scholarly journals Vibration Isolation of Existing Buildings in Microvibration Traffic Environment

2019 ◽  
Vol 2019 ◽  
pp. 1-13
Author(s):  
Qian Xia ◽  
Wen-jun Qu ◽  
Yi-qing Li ◽  
Jin Zhao
Keyword(s):  
Vibration Isolation ◽  
Theoretical Calculations ◽  
Residential Buildings ◽  
Isolation Effect ◽  
Slab Thickness ◽  
Filling Material ◽  
Construction Technology ◽  
Existing Buildings ◽  
Isolation System ◽  
The Impact

In order to explore the impact of traffic environmental microvibration on buildings, this paper studies indoor vibration isolation, a method applicable to existing buildings. The vibration isolation scheme is designed based on the residential buildings adjacent to metro lines in Shanghai. By using the dynamic theory, the effective range of vibration isolation stiffness is analyzed. The effectiveness of the indoor vibration isolation method is verified through theoretical calculations and comparison of field measurements before and after isolation. A detailed numerical model is established to analyze the indoor isolation and the effect after parameter optimization from the slab thickness, filling material, and isolator stiffness. The results show that the isolation effect is proportional to the thickness of the total slab thickness of the isolation system and inversely proportional to the stiffness of the isolator. And when concrete is used as the filling material, the isolation effect is best. The isolation effect of the midspan position is better than that of the wall-floor junction. The vibration isolation effect is more obvious after the parameters are optimized. With its convenient construction technology, short cycle, and low cost, this method is worth promoting.

The Vibration Isolation Effect Research of the Floating Raft Isolation System Based on the Adjustable Flexibility of Foundation

2013 ◽  
Vol 819 ◽  
pp. 115-119 ◽  
Author(s):  
Hui Wang ◽  
Ze Yu Weng ◽  
Gan Xiang ◽  
Bo Lu ◽  
Hong Gang Ding ◽  
...  
Keyword(s):  
Vibration Isolation ◽  
Test System ◽  
Isolation Effect ◽  
Isolation System ◽  
Elastic Beams ◽  
Floating Raft ◽  
Marine Engineering ◽  
Flexible Foundation ◽  
The Relationship ◽  
Theoretical Results

The floating raft isolation system is widely used in the field of marine engineering for its vibration isolation effect. Along with the application of light thinning structure of the ship, the flexibility of foundation of floating raft isolation system makes the vibration isolation effect vary widely between the practical floating raft isolation system and its theoretical results. In order to research the vibration isolation effect of the floating raft isolation system on different flexibility of foundation, the floating raft isolation system with flexible foundation is designed in this paper, and the adjustable flexibility of foundation is achieved by using elastic beams. With simulation and analysis of test system in ADAMS, the results of the relationship between flexibility and vibration isolation effect are obtained.

scholarly journals Vibration-Isolation Performance of a Pile Barrier in an Area of Soft Soil in Shanghai

2020 ◽  
Vol 2020 ◽  
pp. 1-27
Author(s):  
X. F. Ma ◽  
M. Y. Cao ◽  
X. Q. Gu ◽  
B. M. Zhang ◽  
Z. H. Yang ◽  
...  
Keyword(s):  
Numerical Model ◽  
Vibration Isolation ◽  
Soil Layer ◽  
Isolation Effect ◽  
Normal Operation ◽  
Vibration Source ◽  
Filling Material ◽  
Vibration Measurements ◽  
Pile Diameter ◽  
Environmental Vibration

