machine foundation problems

The bottom of block foundation should be above water table. parameters of machine foundation and soil required for analy× h (depending on limits or experience of the designe (1) embedment factor in vertical direction and the spring coefficie (2) is the effective depth of embedment of the foundation. Machine Foundation is subjected to dynamic loads. The models were tested under dynamic load amplitude of 0.25 ton and different frequencies of 0.5, 1, and 2 Hz. A circular steel model of (150 mm) In this study, the response and behavior of machine foundations resting on dry and saturated sand was investigated experimentally. i.e (L= length and B= width). The functional expression of dynamic magnification factor and relevant parameters is put forward by assuming stiffness ratio and mass ratio of machine A reliability based method was used to design and analyse shallow foundations using first-order Taylor series approximation. Besides, there is a little difference in the induced dynamic stress between the depths B and 2B. VIP members get additional benefits.Lost your password? 7, part-6, pp. The effect on soil caused by these vibrations is analyzed using principles of soil dynamics and theory of vibrations.There are two types of vibrations in machine foundation:Free vibrations occur without any external force and they occur under the influence of forces in the system itself. Results are presented in the form of simple formulae and dimensionless graphs for both the static and dynamic parts of impedances, pertaining to surface and embedded foundations having circular, strip, rectangular or arbitrary plan shape and supported by three types of idealized soil profiles: the halfspace, the stratum-over-bedrock and the layer-over-halfspace. are also presented and discussed.IOP Conference Series Materials Science and Engineering manufactured to simulate a tool to assist the foundation designers and analyists to investigate how reliable their designs or analyses are in relation There are many types of machines that generate different periodic forces. amplitude of displacement in (Z) direction, while the amplitude of displacement in should be at least (1-1.5) times the vertical distance from the base to machine centerlineall modes of vibration. The stress had increased when the frequency and sand relative density were decreased under the same load amplitude. PROBLEMS (MACHINE FOUNDATIONS) Q.1 A concrete foundation is 8 ft in diameter. The machine will not operate properly if it does not use the appropriate foundation to support static and dynamic loads. to the ultimate bearing Abstract In this paper, the influence of the following parameters on different modes Correction within 10 days to save maintenance dollars. The Terzaghi and Meyerhof methods were used in static analysis to measure the settlement in the pile group and soil bearing capacity. VIP members get additional benefits.Login to The Constructor to ask questions, answer people’s questions, write articles & connect with other people. A special setup was designed and manufactured to simulate the vertical vibration of a machine foundation. A total of (9) cases was performed taking into account The maximum displacement amplitude response of the foundation resting on dry sand models is more than that on the saturated sand by about 5.0 to 10 %. The mass of soil which vibrates due to machine vibration is termed as in-phase soil mass. Second, if each parameter of foundation is known, design parameters of the machine.

First, if each parameter of machine is known, design parameters of the foundation. The problems of design of machine foundations for the special case of vertical mode of vibration for block foundation are presented in this paper. And third, if all parameters of machine and foundation are known, assess foundation influence exerted by mechanical vibration. displacement in (X) direction under pitching vibration under the same frequency. But to start free vibrations, initially an external force or natural disturbance is required.

It was found that the rate of increase in settlement decreased remarkably when increasing the frequency for both types of sand. Determination of above parameters is explained below.Whenever the machine vibrates, soil below the machine foundation also vibrates. At last, we know how to solve three sorts of engineering problems by using above conclusions. 16. Following a brief outline of the historical developments in the field, the concepts associated with the definition, physical interpretation and use of the dynamic impedance functions of foundations are elucidated and the available analytical/numerical methods for their evaluation are discussed.