Journal of Performance of Constructed Facilities

Damage to residential buildings in the United States caused by hurricanes, earthquakes, and other natural hazards is significant. Economic losses average approximately $5.4 billion annually from hurricanes and approximately $4.4 billion a year from earthquakes. In certain areas, multiple hazards pose a significant threat to buildings, however, it is a challenge to optimize allocation of hazard mitigation resources. To cost-effectively mitigate risk from multiple natural hazards, a better understanding of building performance during extreme natural events will provide a basis for achieving cost-effective mitigation of risk from competing natural hazards. This paper demonstrates a risk-cost-benefit framework for assessing damage risks and cost-effectiveness of mitigation strategies for residential buildings using life-cycle and scenario-case analysis. The framework includes probabilistic modeling of the occurrence and intensity of natural hazards, structural system fragility modeling to represent the conditional probability of damage, and a model of total expected cost during different service intervals. The assessment can support improvements in design and construction practices, insurance underwriting, and planning community response to disasters. Many factors that are hard to quantify yet important in risk assessment are discussed for their roles and impacts on hazard mitigation decision making.

In the summer of 2009, a full-scale midrise wood-frame building was tested under a series of simulated earthquakes on the world’s largest shake table in Miki City, Japan. The objective of this series of tests was to validate a performance-based seismic design approach by qualitatively and quantitatively examining the building’s seismic performance in terms of response kinematics and observed damage. This paper presents the results of detailed damage inspections following each test in a series of five shake table tests, and explains their qualitative synthesis to provide design method validation. The seismic test program had two phases. Phase I was the testing of a seven-story mixed-use building with the first story consisting of a steel special moment frame (SMF) and stories 2–7 made of light-frame wood. In Phase II, the SMF was heavily braced such that it effectively became an extension of the shake table and testing was conducted on only stories 2–7, making the building a six-story light-frame multifamily residential building instead of a mixed-use building. All earthquake motions were scalings of the 1994 Northridge earthquake at the Canoga Park recording station with seismic intensities ranging from peak ground accelerations of 0.22 to 0.88 g. The building performed quite well during all earthquakes with damage only to the gypsum wall board (drywall), no sill plate splitting, no nails withdrawing or pulling through the sheathing, no edge tearing of the sheathing, no visible stud splitting around tie-down rods, and reasonable floor accelerations. On the basis of damage inspection, it was concluded that it is possible to design this type of building and keep the damage to a manageable level during major earthquakes by utilizing the new design approach.

Ensuring a complete load path in light-framed wood structures is critical in providing proper load transfer during wind and seismic events. Roof-to-wall metal-connectors are often used to accomplish this goal. Currently, the design and construction community utilizes published metal connector capacities found in manufacturer documentation or other design aids to properly size connectors for a given demand. However, with the ever-increasing trend of using recycled dimensioned lumber and in situ retrofits of older buildings, the limited supply of research in this area is becoming more apparent. At present, the state-of-the-practice does not provide guidance to account for changes in material properties in structurally sound reclaimed or aged lumber. This study uses dimensioned lumber that was extracted from decommissioned buildings, originally built in the 1960s, to examine the effect of reclaimed dimensioned lumber on the design strength of connections by using metal-connectors. Through the use of testing on over 150 samples, this study identifies issues with the current design practice. The metal-connectors show a 20% reduction in uplift design strength, whereas they exhibit a 21% increase in the in-plane design capacity when used in conjunction with the reclaimed lumber. The difference in design capacity for out-of-plane loading appears to be statistically insignificant. As a secondary portion of this study, the design capacities of roof-to-wall connections utilizing two 16d common toenails and a commercially available metal connector were examined. Independent and combined capacities are evaluated. The presence of toenails in roof-to-wall connections is a common situation, as toenails can be used as a construction aid during framing, or toenails can be artifacts left from the original time of construction in retrofit applications. The design capacities of the toenails were determined to be additive to the design capacities of the metal connector for uni-axial loading in uplift or out-of-plane. As a result of rafter splitting, the presence of toenails detracted from the design capacity of the metal connector when loaded uni-axially in-plane.

This paper presents a conceptual development of plastered straw bale composite sandwich wall systems for load-bearing applications. Straw bales are environmentally friendly and may be an alternative to conventional building materials such as masonry blocks for low-rise buildings. An experimental program is conducted to examine the feasibility of the composite system: material testing with three types of plaster materials and structural testing using seven prototype sandwich walls. Test parameters include the effect of reinforcing materials on the behavior of plaster skins and the type of reinforcement such as dense and coarse grid wire-meshes and nonmetallic glass fiber reinforced polymer (GFRP) reinforcing bars. The composite system significantly improves the load-bearing capacity of a straw bale, particularly noticeable when the coarse mesh and GFRP bars are used. The wire-meshes restrain the lateral displacement of the plaster skins and preclude the volumetric expansion of the sandwich walls subjected to axial compression. The test specimens fail by plaster crushing, local buckling, or skin collapse. The specimen with the coarse mesh is recommendable for multistacking applications of straw bale walls, given that such a combination provides low accumulated compliance and high energy absorption capacity when compared with other specimens.

