channels, and compacting the disturbed core soils. The loose or voided zones were properly filled, and the leakage was reduced after compaction grouting. Verification of the compaction grouting work was performed by evaluating the grouting pressures and volumes injected internally and by monitoring the dam leakage rate and tracer externally. All of these factors provide a good indication of changes inside the core of the dam, including reduction or closure of the leakage channels in the dam core.