Modular Bridge Expansion Joints for Lacey V. Murrow Floating Bridge

1997 ◽  
Vol 1594 (1) ◽  
pp. 163-171 ◽  
Author(s):  
John A. Van Lund ◽  
Mark R. Kaczinski ◽  
Robert J. Dexter

The Lacey V. Murrow Bridge (LVM Bridge) is a 2013-m-long floating bridge on Interstate 90 across Lake Washington in Seattle, Washington. Single-support-bar, swivel-joist modular bridge expansion joint systems are located at each end of the bridge between the shore approach spans and the floating pontoons. These joints were designed for 960 mm of longitudinal movement as well as horizontal and vertical rotations caused by wind, wave, temperature, and changes in lake level elevation. A similar joint in an adjacent floating bridge had experienced premature fatigue cracking at welded attachment details because of low fatigue strength. For the LVM Bridge the joint components were fatigue tested and designed by using fatigue limit-states loads, resulting in welded attachment details with improved fatigue strength. In addition, a stiffer center beam and reduced center-beam span lengths produced lower fatigue stress ranges. Joint movements and rotations, fatigue design methodology, results of dynamic analyses, field measurements of the dynamic response, and construction details are described. The total cost of the LVM joints was 1 percent of the final bridge cost. The Washington State Department of Transportation required a 5-year guarantee for the LVM joints. These are the largest modular bridge expansion joints in the United States to be tested and designed for fatigue.

Author(s):  
John A. Harrison ◽  
Thomas R. Cooper ◽  
Lina Lawrence ◽  
Bryan Williams ◽  
Charity Duran Ketchum ◽  
...  

Installing light rail transit across a floating roadway bridge presents many unique challenges, foremost of which is how to design the multidimensional moving joints at both ends of transition spans between the fixed and floating structures. A technical solution to this technical challenge has been proposed, analyzed, modeled, designed, and prototype tested in the context of the East Link Extension, a light rail transit project being carried out by Central Puget Sound Regional Transit Authority (Sound Transit). Described are the planning, execution, and results of a full-scale prototype testing program of the proposed Curved Element Supported Rail (CESuRa) Track Bridge System, based on the relationship of curved rail supports in two independent planes that adjust in response to the movements of the Interstate 90 (I-90) Bridge. The prototype CESuRa track bridges performed as expected; the information gathered and lessons learned will greatly benefit the final design, the production track-bridge fabrication, and the installation process. Also discussed is the anticipated performance of these track bridges on the I-90 structure in conjunction with the proposed direct fixation track system, fixed rail anchors, and sliding rail expansion joints to be strategically located across the 1.1-mi I-90 Bridge. Built in 1989, the I-90 Bridge is the fifth-longest floating bridge in the world and carries three westbound and two reversible lanes of traffic between Seattle and Mercer Island, Washington. The bridge will be reconfigured to carry four westbound lanes, and the reversible lanes will be converted to light rail transit.


2010 ◽  
Vol 19 (2) ◽  
pp. 238 ◽  
Author(s):  
William E. Mell ◽  
Samuel L. Manzello ◽  
Alexander Maranghides ◽  
David Butry ◽  
Ronald G. Rehm

Wildfires that spread into wildland–urban interface (WUI) communities present significant challenges on several fronts. In the United States, the WUI accounts for a significant portion of wildland fire suppression and wildland fuel treatment costs. Methods to reduce structure losses are focussed on fuel treatments in either wildland fuels or residential fuels. There is a need for a well-characterised, systematic testing of these approaches across a range of community and structure types and fire conditions. Laboratory experiments, field measurements and fire behaviour models can be used to better determine the exposure conditions faced by communities and structures. The outcome of such an effort would be proven fuel treatment techniques for wildland and residential fuels, risk assessment strategies, economic cost analysis models, and test methods with representative exposure conditions for fire-resistant building designs and materials.


2011 ◽  
Vol 11 (16) ◽  
pp. 8809-8823 ◽  
Author(s):  
N. Hiranuma ◽  
S. D. Brooks ◽  
J. Gramann ◽  
B. W. Auvermann

