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The objective of this study is to evaluate of the environmental impacts associated with the manufacturing process of a cork floating floor, produced in Portugal, in order to identify the most significant stages and processes (hotspots) with the aim of improving the manufacturing process and the sustainability of the product.Life Cycle Assessment methodology is used by applying a cradle-to-gate approach. The results show that the stage with the highest environmental impact is the assembling stage (where all the product’s components are assembled) mainly due to the production of high density fiberboard.Additionally, the present study discusses the currently hot and controversial issue of biogenic carbon considering its storage in products and emission delay. For this part of the study a cradle-to-gate approach was adopted and three leading methodologies were compared, namely, Greenhouse Gas Protocol Product Standard, Publicly Available Specifications 2050 and the International Reference Life Cycle Data System. The results show that the choice of methodology has an important influence on the results obtained both for biogenic carbon dioxide emissions and carbon storage. This highlights the need for the establishment of a common methodology for the calculation of biogenic carbon, not only for the homogeneity of the guidelines but also for the ease of comparing results. Keywords: Biogenic carbon, Cork flooring, Environmental impact, Life Cycle Assessment, Portugal

Floating floor structures installed with resilient materials are commonly used to reduce sound from floor impacts. Resilient materials minimize the transmission of vibrations by absorbing shock vibrations occurring on the upper part. The floor impact sound reduction performance of resilient materials is related to the dynamic stiffness, which is a physical characteristic of materials. However, the dynamic stiffness varies according to the increase in the loading time of the load that is installed on the upper part of resilient materials. The dynamic stiffness values increase with an increase in the loading time; an increased dynamic stiffness value decreases the vibration reduction effect. The present study focuses on a floor structure installed with resilient materials, and identifies the degree of reduction in floor impact sound insulation performance with the elapse of time. The insulation of sound from lightweight impact sound decreased with the elapse of time, whereas the heavyweight impact sound did not show significant changes.

Resilient materials are used to reduce vibration transmission in buildings, e.g. in floating floors designed to decrease the impact sound pressure level in the room below the floor. The performance of a floating floor can be estimated in advance knowing the dynamic stiffness per unit area of the resilient material, which is usually measured on a small sample according to ISO 9052-1. Thus, the reliability of results from ISO 9052-1 measurements is crucial. However, the published standard gives few indications on the measuring equipment and suggests measuring the resonance frequency of the fundamental vertical vibration of the test specimen and of the load plate by using either sinusoidal, white noise or pulse signals, considered as equivalent. In this work, a measuring apparatus following the ISO 9052-1 specifications with some hardware and software improvements is described. Then the scanty specifications about the excitation signal are complemented introducing two robust alternatives, compatible with the ISO 9052-1 prescriptions: the ESS (Exponential Swept Sine) and MLS (Maximum Length Sequence) signals. The two newly proposed signals are validated measuring the dynamic stiffness per unit area of different resilient materials, whose resonance frequency is estimated using the same measuring equipment and four different excitation methods: hammer generated impulses, white noise, ESS and MLS. The comparison shows that ESS and MLS signals, already in use since many years for other kinds of acoustic measurements, are viable alternatives to traditional techniques and may have advantages in term of repeatability, dynamic range, cleanness of the frequency response and background noise immunity.

This paper reports the test results of the floating floor system used to reduce the floor noise of apartment buildings. Recently, many soft resilient materials placing between the reinforced concrete slab and finishing mortar are used. The resilient material should not only reduce the floor impact sound vibration from the floor but also support the load on the floor. Thus, even if soft resilient materials satisfy the maximum limitation of light-weight impact sound and heavy-weight impact sound, these materials may not support the load on the floor. The experimental program involved conducting sixteen sound insulation floating floor specimens. Three main parameters were considered in the experimental investigation: resilient materials, loading location, and layers of floor. Experimental results indicated that the stiffness of resilient material significantly influenced on the structural behavior of floating floor system. In addition, the deflection of the floating concrete floor loaded at the side or coner of the specimen was greater than that of the floor loaded at the center of the specimen. However, the aerated concrete did not effect on the cracking strength of floating floor system.

This paper describes an experimental study of the effect of basalt wool on the acoustic isolation of the floating floor. Calculations and comparison of options flooring with use of acoustic insulation layer and without are shown. Analysis of the results of calculations are made.

In the present study, the vibration characteristics of floating floor systems and the discomfort in walking upon them have been studied in concrete slab structures through mock-up floors experiments. Seven types of floor systems, with panels of various sizes and supporting beams with different joist spacings, were constructed based on actual conditions. For the vibration measurement, an ISO rubber ball dropped from a height of 20 cm was used as an impact source to reproduce human walking. The vibration characteristics were evaluated by calculating the vibration acceleration values and the autocorrelation function parameters for the floor structures. Finally, a human walking experiment was conducted to investigate subjective responses to the vibration characteristics of floating floors. From the results, it was found that the vibration acceleration values and walking discomfort varied with the supporting conditions of the floors and that these were highly correlated with each other. It was also found that more than 75% of subjects accepted the floors when the vibration value of the floor in terms of vibration does value (VDV) is below 4.8 ms(-1.75). In addition, a practical regression of the VDV was obtained and design guidelines for floating floors were suggested.

