JPH0378900B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a floor member that alleviates vibrations caused by impact on a building floor and also prevents impact sound from propagating downward.

BACKGROUND OF THE INVENTION In recent years, neighborhood noise, particularly floor impact noise caused by children jumping in apartment complexes and detached houses, has become a major problem.

Conventional techniques for preventing floor impact noise include, for example, Utility Model Application Publication No. 54-11964, Japanese Patent Application Publication No. 58-53978, and Japanese Patent Application Publication No. 59-Sho 59-
As seen in 98121 or Japanese Patent Publication No. 53-37644, most of them depend on the vibration-proofing effect of the material.
For this reason, it has been extremely difficult to significantly prevent or improve the generation of medium to low frequency sounds, particularly low frequency sounds, caused by floor vibrations.

Problems to be Solved by the Invention As a result of various studies to solve these problems, the inventor of the present invention found that, in general, when trying to improve one of the vibration damping properties and vibration damping properties of a viscoelastic material, the other becomes worse. However, no matter how good the material is, if the vibration-proofing properties are poor, impact noise will not be improved. We have discovered that it is possible to significantly improve floor impact noise by imparting even greater vibration damping properties to a member while maintaining sufficient vibration damping properties, leading to the present invention.

Means for Solving the Problems The gist of the present invention is to form a filler made of a fibrous sound absorbing material using a viscoelastic material so that the diameter of the maximum circle enclosed is 5 to 150 cm and the frame width is 2 to 50 mm. A frame body having a loss coefficient of 0.2 or more is filled in the frame body, and a surface material made of an elastic polymer substance is laminated on both the upper and lower surfaces of the frame body. In the formula K=1/ _o 〓 ⁱ⁼¹ d _i /E _i formed between ratio and thickness, if the value of K is 2×10 ⁹ N/m ³ or less and the interlayer member between floorboards A floor impact sound prevention member characterized in that it is used.

(In the above formula, E is the Young's modulus of the filler and surface material, d is the thickness of the filler and surface material, n is the filler,
Indicates the number of constituent materials of the surface material. In other words, the present invention aims to prevent and attenuate floor impact noise by providing the frame with excellent vibration damping properties and giving due consideration to the vibration damping properties of the surface material and filling material. . The present invention will be explained below.

As the filler in the present invention, fibrous materials that generally have sound absorbing properties, such as glass wool and rock wool, are used singly or in a layered manner. The frame body into which the above-mentioned filling material is inserted is made of a polymer material with a loss coefficient of 0.2 or more, especially a viscoelastic material such as synthetic resin or rubber, or mixed with fibers or fine powder to improve vibration damping properties. Composite materials etc. are used.
The size of the frame is such that the diameter of the maximum circle included in the outer periphery of the frame is 5 to 150 cm, and the thickness of the outer and inner edges of the frame, that is, the frame width, is 2 to 50 mm.

If the loss coefficient is less than 0.2, the vibration damping effect of the floor member according to the present invention will be poor, and the purpose of the viscoelastic material will not be achieved. Preferably it is 1 or more. Further, the size of the frame is determined in consideration of general practical performance as a flooring material, such as workability, durability, economic efficiency, etc., and also taking into account improvement in vibration damping properties, which is the objective of the present application. From the point of view of improving vibration damping performance, it is better to install many small frames, but on the other hand, it is less workable and economical.
Furthermore, the vibration damping properties may also be inferior, which is undesirable.
From these, if the diameter of the maximum circle included in the outer periphery of the frame is 2 cm or less, the number of installations will be too large, resulting in poor construction efficiency and economic efficiency, and furthermore, depending on the rigidity of the frame, vibration-proofing performance may be affected. On the other hand, if it is 150 cm or more, the difficulty of construction increases due to the increased weight, and the economical efficiency is also poor, both of which are unfavorable.

