Posts Tagged with Tuned Mass Dampers

Vibration Abatement of a Natural Gas Piping System Using Tuned Mass Dampers

Fluid/structure interaction and the operation of one of the natural gas compressors imparted dynamic forces onto one of the compressed natural gas piping systems of a power plant. The frequency of this dynamic perturbation happened to nearly match the first resonant frequency of the piping system, which in turn resulted in excessive resonant vibration of […]

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Passive and Active Pendulum Tuned Mass Dampers

Pendulum tuned mass dampers (PTMDs) are commonly used in adding damping to tall structures, including high-rise buildings, control and communication towers, stacks, etc. These multi-directional TMDs, which are made up of mass blocks suspended by steel cables or rods, can readily be tuned to the very low natural frequencies associated with the primary modes of […]

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Active Tuned Mass Dampers

The extent of vibration energy that a passive TMD dissipates as well as its effective frequency range (bandwidth) increase with an increase in the mass ratio of the TMD. In addition, the amount of internal damping built into the make-up of a passive TMD increases with the size of that TMD. The TMDs used in […]

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Self-Tuning of Tuned Dampers/Absorbers

The use of a tuned damper or a dynamic absorber in time-varying systems can only be effective if they are adjustable (semi-active) and continuously returned to the current resonant frequency of the system. Such dampers require a tuning algorithm that can automatically adjust the adjustable parameter of the tuned damper/absorber, e.g., the stiffness of the […]

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Semi-active Air-suspended Tuned Mass Damper

DEICON’s patented, semi-actively controlled, ‘air suspended tuned mass damper’ (TMD) uses one/multiple air spring(s) as both the restoring (resilient) and the energy dissipating (damping) elements. Feedback control is used to adjust the stiffness and damping of the air spring(s). The schematic of a tuned mass damper installed on a structure is shown in Figure 1. […]

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Vibration Abatement of a Monumental Staircase Using a Tuned Mass Damper

Following the evaluation of the dynamic attributes of a monumental staircase (in an upscale financial office building), one 500 lb tuned mass damper (TMD) was designed, fabricated, and shipped to the job site. Two views of the nearly completed staircase are shown in Figure 1. [Monumental, aesthetically pleasing staircases are getting incorporated more and more […]

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Vibration Control of an Overlook Using Tuned Mass Dampers

Hunter’s Point South Park is a breath-taking waterfront park located on the edge of the East River, in Western Queens, NY. The focal point of the park is Hunter’s Point South overlook, a beautiful cantilevered platform that offers unobstructed views of the New York skyline. The Overlook’s rather low fundamental frequency (3.5 Hz) combined with […]

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Vibration Control of a Concrete, Cantilever Pier Using Tuned Mass Dampers

Grant Street Pier, the focal point for “The Waterfront” development in Vancouver, WA is an attractive, triangular, post-tensioned concrete deck overhanging the water by 90 feet providing an expansive view of Columbia River. A cable system and 80-foot-tall mast support the deck. Since the pier is intended for visitors walking on it as well as […]

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Multi-mode vibration Control of a Floor System Using Tuned Mass Dampers

The composite floor system of a large multipurpose room on the third floor of the admission building at a state university exhibited noticeable vibration caused by walking. The composite floor system consists of three long and narrow bays. The vibratory attributes of the floor system established by numerical analyses and measurement revealed the presence of […]

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Vibration Control of an Office Floor System Using Tuned Mass Dampers

Foot traffic (walking) resulted in a vibration of the composite floor system on the 11th floor of an office building. The make-up of the floor system is slab construction consisting of 3.25-inch lightweight concrete fill on 2” deep, 20 gauge composite steel deck with the typical bay sizes of 30 ft x 30 ft and […]

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