The Washington State Department of Transportation (WSDOT) frequently employs deep pile or caisson... more The Washington State Department of Transportation (WSDOT) frequently employs deep pile or caisson bridge foundations for its bridge structures. Deep pile and drilled shaft foundations are increasingly important for seismic design in Washington state, because of increased seismic design load demands in bridge design specifications. A
This research was conducted to develop improved methods of predicting camber in prestressed concr... more This research was conducted to develop improved methods of predicting camber in prestressed concrete girders. A computer program was written to calculate camber as a function of time. It takes into account instantaneous and time-dependent behavior of the concrete and steel and performs the calculations in a series of time steps. It was calibrated by comparing its predictions with the camber from 146 girders, measured in the fabricators yard both after release and at a later
This document is disseminated under the sponsorship of the U.S. Department of Transportation in t... more This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in this document. This report does not constitute a standard, specification, or regulation. The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers ’ names appear in this report only because they are considered essential to the objective of the document. Quality Assurance Statement The Federal Highway Administration (FHWA) provides high-quality information to serve Government, industry, and the public in a manner that promotes public understanding. Standards and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement. 1. Report No. 2. Government Accession No.
This document is disseminated under the sponsorship of the U.S. Department of Transportation in t... more This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in this document. This report does not constitute a standard, specification, or regulation. The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers ’ names appear in this report only because they are considered essential to the objective of the document. Quality Assurance Statement The Federal Highway Administration (FHWA) provides high-quality information to serve Government, industry, and the public in a manner that promotes public understanding. Standards and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement. 1. Report No. 2. Government Accession No.
This article presents an approach to accelerated bridge design (ABC) that makes use of precast co... more This article presents an approach to accelerated bridge design (ABC) that makes use of precast concrete components and is intended to be applied to common bridge types, such as freeway overpasses. Due to potential structural problems when the bridge is located in a seismic zone, the connection must be strong enough to resist the forces imposed by earthquake loading, as well as easy to assemble with ample allowance for site adjustment. Known as the bridge bent concept, this approach was developed by a team from the University of Washington (UW), the Washington State Department of Transportation, and engineering consultants. In order to investigate the structural properties, laboratory tests were conducted on column-footing subassemblies at UW, and the system was implemented on-site in the replacement of the I-5 Grand Mound to Maytown Interchange, U.S. Rte. 12 over I-5, Br. No. 12/118 Replacement, near Olympia, Washington.
Prefabricated bridge elements and systems (PBES) offers significant cost and time savings, improv... more Prefabricated bridge elements and systems (PBES) offers significant cost and time savings, improved safety, and convenience for traveling public. Precast/prestressed concrete decked girders are prefabricated bridge systems that are often used for accelerated bridge construction (ABC). Precast/prestressed decked concrete girders are composed of concrete I-beam, bulb-tee, or multi-stemmed girder with an integral deck that is cast and prestressed with the girder. A thin cast-in-place concrete slab with minimal reinforcement placed over the top surface is used for mainline bridges to improve the long term performance of precast decked bridges. This paper describes the optimized cross sections of precast decked system for long span bridges with PBES/ABC consideration. Design, fabrication, transportation, construction of precast decked systems is investigated. This paper addresses factors such as the connections between adjacent units, performance of longitudinal joints, use of UHPC for c...
Ductile behavior of bridge systems is desirable under earthquake loadings. The ductility of preca... more Ductile behavior of bridge systems is desirable under earthquake loadings. The ductility of precast prestressed girder bridges can be achieved by proper detailing of intermediate pier diaphragm through extended strands, column bars, and joint reinforcement. Extended strands at intermediate crossbeams are used to connect the ends of girders with diaphragms and resist loads from creep effects, shrinkage effects, and seismic positive moments. The objective of extending the strands is to ensure that the tensile force carried by the strand can be transferred to the opposite side of the diaphragm. The use of ASTM A706 Grade 80 reinforcing steel with this higher capacity can provide benefits to concrete bridge construction by reducing member cross sections and reinforcement quantities. The use of high-strength steel reinforcement with high-strength concrete should result in more efficient use of both materials. This paper describes Washington State Department of Transportation (WSDOT) proc...
