ES2395660A1 - Mortar for covering structural elements, with high acoustic performance levels - Google Patents

Abstract

The incorporation of a covering mortar based on cement and granulated coke with particle diameters between 1 and 6 mm, into structural elements such as a brickwork extrados, gives a dual effect of enhanced acoustic insulation. This effect is due to the increase in the mass by the spraying of the mortar and to acoustic absorption as a consequence of the porous network of the material applied. The acoustic performance levels achieved exceed those of the same configuration as a double wall but with the incorporation of mineral wool into the cavity, and also that of conventional cement and sand mortar. Furthermore, covering mortars are in any event necessary to guarantee the external leaktightness of brickwork. Moreover, the fact that the coke mortar is thinner (15 mm) than mineral wool mortar (50-80 mm) reduces the total thickness of the elevation and thereby increases the useful surface area of the built structure.

Description

Coating mortar of construction elements with high acoustic performance

SECTOR OF THE TECHNIQUE

The present invention is framed in the construction sector, and more specifically in the acoustic products industry, which also forced by a foreseeable greater demand must have alternative products that can efficiently replace mineral wool, as may be the case of mortars based on porous cokes.

STATE OF THE TECHNIQUE

In order to obtain a sound wave absorber product, a material with a large open porosity is required, with open porosity being understood as a solid skeleton traversed by pores communicated with each other and with the outside, since sound damping occurs by the tortuous route through the porous space, with the consequent degradation in heat of the sound wave by interference and rubbing of the air molecules against the walls of the pores of the material. Currently, a wide variety of acoustic materials that are presented in the form of plates or rolls are marketed, either in the form of a sandwich or simply in sheets, and in many cases they are formed by materials of different natures. The usual materials in acoustic applications are wood chips, wood fiber and cork, mineral wool (glass wool and rock wool); polymers: Polyester, polyurethanes, vinyl, polyethylene, methyl polymethacrylate and other less common, such as mylar and melamine; metals: steel and lead mainly; textile fibers, bitumen, asphalt and oxiasfalto and others such as concrete, glass, ceramics, clay, plaster, vermiculite, etc.

The materials currently used as acoustic absorbers are rock and glass wool. Although today they are not considered toxic, it is quite true that it is a material that eventually degrades over time, escaping into the environment in the form of fibrillar dust and therefore, by its nature, is suspected of causing toxicological problems. Thus, given the progressive hardening of toxicological regulations, it is not unreasonable to think that in the medium term these materials end up being considered as potentially dangerous, carcinogenic and triggers of other lung diseases such as silicosis, as already happened with asbestos, with whom Mineral wool is chemically related.

Different publications have revealed the possibility of using concrete or cement mortars enriched with other components that favor acoustic insulation in constructions (US patents 3,979,870; US 4,720,295 or CN patent application 1478972-A). Among these components that are added to the mortar, are residues from the oil industry. Coke is a material that originally has good conditions to be used as an acoustic absorber, derived from its physical properties: low density (real and apparent), high open porosity and configuration in the form of granular shaped particles (Frías et al, 2006 Carbon 2006 Short Abstract Number: SA-185; Sánchez de Rojas et al, 2009. Annual World Conference on Carbon, Carbon 2009, Biarritz, France, June 2009. Frías et al, 2011. Construction & Building Materials, 25: 1086- 1092). Coke offers advantages over other alternative materials. One of the advantages is the possibility of cleaning with water, while others such as fiberglass when it gets dirty loses its absorbent properties. In addition, this material can be kneaded and molded, presenting a good workability in its implementation without losing its characteristics as an acoustic absorber.

Although the high acoustic performance of coke and its potential as a possible alternative to other noise-insulating materials commonly used in the industry have been analyzed, it has not been analyzed so far its use as a coating of construction elements, such as walls or interior walls and outside.

In the case described in the invention, the coke mortar is applied as a coating on construction elements, and very advantageously on the inner face of the main wall, which functions as a support for the application of the mortar, and which is normally found in contact with the outside environment in configuration of facade walls.

On the other hand, it has been proven that the enclosures constituted by double walls with interior air chamber achieve a high acoustic insulation due to the mass-spring-mass effect. The acoustic wave transmitted between both masses (walls) is attenuated by the intermediate air chamber that functions as a spring with a stiffness K of the air. However, the reflections of the waves between the inner faces of the partitions produce a coupling between both rigid walls at a certain frequency. This phenomenon is called "resonance frequency", and is based on the natural tendency of a double partition to oscillate or vibrate, and for which the insulation capacity is reduced. To mitigate this effect and avoid a great loss of insulation in this frequency range, it is necessary to introduce absorbent material into the air chamber, in addition that the walls that make up the double sheet solution have different surface densities.