In addition, the frame width between the outer edge and the inner edge of the frame, that is, the thickness of the frame, is set to 2 to 50 mm in order to ensure the durability of the main floor member, add vibration damping properties, and maintain vibration damping properties. It does not necessarily have to be formed with a constant width.
If it is less than 2 mm, overall sagging tends to occur and the damping effect will not be exhibited. If it is 50mm or more, the anti-vibration properties tend to be impaired and it becomes extremely uneconomical. That is, when a large impact force is applied to this member, the entire floor member is compressed, and this compression causes the frame to bend and deform to a large extent laterally. During this deformation, vibrations propagated to the frame are converted into thermal energy, thus absorbing impact force. For this reason, if the frame width is 50 mm or more, combined with the material having a loss coefficient of 0.2 or more, the frame becomes difficult to deform, and a sufficient vibration damping effect will not be exhibited. Furthermore, as the area and volume within the frame become smaller, it becomes difficult to ensure sufficient vibration isolation, and as a result, the vibration isolation performance that prevents vibrations due to elasticity is likely to be impaired.

Next, as the surface material laminated on both the upper and lower surfaces of the frame, a sheet-like material made of elastic synthetic resin or rubber is used in order to maintain sufficient vibration-proofing properties. Note that the surface material may be a sheet consisting of only one layer, or may be a sheet consisting of multiple layers made of different materials.

The thickness of the surface material is preferably about 1 mm to 10 mm. If it is less than 1 mm, the strength will be poor and a sufficient vibration-damping effect cannot be exhibited, while if it is more than 10 mm, it will be less economical and may hinder the deformation of the frame, which will likely impair vibration-damping performance, both of which are undesirable. Further, the surface material is laminated on the upper and lower surfaces of the frame to seal the filler, and has an impact noise prevention effect utilizing the flow characteristics of the sealed air, which will be described later.

Lamination on the frame is performed by known means such as adhesion or fusion. Further, the frame preferably has a rectangular or square shape, but may also have a circular, trapezoidal, rhomboid, triangular, or other polygonal shape.

As shown in FIG. 1, the floor impact noise prevention member according to the present invention described above includes, for example, a rectangular frame 1 with a filler 2 filled in the frame and a surface material 3 on both the upper and lower surfaces of the frame. Composed of layers.

In this member, it is preferable that the surface material and filler have high vibration damping properties as well as the frame, but as mentioned above, when trying to impart high vibration damping properties, the elastic modulus of the material or the (apparent) ) will increase the spring constant, and the anti-vibration effect will be impaired.
In order to maintain vibration isolation and damping, the above-mentioned surface material and filler must collectively have elasticity above a certain value. Therefore, the thickness of the surface material and filling material
d ₁ , d ₂ , d ₃ ...d _o (n is the number of surface materials and fillers)
and the Young's modulus of the surface material and filler E ₁ , E ₂ , E ₃ ...E _o The formula is formed between K=1/ _o 〓 ⁱ⁼¹ d _i /E _i , and the value of K is 2× Must be less than ¹⁰⁹ N/ ^m3 . In other words, if K≦2×10 ⁹ N/m ³ , the surface material and the filler can sufficiently secure vibration damping properties, and therefore, the floor member according to the present invention can suppress vibrations without impairing the vibration damping effect. It can improve vibration properties.

The Young's modulus of the filler used in the above equation is:
This is a measurement value when normal air circulation is ensured. Furthermore, the same applies when different materials are mixed as fillers or when molded using adhesive.
The Young's modulus measured in a state equivalent to the state in which the mixture and molded product are used is used. In addition,
Young's modulus is determined by the slope of the straight line portion of the stress-strain diagram.

Furthermore, since the floor member according to the present invention has a structure in which the filler and air are sealed within the frame, this air hits the wall of the frame as a uniform fluid with impact within the closed frame, causing the frame to This causes large bending deformation, which is one of the reasons for improving vibration damping performance. Additionally, the upper and lower surface materials are pressed tightly against the upper and lower floorboards to suppress board vibration. However, it is difficult to satisfy the K value of the above formula using air alone, and it is necessary to use the above-mentioned filler having a high porosity.

