Innovative Prestressed Steel Composite Short-to Medium-Span Bridges

1997 ◽  
Vol 1594 (1) ◽  
pp. 21-33
Author(s):  
Dan Burroughs ◽  
James Lockwood ◽  
Kenneth Price
Keyword(s):  
High Performance ◽  
Precast Concrete ◽  
Modular Space ◽  
Iron And Steel ◽  
Construction Methods ◽  
Space Truss ◽  
Integral Abutments ◽  
Jointless Bridges ◽  
Steel Composite ◽  
Bridge Performance

Methods for combining both prestressing, high-performance steel and composite concrete decks to improve bridge performance, construe-tibility, aesthetics, and economy are reviewed. The designs are part of a study sponsored by the American Iron and Steel Institute. Five bridge concepts have been developed to the preliminary design phase, including plan details and cost comparisons. Single- and two-span bridges with span lengths of between 24.4 and 54.9 m (80 and 180 ft) have been studied. The alternates developed use prestressing both longitudinally in the main structural components and transversely in the deck. Alternates include a modular space truss, a twin warren truss, a composite steel box, and steel girders. All alternates have either a cast-in-place or a precast concrete deck. Advantages include improved durability and reduced maintenance with the use of prestressing in the deck, which eliminates deck cracking. The use of corrosion-resistant steel eliminates painting requirements. Elimination of deck joints and use of integral piers and abutments also improve durability. Economy can be improved with the combined efficient use of steel, prestressing, and concrete; with the use of jointless bridges and integral abutments and piers; and by increasing shipping lengths, reducing the number of splices, and optimizing construction methods, which are integrated into the design. Construction issues are reviewed to reduce fabrication costs and to simplify bridge erection.

BETHLEHEM LUKENS PLATE HPS-70W

Alloy Digest ◽  
2000 ◽  
Vol 49 (12) ◽  
Keyword(s):  
Fracture Toughness ◽  
Corrosion Resistance ◽  
Tensile Properties ◽  
High Performance ◽  
Iron And Steel ◽  
Cooperative Agreement ◽  
Federal Highway ◽  
High Performance Steel ◽  
Department Of The Navy ◽  
Steel Institute

Abstract BETHLEHEM LUKENS PLATE HPS-70W is a high-performance steel (HPS) developed through a cooperative agreement among the Federal Highway Administration (FHWA), the American Iron and Steel Institute (AISI), and the Department of the Navy. This steel is an improved version of ASTM A 709 grade 70W. This datasheet provides information on composition and tensile properties as well as fracture toughness. It also includes information on corrosion resistance as well as forming and joining. Filing Code: SA-506. Producer or source: Bethlehem Lukens Plate.

scholarly journals Influence of Rapid Heat Treatment on the Shrinkage and Strength of High-Performance Concrete

Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4102
Author(s):  
Jan Stindt ◽  
Patrick Forman ◽  
Peter Mark
Keyword(s):  
Heat Treatment ◽  
High Performance ◽  
High Performance Concrete ◽  
Treatment Time ◽  
Precast Concrete ◽  
Concrete Strength ◽  
Shrinkage Strain ◽  
Temperature Treatment ◽  
Production Flow ◽  
Steel Fibres

Resource-efficient precast concrete elements can be produced using high-performance concrete (HPC). A heat treatment accelerates hardening and thus enables early stripping. To minimise damages to the concrete structure, treatment time and temperature are regulated. This leads to temperature treatment times of more than 24 h, what seems too long for quick serial production (flow production) of HPC. To overcome this shortcoming and to accelerate production speed, the heat treatment is started here immediately after concreting. This in turn influences the shrinkage behaviour and the concrete strength. Therefore, shrinkage is investigated on prisms made from HPC with and without steel fibres, as well as on short beams with reinforcement ratios of 1.8% and 3.1%. Furthermore, the flexural and compressive strengths of the prisms are measured directly after heating and later on after 28 d. The specimens are heat-treated between 1 and 24 h at 80 °C and a relative humidity of 60%. Specimens without heating serve for reference. The results show that the shrinkage strain is pronouncedly reduced with increasing temperature duration and rebar ratio. Moreover, the compressive and flexural strength decrease with decreasing temperature duration, whereby the loss of strength can be compensated by adding steel fibres.

Investigation of Grouted Coupler Connection Details for Accelerated Bridge Construction

2021 ◽  
pp. 036119812199939
Author(s):  
Brent Phares ◽  
Yoon-Si Lee ◽  
Travis K. Hosteng ◽  
Jim Nelson
Keyword(s):  
Crack Width ◽  
High Performance ◽  
Static Load ◽  
High Performance Concrete ◽  
Precast Concrete ◽  
Chloride Penetration ◽  
Load Testing ◽  
Test And Evaluation ◽  
Load Tests ◽  
Precast Elements