The dynamic stiffness of a resilient material used under a floating floor is often used to predict the improvement of the impact sound pressure level, ΔL. It is also used to compare products. The measurement accuracy of this parameter is therefore essential. Unfortunately, the comparison between the predicted and the measured ΔL results shows quite high deviations which could be attributed, in part, to an incorrect estimation of the dynamic stiffness. It is now accepted by all European laboratories that the measurement procedure described in the standard ISO 9052-1 should be reviewed. This paper proposes a first step in the improvement of the measurement setup by taking into account the actual contribution of the dynamic stiffness of the air enclosed in the materials on the total dynamic stiffness. A new setup is proposed and some results are presented for products with different airflow resistivities.

In the present study, the effects of resilient isolators and viscoelastic damping materials on reducing heavyweight floor impact sounds from reinforced concrete structures were investigated using FEM simulations and in situ measurements. At first, the dynamic properties of the materials were measured using a beam transfer function method to include the properties in an FEM simulation. As a result, the damping materials provided a higher loss factor and dynamic elastic modulus than the resilient isolators. Subsequently, FEM simulations and in situ measurements were conducted to investigate the effects of the interlayers on the characteristics of floor impact sounds and vibrations. The results indicated that the impact vibration acceleration level and floor impact sounds at low frequencies were significantly decreased owing to the installation of damping materials, whereas the impact sound pressure levels at low frequencies were increased as a result of the use of resilient isolators.

Heavy-weight floor impact noise is directly related to the impact source and floor vibration property. Dynamic properties of the standard floating floor that is used in Korea was investigated using accelerance, acceleration energy spectral density(ESD), and structural modal test. In the standard floating floor, natural frequency was decreased by the finishing mortar mass and the damping ratio was increased. Bang-machine force spectrum acting on the concrete slab can be calculated using inverse system analysis. Impact force acting on concrete slab is changed by interaction of finishing mortar and resilient material. The amplitude of the bang-machine force spectrum was amplified in low frequency range(below 100 Hz), and over 100 Hz was decreased. Changed force spectrum influence to the response of structure vibration, so the heavy-weight floor impact noise level was changed.

Impact sound transmission loss is the ability of structure to absorb impact noise, which is formed by mechanical impulses (steps, falls). The impact noise is then spread to the elements connected to the floor structure, such as the ceiling and surrounding wall. Dynamic stiffness is one of the important parameters that affect the sound insulation of ceiling structures with floating floors. The article deals with the optimal design of acoustic insulation to the floor composition, combining different materials of various thicknesses with various characteristic properties.

At present, since global energy is becoming increasingly tight, it is imperative to develop green buildings and promote green technology. At the same time, it can also be integrated into the atmosphere of joint construction of green “Belt and Road” and the construction of Green Silk Road to make the green infrastructure build a harmonious and livable habitat for humanity. In terms of key technology of heat-insulation and sound insulation of the ultra-low energy-consumption green floating floor, analyzing and studying from status of research and development at home and abroad, sound insulation design of building, the design of the surface layer floating structure, technical characteristics of heat insulation and sound insulation of floating floor and moisturizing and sound insulation technology of floating floor, the advantages of ultra-low energy consumption green floating floor insulation are obtained finally.

Evaluation of floating floor at the design level imposes to take into account assumption of proper execution of this system, which means assertion of proper localization of dilation. Aim of this research is to analyse usefulness of Steady State Dynamics (SSD) simulation in the context of floating floor performance and execution errors such as global or local lack of circumferential dilatation. For this purpose, two-storey building with one room at each floor was simulated. Floating floor system was applied at structural ceiling between upper and lower floor. Excitation of system was done by application of pressure with given frequencies at central part of floor. Three types of systems were analysed: system without floating floor, system with properly executed floating floor and system with floating floor short-circuited to walls. Application of dynamic bridge was done gradually - at each wall - till whole floating floor was short-circuited. In the result of correlation between akin in-situ test compatible with standards, normative prediction of weighted impact sound reduction index and SSD simulations results was evaluated. Moreover, influence of dynamic short-circuit on floating floor system was analysed. Finally flanking vibration transition between upper and lower room with different systems was discussed. Principal conclusion of performed analysis is fact that SSD simulation results are sufficient to show vibration velocity spectrum nature of changes between systems with and without floating floor. What is more application of dynamic bridges at circumference of floating slab makes given system similar structural ceiling only system, which meets with akin in-situ test in matter of acoustic performance – similar nature of results of impact sound level with and without floating floor. Nevertheless, SSD simulation results are hardly agreeable with normative prediction and in-situ test of weighted impact sound reduction index.

This paper is concerned with the analysis of the dependence of low frequency impact sound transmission through floating floor systems on in situ matched resonances. The evidence for the floating floor matched resonances has been found previously considering laboratory and numerical tests for one concrete slab and floating floor with varying resilient layers. In the present paper, considering laboratory and field tests for concrete slabs and floating floors with different plan configurations, this evidence is strengthened as differences between laboratory and field measurements of the impact sound level were negligible for the bare concrete slab but not with the floating floor installed. These results were also confirmed numerically. The analysis indicates that the dependence of low frequency impact sound transmission through floating floor systems on in situ matched resonances should be considered in addition to the conventional single degree of freedom models in order to improve accuracy.

This work presents and analyses the experimental field results of the sound insulation from airborne and impact noise of the horizontal separating elements commonly used in the past, in which a uniform layer of sand was placed on top of the floor construction to serve as a base for the ceramic tiling. The results of the acoustic measurements show that when there is an intermediate layer of sand in the horizontal separating element between rooms, the sound insulation is greater than would be obtained with other construction systems with equal mass per unit area, where the floor is joined rigidly to the floor construction. The effect on the sound insulation between the rooms produced by this layer of sand placed between the floor construction and the tiling is that of a cushioning layer, and demonstrates that this type of structure acts as a floating floor., En este trabajo se exponen y se analizan los resultados experimentales in situ del aislamiento acústico a ruido aéreo y a ruido de impactos de elementos de separación horizontales, habituales hace años, en los que sobre el forjado se coloca una capa uniforme de arena que sirve de asiento al suelo cerámico. Los resultados de las mediciones acústicas muestran que, cuando en el elemento de separación horizontal entre los recintos hay una capa intermedia de arena, el aislamiento acústico es mejor que el que se obtendría con otros sistemas constructivos de igual masa por unidad de superficie, con el suelo unido rígidamente al forjado. El efecto de la capa de arena colocada entre el forjado y el suelo, en el aislamiento acústico entre los recintos, es el de una capa amortiguadora, que hace que este tipo de suelo pueda considerarse como flotante.

Timber buildings represent a robust alternative to traditional heavyweight constructions. They allow CO2 storage, high structure and performance reproducibility, fast assembly and final certification of every panel. Nowadays, acoustic insulation is one of the most requested performances on the part of inhabitants, but not always fulfilled. Since these kind of edifices are relatively new in the market, there are very few studies on acoustic properties, regarding on impact sound performances. In this paper, an in-depth analysis of impact noise on bare timber floors is presented, focusing on how impact sound reduction cannot be as efficient as in heavyweight constructions. Two new equations are proposed, modelling the impact sound pressure level of common bare timber structures and the influence of traditional floating floor systems is analysed.

The low frequency vibro-acoustic characteristics of a massive floating floor with continuous resilient layer are investigated with experimental measurements and numerical simulations using a hybrid FEA–SEA method. The results of the study indicate the occurrence of the in situ resonance of the floating floor system, which could be explained by the frequency matching between bending modes of the floating plate and the vibration isolator. The in situ frequency-matched resonance is considered to result in a sharp rise of the low frequency transmissibility of the vibration isolator and the impact sound. The difference between the in situ and the apparent natural frequency of the vibration isolator is assumed to be due to a reduced mass behavior of the floating floor in association with the base floor. It is inferred in the present work that contributing factors in the in situ frequency-matched resonance such as floating plate dimensions, elastic properties of the plate, and the location of an impact might affect the conventional regime of the single degree-of-freedom vibration isolation model for floating floors. The influence of floating plate dimensions on the occurrence of the in situ frequency-matched resonance might be considered as one of the factors affecting the differences in the low frequency impact sound of massive floating floors between laboratory and field measurements.

Floating floor coverings are widely applied in ship structures. With regard to the laminated composite shells made up of floating floor coverings and cabin deck and based on ANSYS system, a dynamics analysis on structures of three different kinds of floating floors is performed using FEM built upon laminated shell elements. The influence of rockwool board in terms of thickness, density and elastic modulus on structure dynamic characteristics is discussed. The performances of vibration control of three different floating floor structures are compared. The FEM performs well in analyzing and calculating the vibration control characteristics of structures, the results of which offer certain reference to the design and research on cabin deck covered with floating floor coverings.

The aim of the research was to evaluate an influence of floating floor construction specimen size on weighted reduction in impact sound pressure level ΔLW. The large size (area ≥ 10 m2) specimens should be used according to LST EN ISO 10140 series standards. The problem is that produce large specimens is expensive and time-consuming process. So more rapid and cheaper way is to use smaller size (area < 10 m2) specimens and perform measurements in real buildings with similar test conditions as in laboratory. For evaluation of the specimen size influence on reduction in impact sound pressure level ΔLW value sand/cement screed area discreetly was reduced from 13.4 m2 down to 0.5 m2. The test results showed strong dependence of reduction in weighted impact sound pressure level from specimen size. Relying on the test data it was derived relationship which could be applied for the correction of the determined ΔLW values when smaller size specimens (area < 10 m2) of floating floor constructions are used.DOI: http://dx.doi.org/10.5755/j01.ms.18.1.1350

Lightweight building systems in general suffer from poor sound insulation, especially in the low frequency region. Since no reliable mathematical models that can predict the impact sound pressure level exists, the lightweight building design is to a high extent based upon previous experience and upon measurements. A special difficulty is related to experimental measurements since the variation among identical units must not be neglected. A modern volume based lightweight wooden building concept has here been tested by numerous well controlled measurements, in laboratory as well as in more field like conditions. The volume construction technique offers new possibilities and challenges to improve sound insulation in light weight timber construction. The main purpose was to investigate how different constructional solutions in the floor, like plaster board, mineral wool, elastic glue, dividing board, floating floor etc., affect the sound insulation. Many of the tested modifications resulted in only marginally changed impact sound pressure level but parameters that substantially can improve the sound insulation were found in using elastic glue to mount the floor boards, to install extra board layers and to use floating floors.

In order to obtain reliable estimations of the impact sound insulation between rooms, it is necessary to know the acoustic performance of each element composing the floors. The contribution of the flanking transmissions, the attenuation of floating floors and the weighted normalized impact sound pressure level of the basic structure need to be determined in order to apply the simplified calculation method according to the EN ISO 12354-2 standard. With the aim of verifying the range of validity of the calculation method proposed by the EN ISO 12354-2 standard for typical basic beam floor structures, a research based on on-site measurements was conducted. This paper provides an analysis in terms of spectrum trend, predicted average weighted normalized impact sound pressure level and reduction of impact sound pressure level obtainable with a generic floating floor typology. The study can represent a starting point for a correct estimation of the impact sound insulation in new buildings and renovation plans.

In order to acquire a high quality of living environment, it is necessary to investigate the subjects of floor impact sound insulation. According to the characteristics of optimization design method and restricted optimization math model, the sound transmission between floor and adjacent room down through floating floor has been modeled in a finite-element method. Floating floor structure are studied to realize the design optimization when the room average sound pressures are selected as objective function. Predicted results show that when keep the whole thickness of floating floor fixed, result of dynamics optimization design can reduce room average sound pressure effectively. And when keep the whole thickness of floating floor unfixed, optimization results have been gotten on the total thickness of floor layer and resilient interlayer of the floating floor, and the average sound-pressure in room is lower than original one availably.

The Act for Promotion of Use of Wood in Public Buildings (Law No. 36 of 2010 of Japan) was enforced in 2010. The promotion of the use of wood can contribute to the prevention of global warming etc. A public building in a low layer is supposed to attempt making to timber construction by this act. Moreover it is expected that the building such as apartment houses comes to be made from timber construction. For effective use of the Japanese wood, CLT (Cross Laminated Timber), which had been used in Europe, was standardized by JAS (Japanese Agricultural Standard) as a building material in 2014. Among the objections and the troubles of buildings in Japan, the sound insulation performance is one of the most serious issues, especially floor impact sound insulation. We, however, have little knowledge about sound insulation of CLT building. Therefore we built a 3-story CLT model building for experiment and investigated the floor impact sound insulation and the flanking floor impact sound insulation. This paper presents the results of floor impact sound insulation and the surfaces vibration in a sound-receiving room. The results showed the influences of damping material, ceiling and floating on the floor impact sound insulation, and the floating floor showed possible improvements in the heavy-weight and the light-weight floor impact sound insulation of CLT building. The vibration velocity level of the ceiling was the largest. However, it is necessary to decrease the vibration velocity level of the sound-receiving room's wall for improvement of the heavy-weight floor impact sound insulation by using damping material.

Field measurements of floor impact sounds at low frequencies give poor repeatability due to spatial sampling problems. In this study, the spatial distribution of heavy-weight impact sound pressure levels was investigated by field measurements using heavy/soft impact sources, which have been specified as a standard heavy-weight impact source in 140-11. The results of the present study showed that the vertical and horizontal distribution of measured sound pressure levels showed a significant room mode effect at low frequencies. Among the existing standards for measurement of a heavy-weight impact sound, KS F 2810-2 and JIS A 1440-2 provide an appropriate estimation of the room average sound pressure level for bare slab and floating floor, with respect to a low bias error and 95% confidence interval. The guideline for measurement of a heavy-weight impact source was recently proposed in order to complement the limitations of KS F 2810-2 and JIS A 1440-2, and it has been shown that the guideline appropriately performed in the test building and in living rooms of tested apartment buildings.

By establishing finite element model of load floor based on the field data, this work evaluated vibration of load floor after isolation measures were taken through effective value of acceleration of vibration. And it demonstrated that the floating floor slab was very useful for vibration isolation for load floor whose buildings have been completed. What’s more, the thesis also provided reference standards for further studies on vibration isolation for load floor caused by large-scale rotating machinery on the floor.

In this paper, a new design concept of a lightweight floating ceiling with a special arrangement of stiffener beams and isolators is proposed to enhance vibration isolation performance. The key design parameters of resonant frequency of bending and mode shape factor on vibration transmission are determined with some simple formulae. Structural vibrations and noise radiation are evaluated with finite element models (FEM) for various designs. The optimum ceiling designs are applied in a studio, and field measurements with reliable frequency range of 30–400 Hz are conducted to confirm the theoretical results. The analyses ascertain that four design features ensure the optimum vibration isolation performance: the stiffener beams must be installed at the nodal line of fundamental bending resonance of the plate; smaller panels should be applied instead of a large panel covering the whole area of the ceiling, and joints should be free; the isolators should be placed at the nodal point of the bending mode of the plate; and the fundamental bending resonance frequency must not match the modal critical frequency. The proposed stiffened wooden panel design achieved a noise and vibration reduction of 20 dB in the frequency range of 40–100 Hz, and was better than the performance of a concrete floating floor.

The floor system of apartments must have a certain level of floor impact sound performance (light-weight impact sound is 58 dB or less, heavy-weight impact sound is 50 dB or less), and comply with the building energy code to prevent energy loss in residential buildings in Korea. In this study, expanded polystyrene (EPS), expanded polypropylene (EPP), ethylene-vinyl acetate copolymer (EVA), polyethylene (PE) and urethane foam, which are widely used in Korea as resilient materials for floating floor system of apartments, were measured. Their thermal conductivity and apparent density were measured to analyze their thermal properties and their relation was analyzed by material. In case of resilient materials made of EPS and EPP, thermal conductivity tended to decrease as apparent density increased, whereas in case of resilient materials made of EVA and PE, as apparent density increased, thermal conductivity tended to increase as well.

A numerical model was developed for a floating floor with an inserted viscoelastic layer to predict the structure-borne noise (SBN) in ship cabins. In cabins, high-density mineral wool is usually used as an impact-absorbing material. The theoretical model consisted of multipanel structures lined with high-density mineral wool. The predicted results for SBN when a floating floor with an inserted viscoelastic layer is used were compared with the measurements done on a cabin mock-up. Various floating floors with inserted viscoelastic layer structures were studied, and the effects of variations in the thickness, density, and fiber direction of the high-density mineral wool were investigated. Comparisons of the predicted results and the experimental results showed that the developed model could be an effective tool for predicting SBN in ship cabins.

In this paper, noise and vibration reduction for floating-floored ship cabin is studied. A mock-up is built by using 6 mm steel plate, and two identical cabins are made for simulation of ship cabins. When a speaker is used as a sound and vibration sources, it is shown that floating floor is more effective in isolating sound than bare deck by 2-5 dB. It is also shown that structure-borne noise of the bare deck is greater than that of floating-floored deck by 3-10 dB. For tapping machine excitation, it is found that the effect of floating floor in airborne noise and structure-borne noise reduction reaches up to 40-50 dB for high frequency ranges.

The paper presents a procedure developed for designing new floating floors for marine applications. The procedure aims at the improvement of the capability of a new floating floor to isolate structure borne noise. After an introduction to the theoretical background on which this procedure is built, the authors present the results obtained applying the developed procedure to a case study. The procedure includes numerical Finite Element simulations and experimental tests. The simulations aim at the optimization of the resilient material used to decouple the upper floor from the structures. The optimized configurations are then built and tested in laboratory. These tests allow the researchers to identify the floating floor resonances and to evaluate their effect on the Transmission Loss levels. The results of the research activity show the effectiveness of the developed procedure and highlight the importance of the experimental tests to validate the outcomes of the simulations.

In this paper, a new design concept of an isolated honeycomb floor with a special arrangement of isolators is proposed to improve the vibration isolation performance of conventional lightweight cement floor panels in the frequency range of 120–600 Hz. The symmetric bending resonance frequencies and mode shapes of a honeycomb floor panel were identified by a shaker test. The effects on vibration isolation of isolator position and acoustic insulation were then investigated using experimental modal analysis. The analysis suggests that four design features ensure the optimum vibration isolation performance of a square floating honeycomb floor: the floor panel should be small, stiff, and lightweight; the isolators must be placed at the nodal points of the symmetric bending modes of the floor panel; the vibration must be transmitted via the center point of the floor panel; and acoustic insulation material should be installed inside the cavity. The proposed floating floor design achieved a vibration reduction of 20–30 dB in the frequency range of 120–600 Hz. In addition, the proposed floor was found to have a 20 dB lower vibration level at the first bending resonance frequency than the conventional design with isolators that are placed at the edges.

An extensive measurement survey of timber floor constructions has been carried out by the acoustics laboratory of the Belgian Building Research Institute [1]. The basis of this study was the airborne and structure-borne sound insulation measured on a bare joist floor with OSB (Oriented Strand Board) sub floor. By adding different floor toppings and gypsum board ceilings to the basic floor construction, gradual improvements were recorded. A large number of floors are evaluated in the laboratory and formed a database for parametric studies. Improvements due to cavity absorption, floating floors and suspended ceilings were quantified and ranked by effectiveness. Measurement results revealed remarkable differences between floating floor systems. In addition, sound insulation measurements have been performed on joist floors with concrete toppings. The so-called mixed concrete-timber floors provide a higher mechanical resistance. The effect of the bonding and topping type on the airborne and structure borne sound insulation has been examined in the laboratory. The results of this additional research are briefly compared to traditional floor systems and compared with the (future) Belgian standard values. An overall evaluation of the acoustic relevance of timber floor partitions in and between dwellings is also made.

This paper looks at the performance that can be achieved using timber platform floors on concrete floor bases in order to design a platform floor that could provide at least 29dB Δ Lw (both loaded and unloaded) for use in floor constructions described in Approved Document E (2003 Edition). Reconstituted open cell foams were identified as resilient materials that could provide suitable static and dynamic stiffness under lightweight timber floating floors. Using two layers of reconstituted foam a platform floor comprising 22m tongue and grooved chipboard achieved 29dB Δ Lw when loaded, and 30dB Δ Lw unloaded. Indicative tests on double platform floating floors indicated that they may be beneficial in floor designs where negative values of Δ L can not be tolerated due to critical impact sound insulation and structural stability requirements. A double floating floor could use dynamically stiffer resilient materials than would be needed in a single floating floor and still provide the required impact sound insulation and structural stability.

In this Paper, reduction of noise and vibration in ship cabins by using floating floor is studied. Two theoretical models are presented and predicted insertion losses of floating floor are compared to experimental results, where measurements have been done in mock-up built for simulating typical ship cabin structures. In ships, mineral wool is usually used as the impact absorbing materials. The first model (M-S-Plate Model) is that upper plate and mineral wool are assumed as a one-dimensional mass-spring system, which is in turn attached to the simply supported elastic floor. The second model (Wave-Plate Model) is that mineral wool is assumed as an elastic medium for wave propagation. The comparisons show that M-S-Plate model is in good agreement with experimental results when density of mineral wool is 140K, and fiber direction is horizontal. For higher density and vertical fiber direction, Wave-Plate model shows good agreements with measurements. It is found that including the elastic behavior of the floor is essential in improving accuracy of the prediction for low frequency ranges below .

In this paper, floor impact noise reduction in cruise ship cabin is studied. A mock-up is built by using 6t steel plate, and two identical cabins are made where 25t panel is used to construct wall and ceiling inside the steel structure. Various floating floor systems are tested for which normalized impact noise is measured according to ISO 140-7. In addition, floor SBN (Structure-borne Noise) and floor damping are measured to study the effect of floating floor structure. It is shown that VL(Visco-elastic Layer) is more effective when hard plates are added above the VL.

Impact sounds, such as those created by footsteps, the dropping of an object or the moving of furniture, can be a source of great annoyance in residential buildings. The character and level of impact noise generated depends on the object striking the floor, on the basic structure of the floor, and on the floor covering. This study base on the evaluate of isolation performance of impact sound according to the impact noise reduction methods. Reduction methods consist of four ways. First way is increase thickness of bare floor and other ways are using the soft coverings on the floor and ceiling assembles. Last way is make floating floor with shock absorbing materials.

The acoustic behaviour of two building systems, a traditional concrete structure and an innovative one involving expanded polystyrene (EPS) elements have been compared using field measurements. The results indicate that the airborne sound insulation is very similar for both construction methods, whereas impact sound insulation is better for the innovative system. The improvement obtained by introducing polyethylene foams in floating floor constructions has also been investigated for the EPS system using field measurements. Also, the impact sound insulation improvement obtained with two different polyethylene foams has also been analysed by performing laboratory experiments. Whilst both materials are adequate for this application, results indicate that the non cross-linked foam has a better performance.

Due to favorable sound isolation to the impact sound transmission, People are prone to adopt floating floor as insulation structure. Of the researches on impact sound insulation through a floating floor, the theoretical study is much less than the experiment analysis. For the purpose to determine sound insulation and the dominate sound transmission path through a floating floor, the Statistical Energy Analysis(SEA) is employed to set up a theoretical model for predicting sound transmission across two floor plates connected by a resilient interlayer, and there are two main paths: the stud path and the cavity path. It reveals that the resilient interlayer plays a key role in impact sound insulation of a floating floor, and there exists a good agreement between predicted and measured sound pressure level (SPL) in the rooms below the floors.

Acoustic and thermal performances of floating floor and/or radiant floor can be improved by using ceramic tiles with tailored porosity and microstructure. Porcelain stonewares are still the most widespread typology of tiles, due to their high physical and mechanical performances coming from a very low level of open porosity and water absorption (≤0.5 wt%). However their closed porosity values, usually neglected, can be significantly different from one product to another. As a consequence, the properties directly dependent on the total porosity, such as thermal and acoustic ones, may be strongly diverse among commercial tiles. Several commercial porcelain stoneware tiles having different composition, microstructure and porosity, were selected for the present work. These tiles, alone or coupled with different types of resilient underlayer materials (glass fibre, cork and rubber), were studied on the basis of dynamic stiffness. Their acoustic and thermal properties were investigated in terms of thermal conductivity and walking noise reduction.

In the floating floor system the performance of resilient layers, in terms of impact sound pressure level reduction, is of paramount importance. In the present study in order to evaluate the time-depending performances, a comprehensive characterization of twenty different layers was carried out, evaluating dynamic stiffness, compressibility and compressive creep. The aim of this work was to find out a possible correlation among these parameters and the effect of service time on mechanical and acoustical properties. Results indicated that a general rule couldn’t be defined. Furthermore, the presence of a coating, as well as different density and/or contact shape, has proved to influence the final acoustical performances.

In this paper a theoretical model to predict bending wave transmission through parallel plates connected by a resilient line is presented. The model is based on the interaction of semi-infinite plates intersecting along an infinite boundary. A full model is developed together with some approximations for the more common cases. The results of the model are then used in a statistical energy analysis (SEA) framework to predict transmission through a chipboard floating floor attached to battens which in turn are supported on a concrete floor. Acoustic transmission through the cavities is also considered. The results show that transmission through the battens is the most important path when there is no resilient layer but that this path is insignificant if any resilient layer is present. A comparison between measured and predicted results gave generally good agreement except at high frequencies when a resilient layer was present.

Il progettista navale deve far fronte a richieste sempre più esigenti in termini di comfort di bordo, soprattutto per imbarcazioni da crociera e yacht di alta qualità. Le tecniche per la valutazione dei livelli di comfort offerti a bordo sono sempre più evolute ma si scontrano con strette tempistiche progettuali e onerosità di calcolo. Per questo motivo la progettazione dei sistemi di isolazione del rumore e delle vibrazioni si basa ancor oggi su approcci numerico-sperimentali. In questo ambito, al fine di promuovere l’approccio razionale al progetto e all’ottimizzazione degli isolamenti da ponte, viene qui proposta una procedura che coniuga rigore scientifico e praticità nella selezione dei sistemi di isolazione ad alte performances. In quanto segue, dopo una breve presentazione della problematica del comfort vibro-acustico, viene illustrata la pratica odierna nella caratterizzazione vibro-acustica dei floating floors e infine viene introdotta la procedura proposta portando un esempio applicativo.

The final destination for waste polymers EVA (Ethylene Vinyl Acetate) discarded by footwear industries has been recognized as a increasing problem of impact on the environment. However, studies have show that these residues have characteristics suitable for recycling purposes transforming them into lightweight aggregates, which may provide benefits to the environment for example, their use to attenuate effects of noise impacts problems on the floors, which are very common in multi floor buildings. This research aims to evaluate the acoustic performance of cement boards, consisting of waste aggregates EVA (EVA boards), applied as a resilient material in the composition of floating floor. In this study three types of EVA boards were developed with different thickness and geometries, one of which has whole flat surface (EVA_ar0) and the other with a low relief surfaces (EVA_ar1 and EVA_ar2,5), to yield a layer of air between these boards and the slab. The plates were evaluated for the ability to soundproofing, following the guidelines of ISO 140-7:1998 and ISO 717-2:2013, seeking to compare their performance with some materials available for use in floating floors, for example, polyethylene acoustic blanket and rock wool. The assessment of the level of sound insulation to mitigate the noise impact was performed in a Testing Laboratory of Materials and Structures, Federal University of Paraiba, simulating a situation between two adjacent floors. Based on the results it can be stated that the boards EVA, according to their performance achieved, has the potential to rank as an alternative material used for mitigation of impact noise between floors of multi floor buildings. The floating floor system composed with the board EVA_ar2 , 5 (with air 2.5 cm layer ) had global number (L'nT,w) equal to 64 dB, framed with better intermediate level of performance (I) the that the performance of other systems with boards EVA_ar0 (without air layer) and EVA_ar1 (with air 1 cm layer) obtained global number 67 and 66 dB respectively classifying performance with minimal (M), according to NBR 15.575-3:2013. Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES A destinação final para os resíduos de polímeros de EVA (Etileno Acetato de Vinila) descartados pelas indústrias calçadistas tem sido reconhecida como um problema crescente de impacto no meio ambiente. Contudo, estudos têm comprovado que esses resíduos possuem características adequadas para propósitos de reciclagem transformando-os em agregados leves, que podem trazer benefícios ao ambiente construído, como por exemplo, o seu aproveitamento visando atenuação de problemas de ruídos de impactos nos pisos, que são muito comuns nas edificações multipavimentos. Portanto, essa pesquisa tem como objetivo avaliar o desempenho acústico de placas cimentícias, executadas com agregados de resíduos de EVA (placas de EVA), aplicadas como material resiliente na composição de sistemas de piso flutuante. Nesse estudo foram desenvolvidas três placas de EVA com espessura e geometrias diferentes, sendo uma delas com todas as superfícies planas (EVA_ar0) e outras duas com uma das superfícies com baixo relevo (EVA_ar1 e EVA_ar2,5), de modo a resultar uma camada de ar entre tais placas e a laje. As placas foram avaliadas quanto a capacidade de isolamento acústico, seguindo as diretrizes das normas ISO 140-7:1998 e ISO 717-2:2013, procurando comparar seu desempenho com alguns materiais disponíveis no mercado para uso em pisos flutuantes, como por exemplo, manta acústica de polietileno e lã de rocha. A avaliação do nível de isolamento acústico para atenuar os ruídos de impacto foi realizada em protótipo no Laboratório de Ensaio de Materiais e Estruturas da Universidade Federal da Paraíba, simulando uma situação entre dois pavimentos sobrepostos. Com base nos resultados pode-se afirmar que as placas de EVA, de acordo com seu desempenho alcançado, tem potencial para se classificar como um material alternativo utilizado para atenuação de ruído de impacto entre os pisos de edificações multi pavimento. O sistema de piso flutuante composto com a placa de EVA_ar2,5 (com camada de ar de 2,5 cm) obteve número global (L´nT,w) igual a 64 dB, enquadrado com nível de desempenho intermediário (I) melhor do que os desempenhos dos outros sistemas com as placas do EVA_ar0 (sem camada de ar) e EVA_ar1 (com camada de ar de 1 cm) obtiveram número globais 67 e 66 dB respectivamente se classificando com desempenho mínimo (M), segundo a NBR 15.575-3:2013.

The most relevant parameter for assessing the acoustical properties of insulation layers for floating floor applications is the dynamic stiffness. Besides the surface mass of the floor plate the dynamic stiffness influences the reduction in impact sound pressure level of a floating floor. According to the formerly German measurement standard DIN 52214 the dynamic stiffness of impact sound insulation materials had to be measured after applying a short-term pre-load of 50 kNm−2. This pre-load does not reflect the conditions in the field and has been withdrawn in EN 29052-I. By comparison of measured field data for floor constructions with estimated data based on measurements with and without pre-load it is shown, that the new measurement procedure in connection with a more detailed estimation of the building element properties leads to a more accurate prediction of impact sound insulation in dwellings.

Floating lining system has been employed to reduce noise level in cabins. However, the noise reduction level is approximately 10dB (A) and it is not satisfactory. Therefore, more effective system is desired to be realized. This paper presents the reason why the conventional systems have poor effects and shows the techniques to improve the effects. The present system is consist of a box made of four lining walls and a ceiling set on a floating floor, and the box has no connecting points to the steel structure except a few rubber pieces. Experiments with the presented system were carried out by using a scale model. Employing the new system, the vibration level on the lining could be the same level as the floating floor and the vibration level of the lining is more than 10dB lower than the conventional system in wide frequency ranges.

Crossfit facilities in dense, multi-use facilities are growing in numbers every day. Even minimally sensitive receivers can be very significantly impacted by Crossfit activities. Consequently, vibration and vibration induced noise in structures as a result of heavy weight drops are a never ending issue. This paper compares data recorded from heavy weight drops in an ASTM E492 floor/ceiling testing suite. The resultant sound pressure level in the receiving room and vibration levels in the structure are measured. Several different standard and high performance resilient sports floorings are compared. These sports floors are tested on single concrete slabs as well as various floating slabs. The floating slabs include continuous rubber underlayments, discrete rubber isolators and spring jack-up floating floors. In addition, laboratory impact and airborne isolation performance results of a spring jack-up floating floor are reported.