Abstract. Housing roughly 10 million head of cattle in the United States alone, open air cattle feedlots represent a significant but poorly constrained source of atmospheric particles. Here we present a comprehensive characterization of physical and chemical properties of particles emitted from a large representative cattle feedlot in the Southwest United States. In the summer of 2008, measurements and samplings were conducted at the upwind and downwind edges of the facility. A series of far-field measurements and samplings was also conducted 3.5 km north of the facility. Two instruments, a GRIMM Sequential Mobility Particle Sizer (SMPS) and a GRIMM Portable Aerosol Spectrometer (PAS), were used to measure particle size distributions over the range of 0.01 to 25 μm diameter. Raman microspectroscopy was used to determine the chemical composition of particles on a single particle basis. Volume size distributions of dust were dominated by coarse mode particles. Twenty-four hour averaged concentrations of PM10 (particulate matter with a diameter of 10 μm or less) were as high as 1200 μg m−3 during the campaign. The primary constituents of the particulate matter were carbonaceous materials, such as humic acid, water soluble organics, and less soluble fatty acids, including stearic acid and tristearin. A significant fraction of the organic particles was present in internal mixtures with salts. Basic characteristics such as size distribution and composition of agricultural aerosols were found to be different than the properties of those found in urban and semi-urban aerosols. Failing to account for such differences may lead to errors in estimates of aerosol effects on local air quality, visibility, and public health.


Author(s):  
Hossein Khalili Shayan ◽  
Javad Farhoudi ◽  
Alireza Vatankhah

Abstract Radial gates are common structures in irrigation projects. This paper presents some theoretical-based equations for explicit estimation of the discharge from the radial gate under free and submerged flow conditions using Energy and Momentum (E-M) principles. The proposed equations were calibrated using extensive experimental data collected from the literature and this study for three types of radial gates under free and submerged flow conditions. The submergence threshold of radial gates is concluded, based on the concepts of hydraulic jump and the intersection of free and submerged head-discharge curves. The results indicated that the error in estimating the discharge increases under transition ( − 2.5 ≤ Sr% ≤ + 2.5), gate lip (1 < y0/w ≤ 2), and high submerged (yt/y0 ≥ 0.95) flow conditions. However, in these flow limit conditions, the discharge error can be considerably decreased by adjusting the tailwater depth to flow depth just after the gate and using the energy equation for the sections before and after the gate. The efficiency of the proposed methods was evaluated based on the data series from field measurements of radial gates in 29 check structures at irrigation canals in the United States and Iran. The results showed that the discharge could be estimated using the proposed equations in field conditions with acceptable accuracy.


Author(s):  
Ian G. Buckle

The control of structures to improve their performance during earthquakes was first proposed more than a century ago. But it has only been in the last 25 years that structures have been successfully designed and built using earthquake protective systems. Today these systems range from simple passive devices to fully active systems. This paper focuses on passive control and reviews recent developments in the state-of-the-art. Passive systems include tuned mass dampers, seismic (base) isolation systems, mechanical energy dissipators, and the like. Major developments in the theory, hardware, design, specification, and installation of these systems have permitted significant applications to buildings, bridges, and industrial plant. Applications are now found in almost all of the seismically active countries of the world, but principally in Italy, Japan, New Zealand and the United States. Noteworthy advantages have been demonstrated when retrofitting existing structures, and designing high-performance structures such as hospitals, emergency response facilities, defense installations, and critical bridges. Field experience in recent earthquakes has confirmed these expectations. There are however limitations to the use of passive systems and these deserve further study and research. They include the uncertainty of response in the near field of an active fault, the non- optimal behavior of passive systems for both small and large earthquakes, and a lack of certainty about the ultimate limit states in unexpectedly large events. As a consequence, in some jurisdictions, code provisions for passive systems are more onerous than for conventional construction, which is a strong disincentive to their use. The limited availability of design guidance in text books, code commentaries, and other design aids are further impediments to the wider use of these systems.


2017 ◽  
Vol 2638 (1) ◽  
pp. 113-121
Author(s):  
Stephen T. Benedict ◽  
Thomas P. Knight

The Hydraulic Engineering Circular 18 (HEC-18) pier scour prediction equation is the most widely used pier scour prediction equation in the United States, if not the world, and understanding the equation’s performance is of interest to the bridge engineering community. Previous evaluations of the equation’s performance were limited to smaller sets of laboratory and field data. In 2014, the U.S. Geological Survey, in cooperation with the South Carolina Department of Transportation, published a U.S. Geological Survey pier scour database, consisting of 569 laboratory and 1,858 field measurements of pier scour. This extensive database is a valuable resource for evaluating the HEC-18 pier scour equation, which is the primary focus of the investigation presented in this paper. Although comparing predicted and measured values is a common method for evaluating the performance of a prediction equation, the present investigation used a different approach and evaluated the HEC-18 equation by comparing selected data from the USGS database with the dimensionless relationship used to develop the original equation. This alternative approach highlighted some of the strengths and weaknesses of the equation, which are not as evident in the more common approach of comparing predicted and measured values. The findings of the investigation are presented in this paper.