Function There are no particular restrictions on how to use the floor impact noise prevention member according to the present invention as explained above, but depending on the load capacity of the main floor member, it may be necessary to place the intermediate part between the floating floor and the foundation floor as a cushioning material. It only needs to be installed so that it makes sufficient contact with both the upper and lower floors, and the area occupation rate on the floor is 10.
% to 80%, considering economic efficiency. A particularly preferred method of use is to use or install a large number of floor members with a high K in the above formula for the peripheral areas of the construction floor surface, while using members with a relatively low K near the center. The apparent spring constant of the floating floor may be changed between the center area, which is susceptible to impact, and the peripheral area, where heavy items such as furniture are placed, by using a floating floor or reducing the number of floating floors installed.

Effects of the Invention When the floor impact sound prevention member according to the present invention formed as described above is installed under the floating floor (or placed floor) layer as shown in FIG. This significantly impedes downward impact transmission, greatly attenuates vibrations in various parts of the floorboard, and significantly reduces floor impact noise. It is particularly effective for weight impact sources that are difficult to improve, such as the low frequency range from several tens of Hz to approximately 200 Hz caused by children jumping. Furthermore, since the present invention is a dry method and has a structure in which the filler is sealed, workability is improved, the adverse effect on livability due to flying objects (for example, glass fibers) is prevented, and no dew condensation occurs. Furthermore, since the frame part shares the load, there is very little ``settling'' of the filler material, and there is flexibility in the arrangement of main floor members, making it possible to carry out construction that takes into account the target value for improving floor impact noise and economic efficiency. It is possible.

Comparative Example 1 As shown in Figure 2, a two-story wooden house constructed using conventional construction methods consisting of large beams, joists, and plywood base (the second floor is
Compliant with each JIS A 1418 "Method for measuring floor impact sound levels at building sites" for the foundation floor of a tatami room (consisting of tatami mats), where particle board with a thickness of 40 mm is laid as a floor throughout the room. Tires (heavy impact) and tapping machines (light impact)
The floor impact sound level in the room immediately below (first floor) was measured by sequentially excitation. The results are shown in FIG. 4 (under tire vibration) and FIG. 5 (under tapping machine vibration). As shown in the figure, in Comparative Example 1,
The floor impact noise of wooden houses is loud, and the sound pressure level is particularly high in the low frequency range of around 50Hz and the midrange of around 250Hz to 1kHz. Note that particle boards of this thickness are rarely used in typical wooden houses, and the floor impact noise value is even worse.

Examples 1 and 2 As shown in FIG. 2, the following floor impact noise prevention member according to the present invention was placed between the foundation floor used in Comparative Example 1 and the floor.

The frame is made of norbornene rubber (manufactured by CDF, product name: Norsolex), and is square with a side length of 20 cm (therefore, the diameter of the largest circle enclosed is also 20 cm).
cm), the frame width is 8 mm and the height is 12 mm, and the frame is filled with high-density glass wool (manufactured by Nippon Glass Wool Co., Ltd., density 96 kg/m ³ , thickness 12 mm), and frames are placed on both the upper and lower sides of the frame. 2 mm thick sheets of the same norbornene rubber used for the body were laminated together by fusion bonding.

Ninety-one of these main floor members were arranged and constructed as shown in Figure 3A.

In Example 1, the loss coefficient η of the frame is 0.23.
(Measure the rebound modulus R by the Liupke method, and use the formula η
= -1/πlnR (the same applies hereafter), and the floor impact sound prevention member with a K value of 2.2 × 10 ⁸ N/m ³ due to the surface material and filler is used as Example 2.
Norbornene-based rubber with different amounts of filler was used to form the frame body with a loss coefficient η = approximately 1.5, and floor impact sound prevention members with a K value of 5.3 × 10 ⁸ N/m ³ were used. Similarly to Comparative Example 1, the floor impact sound levels of tires and tapping machine vibrations were measured. The results are shown in FIGS. 4 and 5. As shown in the figure, both Examples 1 and 2 are improved over the entire frequency range compared to Comparative Example 1.
Around 5 dB, compared to Comparative Example 1 in the low frequency range for Example 2 with high damping performance.
It has also been improved by 10dB.

Comparative Examples 2, 3, 4 As Comparative Example 2, a block of 5 cm (vertical) x 5 cm (horizontal) x 0.8 cm (height) was made of the norbornene rubber (loss coefficient 0.23) used for the frame part in Example 1. 91 pieces were arranged and constructed in the same manner as in Example 1.

The K value of the rubber block used was 3.1×
It was ¹⁰⁹ N/ ^m3 .

As Comparative Example 3, construction was carried out in exactly the same manner as in Example 1, except that the thickness of the frame width of the frame used in Example 1 was changed to 1.5 mm.

As Comparative Example 4, only the glass wool used in Example 1 was placed over the entire floor between the foundation floor and the installation floor.

For these Comparative Examples 2, 3, and 4, floor impact sound measurements were performed in the same manner as in Comparative Example 1. The results are shown in FIG. Note that the measurements were performed only on tire vibration, which is a weight impact.

As shown in the figure, although both showed a slight reduction effect in the high frequency range of 1 kHz or more, it was extremely insufficient in the important low and middle frequency ranges. As a result, even if it has vibration damping performance, if it does not have elasticity above a certain value, that is, if it has poor vibration damping effect,
It can be seen that the impact noise as a whole is not improved (Comparative Example 2).

Furthermore, it can be seen from Comparative Example 3 that if the frame width of the frame body is too small, sufficient vibration damping performance cannot be exhibited.

In addition, it can be seen from Comparative Example 4 that glass wool alone hardly contributes to the improvement of impact noise, regardless of its heat insulation properties.

Examples 3 and 4 Furthermore, as shown in Figure 3B, the number of main floor members used in Examples 1 and 2 was reduced by almost half to 51, and the same measurements as in Comparative Example 1 were conducted. The floor member used in Example 3 was the same as that used in Example 1, and the floor member used in Example 4 was the same as that used in Example 2. The measurement results during tire vibration are shown in Figure 6. The results showed that in Example 3 there was almost no difference compared to Example 1, and in Example 4 there was a slight tendency for deterioration compared to Example 2. The superiority of the performance in preventing impact noise is not impaired, and the changes in each performance are close to those predicted theoretically from the contribution of the vibration damping or vibration isolation properties of this member.

Therefore, it can be seen that the number of used members (occupied area ratio) has a degree of freedom that can be changed according to improvement goals and economical efficiency.

[Brief explanation of drawings]

1A is a plan view of a floor impact noise prevention member according to the present invention, FIG. 1B is a sectional view, FIG. 2 is a sectional view of a floor portion of a two-story building structure, and FIGS. 4 is a plan view showing the arrangement of the main floor member, FIG. 4 is a drawing showing the impact sound levels of Examples 1 and 2, and Comparative Example 1 when tire vibration is applied, and FIG. A drawing showing each impact sound level under vibration.
Figure 6 shows Examples 3 and 4, Figure 7 shows Comparative Example 2,
3 is a drawing showing the impact sound level under tire vibration in No. 3 and No. 4, respectively. 1... Square frame body, 2... Filler material, 3... Surface material.

Claims (1)

[Claims] 1. A filler made of a fibrous sound-absorbing material is formed using a viscoelastic material with a maximum enclosed circle diameter of 5 to 150 cm and a frame width thickness of 2 to 50 mm, and the loss coefficient is 0.2.
The above-mentioned frame is filled in the frame, and a surface material made of an elastic polymer substance is laminated on both the upper and lower surfaces of the frame, and the Young's modulus and thickness of the filler and surface material are different from each other. In the formula K=1/ _o 〓 ⁱ⁼¹ d _i /E _i , the value of K is 2×10 ⁹ N/m ³ or less, and it is used for an interlayer member between floorboards. Floor impact noise prevention member. (In the above formula, E is the Young's modulus of the filler and surface material, d is the thickness of the filler and surface material, n is the filler,
Indicates the number of constituent materials of the surface material. )