Environmental vibration caused by traffic can affect the normal operation of precision instruments, and vibration-isolation measures should be taken to reduce such negative effects. The engineering background of this paper is a hard-X-ray tunnel under construction in Shanghai, China. First, field vibration measurements are used to study the characteristics of the ground traffic, maglev, subway, and other vibration sources near the tunnel, as well as the laws governing the propagation of vibration waves in the surface and soil layer. The finite-element modelling is then used to establish a two-dimensional numerical model for the field conditions, and the numerical results are compared with the field vibration measurements to validate the applicability of the numerical model for assessing the effects of environmental vibration. Finally, how the parameters of a pile-barrier vibration-isolation system, a vibration-isolation measure used widely for tunnels, influence its performance is studied. The results show the following: with increasing distance from the vibration source, the amplitude of the vibration acceleration decreases gradually, and the high-frequency part of the vibration wave is attenuated rapidly, whereas the low-frequency part is attenuated very little. The vibration-isolation effect of the pile barrier is directly proportional to the elastic modulus of the pile body, the pile length, and the hollow ratio of the pile, and inversely proportional to the stiffness of the filling material. The pile diameter, pile row number, and row spacing have little influence on the vibration-isolation effect. Increasing the pile diameter attenuates the acceleration amplitude somewhat around 10 Hz but has no effect on it around 5 Hz. Overall, the present numerical method is well suited to evaluating environmental vibration problems.

scholarly journals Application Of Sustainable Design Principles To Increase Energy Efficiency Of Existing Buildings

2014 ◽  
Vol 61 (3) ◽  
pp. 167-177 ◽  
Author(s):  
B. Mansoury ◽  
H. R. Tabatabaiefar
Keyword(s):  
Energy Efficiency ◽  
Thermal Performance ◽  
Sustainable Design ◽  
Residential Buildings ◽  
Construction Materials ◽  
Design Principles ◽  
Existing Buildings ◽  
Performance Study ◽  
Improve Energy Efficiency ◽  
The Impact

Abstract This study investigates the effectiveness of different energy retrofitting techniques and examines the impact of employing those methods on energy consumption of existing residential buildings. Based on the research findings, the most effective and practical method of retrofitting has been proposed in order to improve energy efficiency of existing buildings. In order to achieve this goal, an existing residential building has been simulated in FirstRate 5 software so as to determine the existing thermal performance of the building. Afterwards, considering sustainable design principles, different insulation layers, glazing, and construction materials have been employed to conduct a comprehensive thermal performance study. Based on the research outcomes, the best technique for increasing energy efficiency of existing buildings and reducing their environmental impact and footprint has been identified and proposed for practical purposes.

scholarly journals Application of a Thermal Performance-Based Model to Prediction Energy Consumption for Heating of Single-Family Residential Buildings

Energies ◽  
2022 ◽  
Vol 15 (1) ◽  
pp. 362
Author(s):  
Tomasz Szul
Keyword(s):  
Energy Consumption ◽  
Energy Demand ◽  
Residential Buildings ◽  
Simple Procedure ◽  
National Level ◽  
Heat Consumption ◽  
Construction Technology ◽  
Existing Buildings ◽  
Single Family ◽  
Model Quality

Energy consumption for heating of single-family residential buildings is a basic item in energy balance and significantly affects their operating costs. Accuracy of heat consumption assessment in existing buildings to a large extent determines the decision on taking actions aimed at heat consumption rationalization, both at the level of a single building and at regional or national level. In the case of energy calculations for the existing buildings, a problem often arises in the form of lack of complete architectural and construction documentation of the analyzed objects. Therefore, there is a need to search for methods that will be suitable for rapid energy analysis in existing buildings. These methods should give satisfactory results in predicting energy consumption when there is limited access to data characterizing the building. Therefore, the aim of this study was to check the usefulness of a model based on thermal characteristics for estimating energy consumption for heating in single-family residential buildings. The research was conducted on a group of 84 buildings, for which the energy characteristics were determined based on the actual energy consumption. In addition, information was collected on variables describing these buildings in terms of construction technology and building geometry, from which the following were extracted for further calculations: cubic capacity, heated area, and year of construction. This made it possible to build a prediction model, which enables the application of a fast, relatively simple procedure of estimating the final energy demand index for heating buildings. The resulting calculations were compared with actual values (calculated from energy bills) and then evaluated according to the standards for evaluating model quality proposed by the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE). In this way, it was possible to determine whether, in the absence of building documents, the indicative method gives good results when estimating the energy demand for heating single-family residential buildings.

The impact of the energy performance regulations’ updated on the construction technology, economics and energy aspects of new residential buildings: The case of Greece

2017 ◽  
Vol 155 ◽  
pp. 225-237 ◽  
Author(s):  
Athina G. Gaglia ◽  
Aikaterini G. Tsikaloudaki ◽  
Costantinos M. Laskos ◽  
Evangelos N. Dialynas ◽  
Athanassios A. Argiriou
Keyword(s):  
Residential Buildings ◽  
Energy Performance ◽  
Construction Technology ◽  
The Impact ◽  
Of Greece ◽  
Energy Aspects

Optimal Controller for Active Vehicle Suspension Disturbed by Sinusoidal Signals

2016 ◽  
Vol 248 ◽  
pp. 127-134
Author(s):  
Marek Sibielak ◽  
Waldemar Rączka ◽  
Jarosław Konieczny ◽  
Janusz Kowal
Keyword(s):  
Performance Index ◽  
Vibration Isolation ◽  
Optimal Solution ◽  
Vehicle Suspension ◽  
Isolation System ◽  
Control Laws ◽  
Control Time ◽  
Sinusoidal Signals ◽  
System Frequency ◽  
The Impact

The problem of optimal control of systems disturbed by sinusoidal signals for infinite control time is considered in the paper. The control laws described in [1] is base of a modified mean-square performance index with an infinite control time. The performance index was formulated in such a way that each sinusoidal component corresponds to a separate weight matrix. This allows energy constraints on the control signals to be differentiated based on frequency. An optimal solution to the optimization problem was found. In the paper the problem of the impact of time on the identification of sinusoidal disturbance on vibration isolation system frequency characteristic. The controller was synthesized for slow-active vehicle suspension [2,3]. The model of suspension, synthesis of the controller and implementation of the system was described. The results of simulations of the designed vehicle active suspension system are presented.

A Vibration Study of a Hydraulically-Actuated Legged Machine

2010 ◽  
Author(s):  
Emanuele Guglielmino ◽  
Ferdinando Cannella ◽  
Claudio Semini ◽  
Darwin G. Caldwell ◽  
Nestor Eduardo Nava Rodri´guez ◽  
...  
Keyword(s):  
Vibration Isolation ◽  
Legged Robot ◽  
Isolation System ◽  
Vibration Isolation System ◽  
Hydraulically Actuated ◽  
Modes Of Vibration ◽  
Pros And Cons ◽  
Heavy Loads ◽  
Multi Body ◽  
The Impact

This paper presents a study on the impact of the vibration on a hydraulically-actuated legged robot designed for outdoor operations. The choice of using hydraulic actuation in lieu of electric actuation as is common in robotics has been driven by the need to cope with heavy loads and respond swiftly to external inputs and disturbances. However in such machines hydraulically-induced vibration (fluid borne noise and structure borne noise) is a major issue. Volumetric pumpmotor assembly is a primary cause of vibration. These are transmitted to the robotic structure, which has been designed as light as possible to minimise the robot’s total weight and power consumption and make it more agile. Initially a multi-body analysis of the robot was carried out to select an appropriate vibration isolation system. Subsequently a numerical and experimental modal analysis was carried out on the structure. The latter was carried with modal hammer tests and pump running tests. This has allowed identifying the main modes of vibration of the structure. The pros and cons of this approach are described and areas of improvements identified.

STUDY OF THE VIBRATION ISOLATION SYSTEM OF MARINE POWER PLANTS WITH A 5AL 25/30 DIESEL DRIVE

Akustika ◽  
2021 ◽  
pp. 112
Author(s):  
Minas Minasyan ◽  
Armen Minasyan ◽  
Kyaw Thet Naing
Keyword(s):  
Experimental Study ◽  
Diesel Engine ◽  
Power Plants ◽  
Vibration Isolation ◽  
Field Studies ◽  
Absorption System ◽  
Isolation System ◽  
Vibration Isolation System ◽  
Vibration Isolators ◽  
The Impact