Author(s):  
Joe P. M ahoney ◽  
Linda M. Pierce

A review of transfer functions for mechanistic-empirical design procedures is addressed. Specific emphasis is placed on those transfer functions currently used by the Washington State Department of Transportation (WSDOT) and shift factors that relate estimates of laboratory to field fatigue cracking. To achieve this goal, brief discussions about how the WSDOT transfer functions were developed or chosen are presented. A comparison of WSDOT with South African transfer functions is presented. This comparison is of special interest because the South African transfer functions have been updated recently and are in part based on extensive accelerated pavement testing. Finally, mechanistic-empirical overlay designs have been performed by WSDOT for more than 10 years, and a selection of prior overlay projects is reviewed to examine fatigue cracking shift factors. Only projects exhibiting fatigue cracking or its early manifestation are used. The annual visual distress surveys contained in the WSDOT Pavement Management System make this review a bit easier because all pavement sections on the WSDOT route system have been systematically monitored for the preceding 26 years. The conclusion is that the laboratory-based tensile strain relationship currently used by WSDOT must be shifted to predict field fatigue cracking. Such shift factors appear to fall most commonly into a range between 4 and 10.


2019 ◽  
Vol 2019 ◽  
pp. 1-11
Author(s):  
Jingsong Shan ◽  
Hongmei Shao ◽  
Qiuzhong Li ◽  
Peili Sun

Two kinds of asphalt pavement with thick asphalt layers were used to construct two samples. In structure I, a semirigid base and graded crushed stone subbase were used. In structure II, a granular base and semirigid subbase layer were used. Responses of the two structures under traffic loads were measured using optical fiber sensors, and the differences between theoretical model results and field measurements were analyzed. Field measurements show that vertical compressive stress in structure I is larger than that in structure II. The maximum tensile strain of the asphalt layer is located at the bottom of the AC-25C layer in structure I and at the bottom of the AC-25F layer in structure II. The latter is significantly larger than the former, indicating the possibility of fatigue cracking induced by traffic load is higher in structure II. The measured tensile horizontal strain at the bottom of the semirigid layer is relatively low (<30εμ) in both structure I and structure II. In theoretical model, static modulus, dynamic modulus, and interface bonding ability are considered and theoretical responses are calculated. There are significant differences between the theoretical results and field test data. In the theoretic model, the material properties of layers and bonding status of adjacent layers all influence the results. In order to reduce the difference between the calculated and measured results, numerous material tests and field tests should be carried out.


ARCTIC ◽  
1965 ◽  
Vol 18 (2) ◽  
pp. 70
Author(s):  
Canada. Surveys and Mapping Branch

In 1935 a National Geographic Society glaciological expedition working in the St. Elias mountain range near the Alaska-Yukon Territory boundary described an unnamed mountain in the area as "magnificent, a granite peak sheathed in snow and ice on the south and west sides, and on the north and east sides has fantastic rock cliffs." Thirty years later this same peak was officially named Mount Kennedy in honour of the late President John F. Kennedy. A surge of activity in the area followed immediately. Senator Robert Kennedy climbed the mountain, an expedition sponsored by the National Geographic Society is engaged in producing a large scale map of the mountain and its environs, and a joint U.S.-Canadian party has just completed a survey through the area which will determine the precise geographic position of the mountain's summit and its elevation. The survey party was composed of six men from the United States Coast and Geodetic Survey and two men from the Surveys and Mapping Branch of the Canadian Department of Mines and Technical Surveys. The main purpose of the work was to connect existing surveys along the Alaska Highway with similar surveys along the Alaskan coast. The work will strengthen the control surveys throughout the area and provide new control points for mapping. The decision to include Mount Kennedy in the survey, while adding a touch of glamour to the operation, greatly increased the difficulties. The survey itself consists of five main stations, connected by traverse, with auxiliary points established at alternate stations to provide additional checks on field measurements. The lengths of the four traverse courses varied from eight to thirty-nine miles; the distances were measured by electronic distance measuring equipment, and the angles were measured with precise theodolites using signal lights and heliotropes for targets. ...


Author(s):  
Naoto Yoshida ◽  
Masahiro Sakano ◽  
Hideyuki Konishi ◽  
Takashi Fujii

Fatigue cracking in steel girder web penetration details is so dangerous that it can break steel girders. A one-meter-long crack was detected in Yamazoe Bridge in 2006. Since a number of highway bridges with such web penetration details may exist in Japan, it is of urgent importance to understand these fatigue-strength properties. However, few fatigue tests have been reported on steel girder web penetration details. The purpose of this study is to clarify fatigue behavior of steel girder web penetration details with a slit through fatigue tests of specimens with these details. We designed and fabricated girder specimens that have steel girder web penetration details, in which cross-beam bottom flanges are connected to each top or bottom surface of a slit by welding. First, we conducted static loading tests to understand the stress distributions around web penetration details. Second, we conducted fatigue tests to examine fatigue crack initiation and propagation behavior and fatigue strength.


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