Performance evaluation of conventionally reinforced concrete (CRC) bridge superstructure elements with diagonal cracks is of interest to the bridge engineering community. Standardized methods to predict service-level stress magnitudes in cracked bridge girders under combined bending and shear forces are not available. An analysis procedure was developed to determine the response...
Environmental factors and physical properties of latex modified concrete (LMC)
are hypothesized to contribute to early age cracking in bridge deck overlays. Cracking
permits the ingress of moisture and aggressive solutions into the substrate and may
contribute to other subsequent distresses. Understanding the material properties and
mechanisms involved is necessary...
Many conventionally reinforced concrete deck girder (RCDG) bridges were built in the US during the 1950s, throughout the expansion of the Interstate System. Designs followed the AASHO standard of the time, which permitted higher shear stress in concrete and reduced detailing requirements than permitted by current specifications. Many of these...
A need exists to develop a non-destructive testing technique that can identify
the formation and propagation of diagonal tension cracks in conventionally
steel reinforced concrete deck girder (RCDG) highway bridges in the State of
Oregon. Such a technique could be included into a structural health
monitoring (SHM) system installed on...
Article 1: Behavior of Epoxy Injected Diagonally Cracked Full-Scale CRC Deck-Girders.
Many cast-in place reinforced concrete deck-girder bridges (RCDG) remain in the national inventory and exhibit diagonal cracking. Epoxy injection has been in use for several decades as a method for sealing diagonal cracks, but the effects on girder behavior...
Large numbers of vintage reinforced concrete deck-girder bridges remain in the national bridge inventory. Many of these exhibit diagonal cracking and other distress. Due to the design practices of the time, it is common to observe cracks at locations where flexural reinforcing steel is terminated along the span. The presence...
Aging and deficient infrastructure has become a major problem throughout the world. This is particularly evident in the case of reinforced concrete (RC) bridges. The cost of replacing these bridges is often prohibitive, thus engineers must find ways to strengthen them. Many older RC bridges predate the modern understanding of...
In the field of civil infrastructure, bridge desks are typically constructed using high performance concrete (HPC). Concrete bridge decks demand qualities such as low permeability, high abrasion resistance, superior durability, and long design life. Over decades of field and laboratory experience, many HPC bridge decks have been found to be...
Many conventionally reinforced concrete deck girder bridges (RCDG) and their intermediate supporting bent caps were designed during the Eisenhower interstate era of the 1950’s with the AASHO design equations at the time, which subsequently place higher demand on the concrete. The referenced components may exhibit diagonal cracking due to the...
Bridges are a vital component of transportation infrastructure in the United States, and the continual maintenance and preservation of bridges is critical to maintaining their structural capacity and maximizing service life. One of the most significant issues faced by concrete bridges is the infiltration of moisture from the roadway surface...
Low temperature cracking is attributed to tensile stresses induced in an
asphalt concrete pavement that develop when the pavement is subjected to a cold
temperature. Cracking results in poor ride quality and a reduction in service life of
the pavement. Low temperature cracking has been predicted by regression
equations, mechanistic...
Corrosion of reinforcement is recognized as the predominant factor that limits the service life of reinforced concrete (RC) structures exposed to aggressive environments. This corrosion deterioration can lead to damage resulting in capacity loss or even failure. For structures exposed to coastal marine environments or deicing or anti-icing applications, this...
Thermal cracking of asphalt concrete pavements is responsible for millions
of dollars in annual maintenance and rehabilitation costs in the United States and
Canada. Thermal cracking is typically associated with low temperatures in
northern climates and at high elevations. However, another form of thermal
cracking, known as thermal fatigue cracking,...
Structurally efficient and cost-effective solutions are needed to extend the service-life of deficient and aging highway infrastructure around the world. One critical need is to increase the flexural strength of older reinforced concrete (RC) structures to carry heavier and more frequent loads. Titanium alloy bars (TiAB) offer a new opportunity...
Thermal distress in asphalt concrete pavements is a widespread problem around
the world. Thermal cracking can be divided into two modes of distress: low
temperature cracking and thermal fatigue cracking. Low temperature cracking results
from extremely cold temperatures; thermal fatigue cracking results from daily
temperature cycles.
Low temperature cracking is...
Large numbers of reinforced concrete (RC) bridges were built in the past that are now considered seismically deficient. The structural members most likely to be considered deficient are the supporting columns. Typical deficient columns contain inadequate transverse reinforcement and poorly detailed lap splice lengths above the foundation. Insufficient lap splice...
High Performance Concrete (HPC) is used in our crucial pieces of infrastructure, such as bridge decks, due to its enhanced durability and engineering properties. However, HPC is highly susceptible to early-age cracking. Cracking within the first months of a bridge deck’s lifespan can severely hinder its long-term performance and durability....
This paper investigates a particular bridge construction technique
which could result in a significant torsional moment. The
structural member under consideration is a prestressed concrete
girder for which no torsional consideration is made.
Torsional shear stresses can be adequately approximated for
an I-shaped girder. Laboratory model tests were performed to...
The behavior of stirrups engaged by diagonal cracks and under service loads is
largely unknown. Full-size laboratory specimens were loaded to induce diagonal
cracks and subjected to high-cycle fatigue loading to represent a service life of 50
years. Tests indicated little change in the average stirrup stress range and mean...
Large numbers of 1950's vintage conventionally reinforced concrete (CRC) bridges remain in-service in the national bridge inventory. Many of these bridges are lightly reinforced for shear. Evaluation of these bridges to prevent unnecessary and costly repairs requires refined analytical techniques. This dissertation presents finite element (FE) modeling and comparisons of...