In the case of the present invention a mortar-shaped composition has been developed, such as those normally known in the field of construction, but comprising among its components an oil or coke residue. The acoustic performance of the coating described is due to a double combined effect:

a) On the one hand, it is an absorbent material as demonstrated by laboratory tests carried out with the impedance tube. However, until now, the use of cement mortar and coke to make mortars for coating construction elements on a real scale was not studied, being its use in enclosures which has allowed to verify its real applicability and great value as absorbent material of the noise in constructions and buildings. In the specific case of double wall systems with indoor air chamber, the mortar is able to attenuate the effect of the resonance frequency that occurs in the air chambers by the reflections of the acoustic waves, not only by the incorporation of an acoustic absorbent material inside the chamber, as would happen with other fibrous materials such as mineral wool, commonly used for this purpose, but also to generate a difference in thickness and surface density between the sheets that make up the partition of the building system.

b) On the other hand, this material, with a density significantly higher than that of mineral wool, applied to the inner face (or back) of one of the walls, significantly increases the mass of said wall and therefore also its insulation in what is known as the law of mass. This effect of mass increase is not achieved by mineral wool because of its low density, which is joined by the fact that the material described solves the disadvantages listed above for mineral wool.

BRIEF DESCRIPTION OF THE INVENTION

The main object of the present invention is a composition of a mortar in the form of a coating of building materials or construction elements that is composed of at least one cement matrix and a granulated carbon (coke) residue with equal particle diameters. or greater than 1 mm and equal to or less than 6 mm, the range between 2 and 5 mm being recommended and preferred, including both limits.

This coating mortar, which acts as an insulating composition of construction elements, has high performance as an acoustic absorbent (that is, it acts as an acoustic insulator when coating a construction element), for airborne noise, similar or better than that of the mineral wool and without the disadvantages mentioned above associated with this material. It has been empirically proven that the present coating mortar improves the insulation of the construction element with respect to that of mineral wool by 3 dBA. This phenomenon occurs thanks to the physical and structural properties of the coke that is added to the cement mortar (low real and apparent density, high open porosity, granular shape ...). This material, unlike mineral wool, can be washed with water and does not lose its noise attenuating properties over time.

In addition, it has been unexpectedly proven that the incorporation of the coke to the cement mortar in the lining of a construction element achieves a double effect of increasing acoustic insulation, on the one hand due to an increase in mass due to the projection of the mortar, and on the other to an acoustic absorption inside the construction element (for example, the inner chamber of a double wall system) by the porosity of the mortar applied. The acoustic performance achieved with this coating object of interest exceeds those of the same configuration of the construction element but with the incorporation of mineral wool as an insulator, and also that of conventional cement and sand mortar.

In addition, this coating that acts as an acoustic insulator additionally guarantees the waterproofing of the building to which it is applied.

The ease of application of the mortar, using projection devices and systems, also reduces the execution time on site, reducing the final costs.

The present invention also relates to the use of the coating mortar as an acoustic insulator, for example to acoustically isolate a construction element, as well as by default, the building in which said element is used.

Another object of the present invention is an interior cladding of constructive elements constituted by the coke mortar composition described above.

In the same way, another object of the present invention is constituted by a constructive element or construction material comprising a coating mortar as described herein, in any of its variants.

Likewise, the present invention encompasses the method of preparation of the cement-based mortar coating with coke, in any of its variants, comprising:

-

subject the coke to saturation in water for a period of time between 2 and 24 hours including both limits, preferably 24 hours;

-

drain the coke for a time between 15 and 60 minutes including both limits, preferably for 30 minutes; Y

-

Prepare a mixture (mortar) of cement and coke.

By subjecting the coke to water saturation in a first step, the pores of the material become occluded with water. After the saturation time, the coke drains to remove excess water. The realization of this process has the advantage of eliminating part of the fines adhered to the large particles and keeps the porosity of the material intact, thus avoiding the entry of cement into the pores during kneading. The final result of this treatment is a wet material, with pores saturated with water, which will later disappear leaving a granular aggregate that will offer a high porosity to the construction element.

