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This study examines the influence of the interference on the dynamic response of two active machine foundations using the finite element analysis. The finite element model has been built carefully to ensure that the finite element model extend, and the mesh size do not influence the obtained results. Furthermore, the methodology of the finite element analysis has been verified using well-known and robust analytical solutions of wave propagation and machine vibration. Loose sand, medium sand, and dense sand and a vibration frequency range of 0.5–20.0 Hz have been considered in the analyses. The results showed that the interference of two active machine foundations remarkably increases the dynamic settlement with a percentage increase range from 1 to 77%. This percentage increase declines as the frequency of vibration or the distance between the foundations increases and rises as the soil stiffness increases. It was also found that the critical distance after which the interference effect terminates depends on the frequency of vibration and the stiffness of the soil, where the critical distance increases as the frequency of vibration declines or as the stiffness of the soil increases. Finally, a methodology has been proposed based on the results of the analyses to implicate the effect of interference in the calculation of the dynamic settlement.

The current investigation examines the influence of footing shape, the base area of footing ( A ), the mass of footing-machine assembly ( m ), and eccentric force settings ( m e e ) on the dynamic response and performance of machine foundation systems. Five different footing configurations are employed to perform field block vibration tests involving three square, one circular and one rectangular footing. The experiments are performed at the geotechnical field laboratory of IIT Kanpur, India (N26°30′59.0892″, E80°13′51.6888″). The accuracy and reliability of the experimental results are endorsed by the results obtained from the mass-spring-dashpot (MSD) analysis. In addition, an artificial neural network (ANN) model is created to anticipate the dynamic behaviour of the soil-foundation system. A thorough parametric study demonstrates the efficacy of the developed ANN model. It is revealed from the investigation that the stiffness ( k ) and the damping ratio ( D ) of the soil for square foundations increase by 7% and 3%, respectively, with a 40% increase in A . Similarly, the circular foundation exhibits 7 and 3% higher k and 4 and 3% higher D than those obtained for square and rectangular foundations, respectively. For square foundations, a 24% enhancement in m leads to a 42 and 4% increase in k and D , respectively. In contrast, for circular and rectangular foundations, a 13% increase in m results in a 27 and 19% increase in k and D , respectively. In this study, experimental testing, analytical validation, and ANN modelling provide insight into the response of machine foundations under various operating conditions. The results of this study can be utilized to optimize the design of machine foundations.

This paper explains the behavior of harmonically loaded machine foundations supported by geogrid-reinforced soil beds using multi-model approaches, such as experimental, numerical, analytical, and artificial neural network (ANN) modeling techniques. Field block vibration tests are performed on a foundation bed measuring 1.47 m × 1.47 m × 0.65 m, prepared on the soil at IIT Kanpur, India [N26° 30′ 59.0892″ (latitude), E80° 13′ 51.6888″ (longitude)]. Two different reinforced cement concrete (RCC) footings of sizes 0.55 m × 0.55 m × 0.2 m and 0.65 m × 0.65 m × 0.2 m are employed in this investigation. The tests are performed at three different eccentric force settings considering three testbeds: unreinforced, single-layer and double-layer geogrid reinforced beds. Geogrid layers reduce resonant amplitude and dynamic shear strain while simultaneously improving resonant frequency, system characteristics and dynamic soil properties. Further, the experimental results are compared with those obtained from the finite element and mass-spring-dashpot analysis. The displacement amplitude of footings is also predicted at different frequencies using ANN modelling to endorse the authenticity of the study. Encouraging agreements can be observed among various modeling approaches considered in this study.

This paper presents a comprehensive review of seismic hazard assessment in machine foundation design and highlights key research directions for future studies. The review includes a detailed analysis of existing literature, that covers a wide range of subjects associated with seismic analysis and design of machine foundations. It begins with an overview of the seismic hazard assessment evaluation procedure and the various factors that influence it, such as soil properties, machine stiffness, and earthquake excitation. Then it discusses the key challenges associated with the design and seismic analysis of machine foundations, including the impact of dynamic loads and soil-structure interaction. Following the analysis of the current research, the paper identifies several important research directions for future studies. These include the development of more accurate seismic hazard assessment methodologies, using sophisticated numerical modeling methods. The paper also emphasizes the need for more comprehensive experimental studies to validate the numerical models and better understand the behavior of machine foundations under seismic loads. In brief, the paper provides a comprehensive review of the current state of knowledge in seismic hazard assessment in machine foundation design and highlights the importance of future research to proceed in this field.

The dynamic reaction of the natural type of retaining wall is quite complex. Wall development and pressure rely upon the reaction of the soil underneath a retaining wall and the reaction of the backfill. The greater part of the present knowledge of the dynamic reaction of the wall has originated from the model test and numerical analysis. This paper aims to know the behavior of the retaining wall and the backfill. Also, under the effect of machine foundation, numerical modeling is used concerning a method of finite element. Two amplitudes of machine foundation subjected to three frequencies were used. The model used in the finite element was the linear elastic model (LE) for foundation and the Mohr-Coulomb model (MC) for soil. The results of this analysis for the amplitude of 25 kPa, the lateral displacement was 75% more than the active for the case of the amplitude of 40 kPa, the lateral displacement was 125% more than the active, and for the case of the velocity of 30 mm /sec very far higher than the maximum permissible velocity is 2.5 mm/sec and the acceleration was decreased by 52% between machine foundation and retaining wall.