As of October 1, 2008, the Department of the Navy established the requirement that all new buildings constructed for the United States Navy (USN) and United States Marine Corps (USMC) obtain a Leadership in Energy and Environmental Design (LEED) Silver certification by the United States Green Building Council (USGBC). The goal of this requirement is to comply with Executive Order (EO) 13423, which mandates that all government departments reduce energy consumption by 30% by 2015. This research analyzes whether the 11 LEED-certified USN buildings have achieved the expected energy consumption savings. Energy data from LEED-certified buildings was compared with other USN and USMC non-certified buildings of comparable size, usage, and location. Statistical analysis shows that 9 of 11 LEED buildings did not achieve a 30% savings in electricity consumption, while seven of nine met the water consumption savings requirements set in place by EO 13423. Furthermore, this research concludes that the majority of the USN LEED-certified buildings actually showed more electricity consumption than the national averages as published by the Commercial Building Energy Consumption Survey.

Integral abutment bridges (IABs) are now a routine construction and design of choice for many DOTs as bridges are replaced or for new roadways. However, current design and analysis methodologies have not matured substantially because of a lack of available long-term field data. Often current analysis methods predict bridge behavior that is much different from observed. Because of thermal loading, time-dependent effects, and soil-structure interaction, significant irreversible abutment displacements and rotations occur. The primary objective of this paper is to report the actual in situ measurements obtained at four short to medium-long IABs and one weather station, all located in central Pennsylvania. A total of 240 instruments was installed on four IABs during bridge construction and monitored continuously. Monitoring duration at each bridge ranges from 2.5 years to nearly 7 years, having initiated the program in 2002 and continuing to the present. Because of a unique environmental issue, the bridges were not subjected to traffic until December 2007, allowing isolation of traffic loading to thermal loadings and time-dependent effects. Measured IAB responses that are reported herein include: (1) abutment displacement; (2) backfill pressure; (3) abutment rotation; (4) girder rotation; (5) girder bending moment; (6) girder axial force; (7) pile moment; (8) pile axial force; and (9) strain in the approach slab. All measurements demonstrate that IAB response is cyclical, highly nonlinear, and irreversible over time. This study of field measurements over 7 years provides a basis to evaluate and develop future sound IAB analysis and design methodologies.

This study investigated the traffic-induced stresses in the steel deck of a suspension bridge on the Yangtze River, taking into account the dependence of Young’s modulus of asphalt pavement on temperature. In particular, the stress spectra of local areas in the steel deck were studied. On the basis of the massive traffic data collected by a bridge toll system over one month, traffic composition and the vehicle load were statistically analyzed, and then a random traffic flow model that reflected the statistical characteristics of actual traffic flow, was generated. Through a bridge dynamic analysis of the random traffic flow model, a segment of the steel box girder which experiences the greatest stress was selected. The local stress variation and the stress spectrum under traffic flow were analyzed using a finite-element model (FEM). In the FEM analysis process, the impact of the temperature on mechanical properties of the asphalt pavement was considered. The results show that the middle segment of the main span has the largest moment amplitude. In addition, it was observed that the variation of Young’s modulus of asphalt pavement resulting from temperature change can significantly affect the stress of the steel box girder and the stress spectrum at different local areas in steel deck.

Field inspections on long-span steel suspension bridges in China reveal that the pavements undergo a fast deterioration process attributed to the flexibility of suspension bridges and the heavy traffic loads. Such extensive damage and enormous repair costs call for a cost-effective rehabilitation strategy for these bridges. In this paper, the pavement rehabilitation strategy is investigated for the Runyang Suspension Bridge in China with the aid of the life-cycle cost analysis (LCCA). Three alternatives are compared for their economic efficiency, and both agency costs and user costs are taken into account. To consider the uncertainties that abound in the LCCA, probabilistic analyses are made in which the Latin hypercube method is used to provide samples of random variables. According to the LCCA results, the user costs are a considerable proportion of the total costs so that the selection of rehabilitation strategies is significantly influenced by the user costs. In this regard, the second alternative, the double-layer pavement (guss asphalt plus stone matrix asphalt) is the most cost-effective rehabilitation strategy for the bridge. Additionally, sensitivity analyses show that the traffic growth rates, the discount rate, the work zone duration, and the delay cost rate for passenger cars are the most sensitive variables in the user costs. The methodologies and approaches introduced herein can be easily implemented by practitioners and would be of benefit to pavement rehabilitations for steel suspension bridges.