On January 26, 2001, an extremely severe earthquake (magnitude 7.7) struck western India (just so... more On January 26, 2001, an extremely severe earthquake (magnitude 7.7) struck western India (just south of Pakistan) centered around Gujarat. The epicenter of the earthquake was only 14.1 miles (22.7 km) below the surface. Many buildings, bridges, and other structures either collapsed or were severely damaged. Based on an inspection visit to the earthquake site, the authors provide an assessment of the damage to existing bridge structures and bridges under construction. This damage is attributed mainly to the lack of adequate seismic design and detailing.
Most highway facility components in the United States are governed by design, construction, maint... more Most highway facility components in the United States are governed by design, construction, maintenance, inspection, and operations codes and regulations of the American Association of State Highway and Transportation Officials (AASHTO) and the U.S. Federal Highway Administration (FHWA). However, to date, highway tunnels in the U.S. do not have comparable national codes and regulations. Recent events, such as the July 2006 ceiling collapse of the I-90 Central Artery/Tunnel (CA/T) in Boston, Massachusetts, have called attention to the need for such national standards. After investigating the CA/T ceiling collapse, the National Transportation Safety Board (NTSB) recommended that the FHWA seek legislation to establish a mandatory tunnel inspection program that would identify critical inspection elements and specify an appropriate inspection frequency. The FHWA requested clearance from the Office of the Secretary of Transportation to proceed with regulatory action to develop National Tu...
This paper describes how the need for a superior and durable concrete capable of resisting enviro... more This paper describes how the need for a superior and durable concrete capable of resisting environmental distress resulted in the development of high performance concrete (HPC) for bridge decks. This paper focuses on the Washington State Department of Transportation (WSDOT) standard practice of using HPC for bridge decks.
This article describes the Tieton River Bridge, site of the first use of self-consolidating concr... more This article describes the Tieton River Bridge, site of the first use of self-consolidating concrete (SCC) for a precast, prestressed girder superstructure by the Washington State Department of Transportation (WDSOT). The author notes that use of SCC reduced production time, allowed for placement with fewer skilled workers, and created a smooth surface to the girders with no signs of bleeding or discoloration. The project involved replacing two 77-year-old bridges and widening lanes and shoulders along and over the Tieton River at a point near Naches in the state of Washington. The project was funded by an Innovative Bridge Research and Deployment (IBRD) program grant; these grants are designed to promote, demonstrate, evaluate, and document the application of innovative designs, materials and construction methods for bridges and other highway structures. The article includes a chart of the concrete mix proportions. A final section briefly explores the structural design, including t...
The allowable level of temporary concrete compressive stress in precast, prestressed concrete com... more The allowable level of temporary concrete compressive stress in precast, prestressed concrete components has been a source of debate in t e co cr te industry for many years. Traditionally, hese str sses have been considered to originate ly from the effects f prestress combined with he self-w ight of a plumb component, evaluated about the major axis. The maximum compressive stress divided by the coefficient of the compressive stress limit det rmines th r quired concrete strength. Although these emporary stresses can occur at any time f om fabrication through erect on into the structure, the critical case is usually at transfer of prestress and subsequent lifting from the form. At this stage, the prestress force is higher and the concrete strength is lower than at any other point in the life of the component. At this early age, concrete is also more susceptible to damage from high compressive stress. As materials and fabrication capabilities in the precast, prestressed concrete indust...
Jointless bridges have been used for bridges in the United States for years since the beginning o... more Jointless bridges have been used for bridges in the United States for years since the beginning of the National Interstate Highway System in 1950s. Through the intervening years, more and more states have utilized Jointless bridge construction in varying degrees establishing national standards and uniform design policy regarding bridge lengths, skews, details or design procedures. Many states since then have moved toward continuous bridges with jointless integral abutments and piers, as standard design and construction practice. Jointless bridge superstructures are constructed to work integrally with the abutments. Movements due to creep, shrinkage and temperature changes are accommodated by using flexible beatings or foundation and through incorporating relief joints at the ends of the approach slabs. In addition to reduced maintenance costs, other advantages of jointless bridges include improved structural integrity, reliability and redundancy, improved long-term serviceability, i...