The article is devoted to the study of the support and side stop vibration isolation system of two marine power plants DGA- 500 with a 5AL 25/30 drive diesel engine, in which a hypothesis is put forward about the imperfection of the shock absorption system. The purpose of the research is to substantiate the imperfection of the support and side stop vibration isolation system of marine power plants with a 5 AL 25/30 drive diesel engine. The confirmation of this hypothesis and the achievement of this goal is justified on the basis of presentation of the results of field studies on the project’s courts B437/11 and the personal presence during the preparation of DGA-500 to repair at the shipyard. For the use of unbalanced engines as a drive for ship power plants, the authors, on the basis of a full-scale experimental study and analysis of known works, recommend initially assessing the possibility and purpose of depreciation of the unit according to the Katz unbalance criterion [1]. The objective of fixing the unit with diesel 5AL 25/30 on the criterion of imbalance Katz is soundproof, and the calculation of depreciation should be based on the impact of side stop vibration isolators. A significant improvement is recommended to the support 36-40 and side stop 41-52 vibration isolation system, elastic pipe fittings 8, support frame 2 and turbocharger bracket 4 (Fig. 1).

Performance Evaluation of the Vehicle Vibration Safety in the Frequency Domain

2018 ◽  
pp. 1-21 ◽  
Author(s):  
L. F. Zheglov ◽  
A. B. Fominykh
Keyword(s):  
Dynamical System ◽  
Mathematical Modelling ◽  
Frequency Domain ◽  
Vibration Isolation ◽  
Statistical Linearization ◽  
Safety Criterion ◽  
Isolation System ◽  
Time Domains ◽  
The Impact ◽  
Disturbing Action

The article deals with mathematical modelling of the nonlinear system of vehicle vibration isolation. It is known that this problem can be solved both in the frequency and in the time domains. To assess the adequacy of the results obtained, a computation algorithm for evaluated performances in the frequency domain is considered at the first stage of the study. In this case, a statistical linearization procedure is used through the example of a spatial dynamic model equivalent to the primary and secondary vibration isolation systems of a two-axle vehicle (a dynamical system with seventeen degrees of freedom). A matrix method for determining the frequency characteristics of a given dynamical system is used, and the adaptation features of four known methods of statistical linearization are shown. The article focuses attention on advantages of the system frequency representation when testing it and determining the main parameters. In order to generalize the conclusions when comparing the calculation results in the frequency and time domains, computations were performed for two variations of the intensity of the disturbing action. Such a "hard-line" approach enables us to determine the impact of the nonlinear characteristics of the vibration isolation system components on the output integral and separate-frequency performance estimates, taking into account a vehicle's safety criterion.The simulation results of this system show different values of the integral and separate-frequency estimates for all four methods of statistical linearization, regardless of the intensity of disturbing action and the loss probability of contact between the tire and the wearing surface from 5% to 30%. The calculation data obtained allow comparing with the mathematical modelling results of the given dynamical system in the time domain and defining position according to recommendation of the statistical linearization method.

System Identification Based on Recursive Least Square Method for the Magnetic Suspension Active Vibration Isolation System

2012 ◽  
Vol 150 ◽  
pp. 105-110 ◽  
Author(s):  
Bei Bei Yang ◽  
Ye Fa Hu ◽  
Guo Ping Ding
Keyword(s):  
System Identification ◽  
Transfer Function ◽  
Vibration Isolation ◽  
Isolation Effect ◽  
Isolation System ◽  
Vibration Isolation System ◽  
Transfer Function Matrix ◽  
Active Vibration ◽  
System Transfer Function ◽  
Function Matrix

In this paper, we use recursive least squares method for magnetic single layer vibration isolation system identification to get the system transfer function matrix. By considering the fitting degree, pole-zero, the step response to adjust the order of model and noise structure for optimizing the model Identification. Applying the system transfer function matrix to the magnetic active vibration control system to improve the isolation effect. The results showed that: significantly improved isolation effect, verify the validity of this identification model for magnetic single isolation system.

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