This paper presents a laboratory investigation on the performance of grouted rebar couplers with the connection details similar to those utilized on the precast concrete elements of the Keg Creek Bridge on US 6 in Iowa. The testing program consisted of a series of static load tests, a fatigue test, and evaluation of the chloride penetration resistance of laboratory specimens. The goal of this testing was to evaluate the ability of the grouted rebar couplers to develop flexural capacity at the joint between the precast elements as well as the durability of the connection. For structural load testing, seven full-scale specimens, each with #14 epoxy-coated rebars spliced by epoxy-coated grouted couplers, were fabricated and tested in three different loading cases: four-point bending, axial tension plus bending, and a cyclic test of the system in bending. The static load testing demonstrated that the applied axial load had a minimal effect on the formation of cracks and overall performance of the connection. When ultra-high performance concrete was used as a bedding grout, the initiation of crack was slightly delayed but no considerable improvement was observed in the magnitude of the crack width during loading or the crack closure on unloading. The results of the seventh specimen, tested in fatigue to 1 million cycles, showed little global displacement and crack width throughout the test, neither of which expanded measurably. No evidence of moisture or chloride penetration was detected at the grouted joint during the 6-month monitoring.

scholarly journals Experimental and Numerical Study for the Shaping Formation of SCST Structures by Cable-tensioning

2013 ◽  
Vol 7 (1) ◽  
pp. 77-83
Author(s):  
J.W. Kim ◽  
J. H. Doh ◽  
S. Fragomeni
Keyword(s):  
Numerical Study ◽  
Geometric Model ◽  
Small Scale ◽  
Element Analysis ◽  
Construction Technique ◽  
Construction Methods ◽  
Space Truss ◽  
Test Models ◽  
Scale Test ◽  
Joint Behaviour

This paper discusses the behaviour characteristics of the shaping formation of Single-Chorded Space Truss (SCST) structures by means of cable-tensioning of bottom chords. The innovative technique is fast and economical and issued in many types of space structures. The small-scale test models presented herein consist of uniform pyramids with multi-directional ball type joints which are erected into their final shape by cable-tensioning. Since the joint behaviour is very significant in studying the shaping of SCST structures, basic tests for beam and pyramidal units were performed. The feasibility of the proposed cable-tensioning technique and the reliability of the established geometric model were confirmed by finite element analysis. The proposed cable-tensioning technique indicates that the behaviour characteristic of joints is very important in the shaping formation of SCST structures. More specifically in situations where heavy cranes are inaccessible, the cable-tensioning construction technique has proven to be an easy and reasonable method compared to conventional construction methods that typically include heavy cranes and scaffolding.

The Use of Moment-Resisting Frames and Braced Frames for Lateral Stability of Multy-Storey Precast Concrete Structures

2017 ◽  
Vol 259 ◽  
pp. 173-177
Author(s):  
Arthur L. Rocha ◽  
Marcelo de A. Ferreira ◽  
Wilian dos S. Morais ◽  
Bruna Catoia
Keyword(s):  
High Performance ◽  
Precast Concrete ◽  
Tall Buildings ◽  
Shear Walls ◽  
Order Effects ◽  
Lateral Stability ◽  
Infill Walls ◽  
Precast Buildings ◽  
Moment Resisting ◽  
Lateral Displacements

Precast structures for multi-storey buildings can be designed with economy, safety and high performance. However, depending on the height of the building and the intensity of the lateral loads, the lateral stability system must be carefully chosen in order to maximize the global structural performance. In Brazil, the most common method for lateral stability is achieved by moment resisting precast-frames, wherein the moment-rotation response of the beam-column connections are responsible to provide the frame action, which will govern the distribution of internal forces and the sway distribution along the building height. On the other hand, in Europe, bracing systems comprised by shear walls or infill walls are mostly used, wherein beam-column connections are designed as hinged. The aim of this paper is to present a comparison between these methods for lateral stability, applying nine structural simulations with moment resisting precast-frames, shear walls and infill walls solutions, divided in three groups - 3 building with 5 storeys (21 meters high), 3 buildings with 10 storeys (41 meters high) and 3 building with 20 storeys (81 meters high). All first storeys are 5 meters high, while all the others are 4 meters high. The results from all structural analyses are compared. As conclusion, while moment-resisting beam-column connections are more feasible for applying in low-rise precast buildings, the use of shear walls and infill walls are more efficient for tall buildings due to decrease of lateral displacements, having a reduction of second order effects but also increasing the reactions at the foundations of bracing elements.

High-Performance Steels in the United States

2005 ◽  
pp. 11-44
Author(s):  
M. Myint Lwin ◽  
Alexander D. Wilson ◽  
Vasant C. Mistry
Keyword(s):  
United States ◽  
Driving Force ◽  
High Performance ◽  
The United States ◽  
Atmospheric Conditions ◽  
Iron And Steel ◽  
Federal Highway ◽  
The U.S ◽  
Steel Institute

<p>In 1992, the U.S. Federal Highway Administration (FHWA) initiated an effort with the American Iron and Steel Institute (AISI) and the U. S. Navy (Navy) to develop new high-performance steels (HPS) for bridges. The driving force for this project was the need to develop improved higher strength, improved weldability, higher toughness steels to improve the overall quality and fabricability of steels used in bridges in the United States. It was furthermore established that such steels should be "weathering". By this is meant the ability to perform without painting under normal atmospheric conditions.</p>

Sign in / Sign up

Export Citation Format

Share Document