Expertise Facility Types

Research tagged "concrete damping"

Temperature and Frequency Effects on Properties of Polymer-Modified Concrete

The dynamic elastic modulus and damping of concrete made from ordinary portland cement (OPC) remain relatively constant over the significant ranges of temperatures and frequencies that might be encountered in normal application.  However, this is not the case with polymer-modified concrete (PMC).  This paper presents results of an experimental study examining the role of temperature […]...
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Experimental Determination of Modal Damping in Concrete Beams

An approach using experimental modal analysis (EMA) is presented for measuring the material damping properties of concrete beams.  This approach, now popular in mechanical and aerospace engineering, uses hammerblow excitation and frequency-domain analysis to estimate resonance frequencies and modal damping.  Damping properties quantified in this manner are compared to results obtained by traditional methods, which […]...
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Reducing Floor Vibrations: A polymer admixture provides increased damping in concrete

This “product note” in a trade publication discusses a polymer admixture designed to increase concrete’s damping properties and therefore increase the decay of impact-induced vibrations. The liquid additive is similar to styrene-butadiene rubber (SBR) admixtures that are commonly used in pavement to improve durability, but has been modified by adding vegetable gum in the suspension.  […]...
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Can Vibration be Controlled with Concrete Damping?

Vibration has long been recognized as a contaminant in a fab. The vibrations can come from many sources both within and exterior to the facility. For quite some time, designers and consultants have discussed means by which future vibrations from “unplanned” sources might be mitigated via design or construction. This article presents one possible approach […]...
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Instalaciones para nantecnología

(In Spanish) This article explores nanotechnology from the perspective of a member of the advanced technology building design team—the structural dynamicist—and focuses on concrete, often the structural material of choice for these facilities. First, it shows how one application in nanotechnology led to research addressing some of concrete’s dynamic properties. Then it discusses some of […]...
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A “Toolbox” of Damping Treatments for Concrete Structures

The paper presents measures by which significant changes in the damping of concrete may be achieved.  A variety of alterations in mix design were examined experimentally, and the most effective treatments involved the use of polymer admixtures.  Significant changes in damping were associated with the use of several types of styrene-butadiene rubber (SBR) latex, ethyl-vinyl-acetate […]...
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Damping Properties of Polymer-Modified Concrete

The paper presents selected results from a broad study undertaken to explore means by which one might increase damping in concrete, which is relatively low—except for when the concrete is rather young—and essentially independent of temperature and frequency.  The most easily implemented approach involves the addition of latex admixtures to the concrete, resulting in a […]...
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Construction of Nanotechnology Facilities

The sophisticated working environments required for nanotechnology facilities pose big challenges to their designers and constructors. Environmental requirements of a nanotechnology facility may include temperature and humidity control, air cleanliness, biohazard containment, limits on electromagnetic fields, special electrical power conditioning, and vibration and noise control. Most of these design aspects have evolved from the special […]...
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