The Washington State Department of Transportation (WSDOT) frequently employs deep pile or caisson... more The Washington State Department of Transportation (WSDOT) frequently employs deep pile or caisson bridge foundations for its bridge structures. Deep pile and drilled shaft foundations are increasingly important for seismic design in Washington state, because of increased seismic design load demands in bridge design specifications. A
This research was conducted to develop improved methods of predicting camber in prestressed concr... more This research was conducted to develop improved methods of predicting camber in prestressed concrete girders. A computer program was written to calculate camber as a function of time. It takes into account instantaneous and time-dependent behavior of the concrete and steel and performs the calculations in a series of time steps. It was calibrated by comparing its predictions with the camber from 146 girders, measured in the fabricators yard both after release and at a later
This document is disseminated under the sponsorship of the U.S. Department of Transportation in t... more This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in this document. This report does not constitute a standard, specification, or regulation. The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers ’ names appear in this report only because they are considered essential to the objective of the document. Quality Assurance Statement The Federal Highway Administration (FHWA) provides high-quality information to serve Government, industry, and the public in a manner that promotes public understanding. Standards and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement. 1. Report No. 2. Government Accession No.
This document is disseminated under the sponsorship of the U.S. Department of Transportation in t... more This document is disseminated under the sponsorship of the U.S. Department of Transportation in the interest of information exchange. The U.S. Government assumes no liability for the use of the information contained in this document. This report does not constitute a standard, specification, or regulation. The U.S. Government does not endorse products or manufacturers. Trademarks or manufacturers ’ names appear in this report only because they are considered essential to the objective of the document. Quality Assurance Statement The Federal Highway Administration (FHWA) provides high-quality information to serve Government, industry, and the public in a manner that promotes public understanding. Standards and policies are used to ensure and maximize the quality, objectivity, utility, and integrity of its information. FHWA periodically reviews quality issues and adjusts its programs and processes to ensure continuous quality improvement. 1. Report No. 2. Government Accession No.
This article presents an approach to accelerated bridge design (ABC) that makes use of precast co... more This article presents an approach to accelerated bridge design (ABC) that makes use of precast concrete components and is intended to be applied to common bridge types, such as freeway overpasses. Due to potential structural problems when the bridge is located in a seismic zone, the connection must be strong enough to resist the forces imposed by earthquake loading, as well as easy to assemble with ample allowance for site adjustment. Known as the bridge bent concept, this approach was developed by a team from the University of Washington (UW), the Washington State Department of Transportation, and engineering consultants. In order to investigate the structural properties, laboratory tests were conducted on column-footing subassemblies at UW, and the system was implemented on-site in the replacement of the I-5 Grand Mound to Maytown Interchange, U.S. Rte. 12 over I-5, Br. No. 12/118 Replacement, near Olympia, Washington.
Prefabricated bridge elements and systems (PBES) offers significant cost and time savings, improv... more Prefabricated bridge elements and systems (PBES) offers significant cost and time savings, improved safety, and convenience for traveling public. Precast/prestressed concrete decked girders are prefabricated bridge systems that are often used for accelerated bridge construction (ABC). Precast/prestressed decked concrete girders are composed of concrete I-beam, bulb-tee, or multi-stemmed girder with an integral deck that is cast and prestressed with the girder. A thin cast-in-place concrete slab with minimal reinforcement placed over the top surface is used for mainline bridges to improve the long term performance of precast decked bridges. This paper describes the optimized cross sections of precast decked system for long span bridges with PBES/ABC consideration. Design, fabrication, transportation, construction of precast decked systems is investigated. This paper addresses factors such as the connections between adjacent units, performance of longitudinal joints, use of UHPC for c...
Ductile behavior of bridge systems is desirable under earthquake loadings. The ductility of preca... more Ductile behavior of bridge systems is desirable under earthquake loadings. The ductility of precast prestressed girder bridges can be achieved by proper detailing of intermediate pier diaphragm through extended strands, column bars, and joint reinforcement. Extended strands at intermediate crossbeams are used to connect the ends of girders with diaphragms and resist loads from creep effects, shrinkage effects, and seismic positive moments. The objective of extending the strands is to ensure that the tensile force carried by the strand can be transferred to the opposite side of the diaphragm. The use of ASTM A706 Grade 80 reinforcing steel with this higher capacity can provide benefits to concrete bridge construction by reducing member cross sections and reinforcement quantities. The use of high-strength steel reinforcement with high-strength concrete should result in more efficient use of both materials. This paper describes Washington State Department of Transportation (WSDOT) proc...