Currently, the construction of machine tool foundations is a complicated and lengthy procedure with a limited flexibility. In this paper, we present a novel system for constructing machine tool foundations that replaces the need for concrete or concrete-polymer hybrids with a low melting point (LMP) alloy. The system uses a hot bath method to maintain the LMP alloy grouting in liquid form. A fixing device is used to control the embedded depth and positional accuracy of the foundation bolt assembly. The grouting material is injected into the foundation pit by a filling device. This can be extracted from the foundation pit in a later stage with the aid of a recycling device, enabling new machine tool foundations to be manufactured by reusing the LMP alloy grouting material. A prototype was built to test the proposed design. The results show that the system can construct machine tool foundations in a single application, without the delays associated with concrete-based construction, lowering both the economic and environmental cost.

In this paper, the influence of the following parameters on different modes of vibration response of model footings on sand is studied: (vertical, rocking and pitching load amplitude and frequency). To achieve the objective of this study, the model footing was selected to be rectangular footing with an aspect ratio (L/B= 1.33) i.e (L= length and B= width). A physical model was manufactured to simulate a steady-state harmonic dynamic load applied at different operating frequencies with the same load amplitude (0.5 ton). A total of (9) cases was performed taking into account different parameters. The loading frequency ranged from (0.5) to (2) Hz and the footing was rectangular with an aspect ratio (L/B = 1.33). The soil type used was dry sand having a relative density of (50%). The behavior of the soil underneath the footing was examined by measuring the strain using a shaft encoder and the amplitude of displacement using a vibration meter. It was found that the change in vibration mode made little effect of the final strain values under the same frequency and the amplitude of displacement in (Z) direction, while the amplitude of displacement in (Y) is higher, occuring under rocking vibration and higher value amplitude of displacement in (X) direction under pitching vibration under the same frequency.

The manufacturing accuracy of modern machine tools strongly depends on the placement of the machine tool structure on the factory’s foundation. Civil engineering knows a variety of foundation types and factory planners must carefully consider local circumstances such as the size and the properties of the regional subsoil as well as the individual requirements of machine tools. Two of the major reasons for the effect of the foundation onto the machining accuracy are the added stiffness and the increased mass from the installation site’s foundation. A change of these characteristics greatly affects the dynamic characteristics of the overall machine tool and therefore also the machining dynamics. Although some general rules and guidelines exist for the design of foundations, their dynamic interaction with the supported precision machine tool structures is not well understood yet. This paper presents a series of measurements on two different types of machine tool foundations and highlights the characteristic differences in their dynamic interaction. It also proposes a novel approach to validate the conclusions with the use of foundation and machine tool scale models. These results can serve factory planners of precision targeting shop floors as a valuable guide for deciding on a suitable foundation for lowering the individual machine tool vibrations and/or reducing the dynamic interaction between closely located machine tools.

This paper emphasizes on the dynamic interaction of two closely spaced embedded square or rectangular foundations under the action of machine vibration. One of the foundations is excited with a known vibration source placed on the top of it, called the active foundation. The objective is to study the effect of dynamic motion of the active foundation on the nearby passive foundation through a layered soil medium. The analysis is performed numerically by using the explicit finite difference code FLAC 3D . The soil profile is assumed to obey the Mohr–Coulomb yield criteria with non-linear failure envelope. The analysis is performed under sinusoidal dynamic loading with varying amplitude. Under the dynamic excitation, the settlement behavior of the interacting foundations is studied by varying the spacing between the foundations. In addition, the variation of vertical normal and shear stress developed beneath the interacting foundations is also explored. The present theoretical investigation indicates that the settlement and vertical normal stress below the active foundation is generally found to be higher than that obtained for the passive foundation, whereas the shear stress response below the foundations follows the reverse trend.

Faced with the constantly increasing requirements for machine efficiency and reliability, designers have to pay attention to every detail, including machine foundation. Possible outage costs due to foundation damage can easily exceed the costs of design and construction of the foundation. This paper presents a novel and systematic procedure for finding an optimal design of reinforced concrete columns of the spring mounted machine foundation subjected to dynamic loads. The proposed approach assumes considerably decoupled natural modes of the critical structural members which can be optimized as simplified analytical models. It includes the following steps: FE modal analysis of the complete structure, identification of expected dynamic excitation, determination of the critical structural members, optimization of the corresponding analytical models and verification by FE modal analysis of the complete optimized structure. Turbine-generator-foundation structure was employed as an illustrative example. Operating speeds of the turbine and the generator and their higher order harmonics are taken as a critical dynamic excitation. Therefore, avoiding possible resonance region became the design objective, while the design variables were dimensions of the foundation columns cross-section. Lower and upper bounds of the design variables are determined on the basis of structural stability and space limitations regarding condenser and other auxiliary components of the turbine-generator system. The results of the analyzed example confirm that the optimization was successfully performed, since the optimized dimensions of the columns yielded natural frequencies outside the critical frequency range.