Vibratory Machine Foundation Design: When to Perform a Dynamic Analysis

AbstractIn this study the dynamic response of a machine-foundation-soil system was investigated experimentally and theoretically. The objective of this work is to analyze the effects of the water table fluctuations in the soil on the response of the foundation and machine subjected to dynamic loads at frequencies ranging from 30 to 50 Hz. A physical model test was developed to simulate a machine-foundation-soil system, with measurements of the machine vibrations and the shear wave velocity of the soil. It is found that the water level produced significant changes in the shear wave velocity of the soil and, thus, in the natural frequencies of the system. For a fully saturated soil the vibration levels increased due to a working condition near resonance. The results showed a good agreement between the experimental vibration measurements and the predictions based on the theory used in foundation design, when considering the appropriate soil parameters. It is concluded that proper estimation of soil parameters is of high importance in the design process of machine foundations.

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Study of vibration and dynamic analysis of machine foundation in ansys for deferent geometry

INTERNATIONAL JOURNAL OF STRUCTURAL ENGINEERING AND ANALYSIS ◽

10.37628/jsea.v1i1.684 ◽

2021 ◽

Author(s):

Anagha Bhumkar ◽

R.S Patil

Keyword(s):

Dynamic Analysis ◽

Machine Foundation

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Underground Space Form Design of Large Centrifugal Shaker System and Analysis of Machine Foundation Vibration

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.238.795 ◽

2012 ◽

Vol 238 ◽

pp. 795-798

Author(s):

Yong Zhi Wang ◽

Yun Long Wang ◽

Zhuo Shi Chen ◽

Xiao Ming Yuan

Keyword(s):

Earthquake Engineering ◽

Seismic Waves ◽

Elastic Half Space ◽

Test Method ◽

Underground Space ◽

Foundation Design ◽

Space Forms ◽

Machine Foundation ◽

Geotechnical Earthquake Engineering ◽

Foundation Vibration

Centrifugal shakers are accounted the most effective and the most advanced test method of geotechnical earthquake engineering and soil dynamics, for a unique ability of exerting dynamic loads of sine waves and seismic waves on models while the same gravity stress as prototype is produced. Large centrifugal shakers are necessary to countries of frequent earthquake occurrences, but no one has been built in China. As state-of-the-art test equipments, its construction absolutely has many challenges. In the machine foundation design, its underground space employed a narrow rectangle as usual can’t satisfy the required space of facilities, while the imbalance force of equipments against foundation stability is inherently high. For no relevant research findings can be available, the paper states the general layout of a large centrifugal shaker and the fiendish problems between two space forms. By theories of mass-spring-damper and elastic half-space, two foundation vibration mathematical models for large centrifugal shakers are proposed. The calculation results of both underground space forms show that a round space meeting the required space of facilities doesn’t significantly increase foundation vibration, and is more ideal. Moreover the view of a narrow rectangular underground space more stable to large centrifugal shakers by experience is not true.

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Analysis and dynamic behavior of portal structures due to reciprocating machine

IJTI (International Journal Of Transportation And Infrastructure) ◽

10.29138/ijti.v3i2.1063 ◽

2020 ◽

Vol 3 (2) ◽

Author(s):

Essen Donald ◽

Dwi Pratama Andreas

Keyword(s):

Free Vibration ◽

Dynamic Analysis ◽

Vibration Analysis ◽

Free Vibration Analysis ◽

Reciprocating Compressor ◽

Machine Foundation ◽

Final Project ◽

Reciprocating Engine ◽

Long Time ◽

Engine Start

reciprocating engine consists of two driving parts, piston and rotor, when the engine start these two parts move with a certain frequency, resulting in vibrations in the structure. dynamic analysis of the structure aim to find out how the structure behaves due to vibrations generated from the machine, whether the structure is safe for the machine and humans around the machine due to the amplitude of displacement, velocity, and displacement from structure. This dynamic analysis is carried out with the help of SAP 2000 v20.20 software with a dynamic load in the form of a reciprocating compressor operating with a frequency of 49.16 Hz. In this final project, the machine foundation uses a table top type with 1x1.7 m column dimensions and 1.3x1.6 m beams. From the free vibration analysis, the result is a natural frequency structure, from the first ten modes the structure is declared safe from resonance However, in this study the displacement and velocity of structures that occur in the zone B & C while the acceleration into the safe category based on applicable standards. This means that the structure is safe for humans who are around but are not safe for the product and the machine itself if it operates for a long time continuously.

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