This paper documents the analyses of the underlying causes for longitudinal cracks (LCs) on newly rehabilitated jointed concrete pavement (JCP) on the basis of the field investigations on two projects of rehabbed JCPs in Guangdong, China, as well as a series of tests. Investigation of Qinglian Highway focused on performance of four strategies used to rehabilitate the old Qinglian Road, while performance of three types of separation layer (SL) applied in the rehabbed JCP was the focus of investigation on Jiaoling Project. Furthermore, several other common factors were investigated in both projects, including materials and construction quality during rehabilitation, overloaded truck traffic volume on rehabbed pavements, etc. The findings of the investigations indicated that subgrade replacement caused more LCs on the newly rehabbed JCP than rubblization and break-and-seat which had been used to rehab old QingLian Road because it seemed to have caused plastic deformation and nonuniform compaction of the replaced subgrade attributable to diversity of replacing materials, variances in moisture content of replacing materials, and some problems related to construction. The plastic deformation and nonuniform compaction, in turn, led to uneven settlement of the replaced subgrade and then voids underneath new surface slabs. Voids combined with overloaded truck traffic were attributed to most of LCs on Qinglian Highway. While in Jiaoling Project, SL of 3 cm soft asphalt concrete (AC) with penetration numbers 200–300 performed better in stopping cracking than SL of geotextile and no SL if the original slabs and subgrade were stable because AC could generate higher strain under loading, more efficiently reducing the modulus of elasticity at the interface between base and surface slab and counteracting stresses SL of AC effectively broke the bond between base and surface slab so as to decrease early age cracks. Meanwhile, in both projects, over 80% of cracks were observed on the southbound lanes in which over 80% of overloaded trucks were running, although both directions of each pavement section had been rehabbed with the same structure and same materials. Thus, heavy truck traffic has been one of the major factors causing distresses of highways in China.

The construction process can greatly affect a concrete pile’s structural performance. Poor decisions concerning a pile’s foundation may result in these important structural elements being unsafe so that strengthening interventions may be needed in the future. In extreme cases, the structure may even collapse. The choice of the most suitable construction process is usually a matter for the company constructing the piles and tends to be based either on previous experience or simply on the equipment available at the time. The parameterization model described herein has been devised to induce good construction practices. It includes several factors related to each construction process, and it could influence the structural behavior and durability of concrete pile foundations. The software application combines the input data from a given construction works with a database whose decision parameters are defined. It has been customized for Portugal and is based on expert knowledge acquired from some of its largest construction firms. It gives the most suitable construction process as the output plus a list of reasons for the decision. It also establishes relationships between the result and a second database that compiles the costs and the duration of the selected process, which are essential data at the predesign stage.

Large parts of the world are subjected to one or more natural hazards, such as earthquakes, tsunamis, landslides, tropical storms (hurricanes, cyclones, and typhoons), coastal inundation, and flooding; although, many regions are also susceptible to artificial hazards. In recent decades, rapid population growth and economic development in hazard-prone areas have greatly increased the potential of multiple hazards to cause damage and destruction of buildings, bridges, power plants, and other infrastructure; thus, grave danger is posed to the community and economic and societal activities are disrupted. Although an individual hazard is significant in many parts of the United States, in certain areas more than one hazard may pose a threat to the constructed environment. In such areas, structural design and construction practices should address multiple hazards in an integrated manner to achieve structural performance that is consistent with owner expectations and general societal objectives. The growing interest and importance of multiple-hazard engineering has been recognized recently. This has spurred the evolution of multiple-hazard risk-assessment frameworks and development of design approaches, which have paved way for future research towards sustainable construction of new and improved structures and retrofitting of the existing structures. This paper provides a review of literature and the current state of practice for assessment, design and mitigation of the impact of multiple hazards on structural infrastructure. It also presents an overview of future research needs related to multiple-hazard performance of constructed facilities.

Corrosion of reinforced concrete piles located in a marine environment is of great concern, as it can reduce the load capacity of the piles and shorten their effective life. The Hampton Roads bridge and tunnel, located where the James River discharges into the Chesapeake Bay, was constructed with precast prestressed concrete piles, which have been exposed to a marine environment for 53 years. In the early 1980s, the Virginia Department of Transportation installed protective jackets on the piles to address the effects of chloride contamination and corrosion damage of the piles. The jackets were constructed by placing reinforcing mesh and a fiberglass stay-in-place form around an existing pile, and grouting the annular space with a mortar fill. The objective of these jackets was to prevent or mitigate corrosion activity by blocking water, oxygen, and chlorides from reaching the pile reinforcement. A study was undertaken to evaluate the effectiveness of the protective jackets through the use of visual evaluation, chloride analysis, and jacket autopsy. The study determined that corrosion was active in the precast piles and that the jackets were not mitigating corrosion activity in the piles. It was concluded that this type of jacket provided neither an effective repair to piles suffering from corrosion nor an effective method of protecting a pile from exposure to chloride-bearing water.

One of the most severe exposure conditions for concrete structures is a sewage environment where various kinds of chemical and biological aggressive ions exist. These substances react with concrete through different mechanisms and lead to the deterioration of concrete and corrosion of the reinforcement. Most of the publications have focused on a biogenic sulfuric acid attack on concrete exposed to sewage, and not many authors have considered other aggressive phenomena, such as chloride diffusion and carbonation in a sewage environment. In this paper, the level of damage in concrete structures of a sewage treatment plant was assessed by a comprehensive set of experiments. The test results showed that a complex attack occurred in poorly constructed structures, which deteriorated concrete and caused cement paste decomposition, efflorescence formation, spalling of concrete, the occurrence of cracks, and considerable chloride penetration in concrete resulting in the corrosion of the reinforcement.