DETAILED DESCRIPTION

In a preferred embodiment, the mortar is in the form of a layer, and more preferably has a thickness between 10 and 30 mm, including both limits. More preferably still, the thickness is 15 mm; this is also the preferred form in which the coating or plastering of constructive elements constituted by the coke mortar is constituted, that is, preferably in the form of a layer, more preferably with a thickness between 10-30 mm including both limits and more preferably still with a thickness of 15 mm. As can be seen, the present coating mortar has allowed the commonly used acoustic insulators of less thickness to be obtained for the industry, which saves material costs. In short, the present invention represents a very advantageous advance in the field of acoustic insulators, because it achieves a high noise absorption with significantly lower thicknesses of material. On the other hand, the lower thickness of the mortar based on cement and coke (15 mm) with respect to that of mineral wool (50-80 mm) that requires a construction element reduces the total thickness of the enclosure and therefore increases the useful surface of the building.

Also preferably, the ratio of cement matrix and coke is between 1: 1 and 1: 3 by weight of the total mortar composition, including both limits.

Preferably, although not limiting, the cement is Portland cement.

Additionally, the coke-containing cement mortar may comprise other binders and components, such as sand.

As for the construction element or construction material comprising the mortar, said element is preferably a wall or wall, more preferably still a double wall with an inner chamber, as is preferably the one used in factories, such as brick factories.

In a practical way, the cladding mortar is projected (applied) on the inner face (not seen) of the construction element, as for example it can be on the inner face of one of the walls of a double wall system (wall) with chamber interior (more preferably on the inner face of the main wall of the system or wall), increasing its effectiveness in acoustic insulation. Thus, as already noted above, a combined double acoustic effect is achieved, so that the acoustic performance of the construction element, such as this double wall construction solution with coke mortar projected on one of the inner faces, is they are significantly increased, and this has been demonstrated with comparative tests between this solution and similar ones in which the coke mortar is replaced by a conventional one of cement and sand, and in another substituted by mineral wool, as demonstrated in the Examples of This memory.

As regards the mortar preparation method, it should be noted that the ratio of cement matrix and coke is preferably between 1: 1 and 1: 3 by weight of the total mortar composition, including both limits.

The cement and coke mixture or mortar can be prepared according to conventional procedures widely known in the field.

After the preparation of the mortar, it is preferably applied by spraying on the construction element.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1. Preparation of an insulated double sheet wall with mineral wool inside, according to Example 1.

Figure 2: Preparation of a portland cement mortar and coke, according to the present invention and Example 2. Figure 2.a: Saturation in water for 24 hours; Figure 2.b: Aspect of coke after saturation.

Figure 3. Cement mortar and coke on a brick sheet on its inner face, according to the Example

2. Figure 3.a: general view; Figure 3.b: detail of the coating mortar.

Figure 4. Appearance of the cement and coke mortar after being applied to the inner face of the wall, according to Example 2. Figure 4.a: general view of the coating mortar; Figure 4.b: detail.

EXAMPLES OF EMBODIMENT OF THE INVENTION

The invention is illustrated below by tests carried out, which shows the applicability in the construction industry of the cement and coke coating mortar object of this invention, as well as its effectiveness as an airborne insulator, when compared with the behavior of a common mineral wool. A double wall partition wall solution was built with an inner chamber, where the mineral wool and the cement and coke coating mortar were incorporated.

Example 1.- Manufacture of double wall enclosure with insulated inner chamber with mineral wool.

As an example, a double wall solution of 10 m2 of double hollow partition wall with plaster plaster on the exposed faces and with the incorporation of a mineral wool inside has been executed. The materials that were used for its manufacture were the following elements:

•

double wall: Large hollow brick with 70 mm thickness.

•

acoustic insulation: Mineral wool 80 mm thick.

•

joint composition between wall and insulation: Plaster for vertical walls.

The methodology for the construction of the enclosure consisted of lifting a brick wall, plastering it with plaster paste on its inner face and gluing the mineral wool panel (Figure 1). Subsequently, the second brick partition is lifted. Finally, a laying and plaster of plaster is applied on both sides, 8 mm thick.

After lifting the double wall system, the acoustic transmission measurements of the enclosure with corresponding mineral wool were taken.

Example 2.- Manufacture of double wall enclosure with insulated inner chamber with the cement and coke coating mortar of the present invention.

After the acoustic transmission measurements of the double wall system insulated with mineral wool have been taken, one of the two brick partitions is demolished and the mineral wool is removed. The cement and coke mortar with a thickness of 15 mm is applied to the internal wall of the remaining partition wall. