Dams Going Safely over the Top
Many older dams can't pass updated design floods without overtopping the embankment crest. Conventional upgrade methods, enlarging spillways or raising crests, are expensive....
Application of a Dolos Structural Design Procedure
Dolos concrete armor units are widely used to protect coastal structures. New developments in armor unit strength design permit the armor unit designer to optimize the dolos parameters...
Cost Effective Risk Allocation for Coastal Engineering Projects
Project participants will benefit significantly by routinely taking a more systematic, structured, and global view of risk than is sometimes done at present. Enhanced and broadened cognizance...
Passive Acoustic Emission for Quantitative Evaluation of Freeze Thaw and Alkali Aggregate Reaction in Concretes
Several experiments are reported in which the progression of freeze thaw (FT), alkali-aggregate reaction (AAR), and internal cracking caused by mechanical loading were monitored using...
Damage Assessment in Concrete Using Acoustic Emission
An acoustic emission (AE) is a localized rapid release of strain energy in a stressed material. This energy release causes stress waves to propagate through the specimen. These acoustic...
Concrete Beam Testing with Optical Fiber Sensors
The use of an embedded multimode optical fiber to monitor curing and load-to-failure testing of a reinforced concrete beam has been investigated. The embedding process used to network...
A Critique of the Ultrasonic Pulse Velocity Method for Testing Concrete
The pulse velocity method is the most widely used ultrasonic nondestructive method for assessing concrete quality. However, it has been well established that the relation between ultrasonic...
Frequency Spectrum Analysis of Ultrasonic Testing Signal in Concrete
Description is given on high-speed sample apparatus connected with the CTS-25 low frequency ultrasonoscope and computer, the time domain of ultrasonic testing signal is transformed to...
Evaluation of Compressive Strength for High-Strength Concrete by Pulse Velocity Method
Development of compressive strength and pulse velocity for high-strength concrete from the age of 5 hours are studied in relation to cementitious material types and curing conditions....
Simulated Field Trials of Non-Destructive Concrete Test Methods for Highway Structures
The data presented results from a two year Strategic Highway Research Program investigation into suitable NDT methods for determining the early age, and residual strengths of highway structures....
Nondestructive Crack Identification by Acoustic Emission Analysis and Ultrasonic Frequency Response
Nondestructive evaluation (NDE) by the acoustic emission (AE) analysis and the ultrasonic testing (UT) on the spectral (frequency) response is studied to identify crack geometry. AE waveform...
Review of NPP Concrete Degradation Factors and Assessment Methods
Degradation of concrete in nuclear power plant (NPP) structures can be an age-related phenomena. Several research programs have been initiated by the U.S. Nuclear Regulatory Commission...
Pullout Testing of High-Strength Concrete Members
An experimental investigation of a high-strength concrete mixture was undertaken to measure and evaluate pullout and compressive strength properties. Two columns, a slab, and cylindrical...
Concrete Surface Characterization Using Optical Metrology
The displacement of the surface of a concrete specimen is measured as it cures using an optical method. This method, known as optical metrology, is one in which a line is projected onto...
Shrinkage Measurements in Composite Beam Slabs
When the concrete slab on a composite beam shrinks, it is restrained by the steel beam to which it is connected. Tensile stresses, as a result, are developed in the restrained concrete...
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Piles Over Problems Sites
It's increasingly difficult to find suitable space for construction in urban areas. Pile foundations can fill the void by making questionable and heavily regulated sites,...
Bayesian Reliability Updating of Existing Steel Girder Bridges
Bayesian statistics is used to update the reliability of existing composite steel girder bridges. A 60 ft. long simply supported superstructure is considered. The reliability for the ultimate...
Micromechanics and Effective Properties of Elastic Particulate Composites
A new micromechanical framework is proposed to investigate the effective mechanical properties of elastic particulate multiphase composites. Exact ensemble-volume averaged field equations...
Damage Dependent Micromechanics in Metal Matrix Composites
A computational approach is used herein to model the effects of processing induced thermal residual stresses on radial, hoop, and shear stresses at the fiber/matrix interface in a continuous...
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