Construction Loads and Vibrations

Construction Loads and Vibrations
Author: Mohsen A. Issa
Publisher:
Total Pages: 278
Release: 1998
Genre: Bridges
ISBN:

The objective and scope of this research was to investigate the effects of construction loads and vibrations on typical newly poured reinforced concrete bridge decks. A compendium was developed that takes into consideration all the factors influencing the effects of construction loads and vibrations on the performance of reinforced concrete bridge decks, in particular, the structural cracking of the concrete. The parameters considered for the evaluation stages were age of concrete, stage and sequence of pours, curing procedures, heat of hydration, strength gain, thermal changes, type of construction, adjacent traffic, adjacent pile driving, and construction equipment. The identification process consisted of a comprehensive literature review and questionnaire survey. Due to the complexity of the subject, limited and often conflicting information was identified. An experimental program was conducted to determine the modulus of elasticity of concrete as well as the maximum curvatures that fresh concrete can withstand. A computer program was developed to identify the best possible pouring sequence for continuous span bridges. Two bridges for which the plans and other relevant information were made available by the Illinois Department of Transportation were modeled for construction loads and vibrations. The time history and dynamic analysis indicated that the sequence of pour has a significant effect on the deformation of the concrete at early ages. The mode shapes obtained by the finite element analysis were used to optimize sensor locations for the dynamic field testing. Locations at the supports and along the two exterior girders of both bridges were selected for instrumentation based on the dynamic analysis results.

Monthly Checklist of State Publications

Monthly Checklist of State Publications
Author: Library of Congress. Exchange and Gift Division
Publisher:
Total Pages: 512
Release: 1994-10
Genre: State government publications
ISBN:

June and Dec. issues contain listings of periodicals.

Railroad Issues

Railroad Issues
Author: National Research Council (U.S.). Transportation Research Board
Publisher: Transportation Research Board National Research
Total Pages: 104
Release: 1992
Genre: Technology & Engineering
ISBN:

Pentagon 9/11

Pentagon 9/11
Author: Alfred Goldberg
Publisher: Office of the Secretary, Historical Offi
Total Pages: 330
Release: 2007-09-05
Genre: Architecture
ISBN:

The most comprehensive account to date of the 9/11 attack on the Pentagon and aftermath, this volume includes unprecedented details on the impact on the Pentagon building and personnel and the scope of the rescue, recovery, and caregiving effort. It features 32 pages of photographs and more than a dozen diagrams and illustrations not previously available.