On January 26, 2001, an extremely severe earthquake (magnitude 7.7) struck western India (just so... more On January 26, 2001, an extremely severe earthquake (magnitude 7.7) struck western India (just south of Pakistan) centered around Gujarat. The epicenter of the earthquake was only 14.1 miles (22.7 km) below the surface. Many buildings, bridges, and other structures either collapsed or were severely damaged. Based on an inspection visit to the earthquake site, the authors provide an assessment of the damage to existing bridge structures and bridges under construction. This damage is attributed mainly to the lack of adequate seismic design and detailing.
Most highway facility components in the United States are governed by design, construction, maint... more Most highway facility components in the United States are governed by design, construction, maintenance, inspection, and operations codes and regulations of the American Association of State Highway and Transportation Officials (AASHTO) and the U.S. Federal Highway Administration (FHWA). However, to date, highway tunnels in the U.S. do not have comparable national codes and regulations. Recent events, such as the July 2006 ceiling collapse of the I-90 Central Artery/Tunnel (CA/T) in Boston, Massachusetts, have called attention to the need for such national standards. After investigating the CA/T ceiling collapse, the National Transportation Safety Board (NTSB) recommended that the FHWA seek legislation to establish a mandatory tunnel inspection program that would identify critical inspection elements and specify an appropriate inspection frequency. The FHWA requested clearance from the Office of the Secretary of Transportation to proceed with regulatory action to develop National Tu...
This paper describes how the need for a superior and durable concrete capable of resisting enviro... more This paper describes how the need for a superior and durable concrete capable of resisting environmental distress resulted in the development of high performance concrete (HPC) for bridge decks. This paper focuses on the Washington State Department of Transportation (WSDOT) standard practice of using HPC for bridge decks.
This article describes the Tieton River Bridge, site of the first use of self-consolidating concr... more This article describes the Tieton River Bridge, site of the first use of self-consolidating concrete (SCC) for a precast, prestressed girder superstructure by the Washington State Department of Transportation (WDSOT). The author notes that use of SCC reduced production time, allowed for placement with fewer skilled workers, and created a smooth surface to the girders with no signs of bleeding or discoloration. The project involved replacing two 77-year-old bridges and widening lanes and shoulders along and over the Tieton River at a point near Naches in the state of Washington. The project was funded by an Innovative Bridge Research and Deployment (IBRD) program grant; these grants are designed to promote, demonstrate, evaluate, and document the application of innovative designs, materials and construction methods for bridges and other highway structures. The article includes a chart of the concrete mix proportions. A final section briefly explores the structural design, including t...
The allowable level of temporary concrete compressive stress in precast, prestressed concrete com... more The allowable level of temporary concrete compressive stress in precast, prestressed concrete components has been a source of debate in t e co cr te industry for many years. Traditionally, hese str sses have been considered to originate ly from the effects f prestress combined with he self-w ight of a plumb component, evaluated about the major axis. The maximum compressive stress divided by the coefficient of the compressive stress limit det rmines th r quired concrete strength. Although these emporary stresses can occur at any time f om fabrication through erect on into the structure, the critical case is usually at transfer of prestress and subsequent lifting from the form. At this stage, the prestress force is higher and the concrete strength is lower than at any other point in the life of the component. At this early age, concrete is also more susceptible to damage from high compressive stress. As materials and fabrication capabilities in the precast, prestressed concrete indust...
Jointless bridges have been used for bridges in the United States for years since the beginning o... more Jointless bridges have been used for bridges in the United States for years since the beginning of the National Interstate Highway System in 1950s. Through the intervening years, more and more states have utilized Jointless bridge construction in varying degrees establishing national standards and uniform design policy regarding bridge lengths, skews, details or design procedures. Many states since then have moved toward continuous bridges with jointless integral abutments and piers, as standard design and construction practice. Jointless bridge superstructures are constructed to work integrally with the abutments. Movements due to creep, shrinkage and temperature changes are accommodated by using flexible beatings or foundation and through incorporating relief joints at the ends of the approach slabs. In addition to reduced maintenance costs, other advantages of jointless bridges include improved structural integrity, reliability and redundancy, improved long-term serviceability, i...
Uploads
Papers by Bijan Khaleghi