Planning for Rehabilitation?MWRA Waterworks System
The Massachusetts Water Resources Authority (MWRA) operates and maintains 255 miles of large diameter distribution mains. Existing problems include increasing steel pipe repairs and extensive...
Cables in Trouble
Having inspected more than half of the world's cable stayed bridges, the authors conclude that many are in danger of sudden collapse unless corrosion problems can be stopped....
Design/Construct Contract Speeds Bridge Job
In the name of time and money savings, Pennsylvania DOT is building a bridge using a modified turnkey contract. In contrast, the standard approach is first to design the bridge, then ask...
Rehabbing the Underground Railroad
The Park Ave. Railroad Tunnel brings three commuter rail lines into New York City's Grand Central Station. The four tracks occupy three tubes from 97th St. to 57th St., where...
Cable Stayed Bridges
Two of these five papers on cable-stayed bridges deal with wind analysis. One develops the theory for motion due to flutter and reaches the conclusion that the vibrations are, in general,...
An Alternate Theory of Density Current Propagation
Density current propagation has been previously analyzed by employing a one-dimensional momentum balance in a frame of reference moving with the density current head. Experimental data...
Terrestrial Trends for Building Technology in North America
This paper discusses new building technologies that will develop in the early 1990's to become significant technologies by the mid 1990's. The perspective is...
Lunar Cements/Concretes for Orbital Structures
The lunar surface is a rich source of inorganic building materials for large space structures. Lunar anorthosites can be processed into calcium aluminate cements in high temperature, high...
Explosives Research for Lunar Applications: A Review
Experimental explosives research for lunar operations is reviewed. Each research project had a different objective and together their findings showed that using explosives on the moon...
Structures for a Lunar Base
Constructed facilities will play the key role in the establishment of a lunar base. Such a base is essential in the development of the space frontier and the expansion of humans into space....
The Expandable Platform as a Structure on the Moon
This discussion will show how the expandable platform, initially designed for earth, is translated for use on the moon, and how it answers a multitude of problems while it is used for...
Active Control of Flexural Vibrations in Beams
The feasibility of using piezoelectric actuators to control the flexural oscillations of large structures in space is investigated. Flexural oscillations are excited by implusive loads...
Inflatable Form Construction in Space
In 1973, NASA launched Skylab 1 using a modified third stage of a Saturn V Rocket. This orbital workshop proved to be a success even though problems occurred. This article discusses the...
Containerless Coating Processes for Large Space Structures
Large space structures (LSS) in low earth orbit (LEO) must be able to withstand the deleterious effects of in situ ultraviolet radiation, atomic oxygen, and thermal-cycling-induced microcracking....
Thermal Effects on Large Space Structures with Fixed Attitude
Radiation thermal effects are studied simultaneously on the orbital motion and axial deformation of a very large axially flexible space structure executing planar pitch motion around the...
Simulator for Telerobotic Assembly, Maintenance and Repair of Large Space Structures
A first approximation level computer simulator for telerobotic assembly of large space structures is described. Approach, methodology and initial results are presented. An example based...
Space Truss Construction Studies
The ACCESS Shuttle Flight Experiment, designed to evaluate EVA for on-orbit assembly of erectable truss structure, is reviewed and principal results are summarized. In addition, two on-going...
Space Artificial Gravity Facilities: An Approach to Their Construction
In the course of adaptation to a space microgravity environment, humans experience cardiovascular deconditioning, loss of muscle mass, and loss of bone minerals. One possible solution...
Adaptable Crew Facilities for Future Space Modules
This paper discusses life-size studies recently carried out on advanced crew accommodation features for future space module utilization. The studies are based on exploratory designs for...
Planar Space Structures
This paper describes a construction system which has a number of practical advantages for the development of space structures. It uses relatively thin materials folded into interpenetrated...
Return to search