A Surface Exploration Vehicle Testbed for Real-Time Control Exerimentation
Current mission scenarios for return to the moon as well as Mars include some robotic systems; for the precursor unmanned mission, these systems will be required to operate under autonomous...
Transfer Vehicle Sizing for Missions to Mars
The purpose of this study is to analyze the interactions between mission and vehicle design parameters, and determine how the selection of a particular trajectory and transit time affects...
Spacecab: A Concept for Commercial Human Spaceflight
This paper will describe the Spacecab conceptual design and operational scenario. Spacecab is not necessarily a unique design solution but it does illustrate a design philosophy that differs...
ARIANE-5 Launch Operations Construction and Operation of a New Launch Complex for Lower Cost, Higher Reliability Missions
This paper describes the main criteria driving the evolution of these facilities : launch rate, vulnerability to accidents, reliability and safety, cost optimization and adaptation to...
Cables Over the Mississippi
As the designer of the Great River Bridge over the Mississippi between Gulfport, Ill. and Burlington, Iowa, Sverdrup Corp., St. Louis, had to find a way to connect the new five-lane crossing...
Seismic Analysis of Bridges: Simplified or Refined Approach
This paper discusses the differences of seismic responses of bridges among various analysis methods and approaches....
Dynamic Loading of a Rigid Frame Bridge
The objective of this paper is to investigate the dynamic response of a rigid frame bridge to two trucks (side by side) passing over the rough bridge deck. The rigid frame bridge is designed...
Bridge Rail Impact Forcing Functions
Bridge rails are designed according to AASHTO standards with a static 10-kip (44.5 kN) lateral load. The computer programs BARRIER VII and COSMOS are used to determine the deflections...
Cumulative Impact of Heavy Permit-Trucks on Steel Bridges
In many parts of North America, special permits are issued to heavy vehicles without considering their cumulative effect on steel bridge components. Such overloads may initiate crack propagation...
Corrosion Resistant Epoxy-Coated Reinforcing Steel
Research conducted in the 1970s to evaluate and develop criteria for nonmetallic coatings to protect steel reinforcing bars embedded in concrete bridge decks from the corrosive action...
Talmadge Bridge Replacement
This paper discusses the design of the main spans and approach spans for the replacement of the Talmadge Bridge for the Georgia Department of Transportation. The design of the concrete...
Monitoring Stay Cable Forces During Construction of the Natchez Trace Parkway Arch Bridge
This paper describes how cable-stay forces were indirectly quantified through the use of simple field measurements. A system was developed and delivered to the contractor and used to make...
Overweight Trucks and Safety of Bridges
Most states face increasing pressure to issue more and heavier overweight truck permits. Current permit checking methods of many states adopt the AASHTO rating concept with or without...
Towards Structural Strength and Safety Evaluation Within Bridge Management Systems
Bridge management systems being implemented by transportation departments in the United States are limited in their ability to consider structural strength and safety when preparing recommendations...
Comparison of Bridge Deterioration Rates
This paper presents the results of a study of rates of deterioration of steel and prestressed concrete bridge superstructures. The results indicate that age is the primary determinant...
Historical Considerations for New Jersey Viaduct
An Historical Bridge Alternatives Analysis report prepared for New Jersey Department of Transportation (NJDOT) for Route 1&9 S.B. viaduct in Newark, New Jersey evaluated the options...
Seismic Evaluation of the Tied-arch Bridge Across the Mississippi River on I-40
The bridge reported in this paper is a two-span steel tied-arch bridge supported on massive caisson foundations. Site specific seismic studies were carried out to establish the ground...
Seismic Response Studies on a Two Span Slab-On-Girder Bridge
A new type of self-equilibrating snap-back (quick-release) test setup is employed to investigate the transverse dynamic response of a two-span continuous slab-on-girder highway bridge....
Seismic Performance of Railway Bridges
Historically, the seismic performance of railway bridges in the U.S.A. has been very satisfactory during earthquakes of this century. There are many possible factors contributing to this...
Seismic Research Program for Highway Construction
This paper provides an overview of the highway research program being conducted by the National Center for Earthquake Engineering Research (NCEER). This six-year program, which is sponsored...
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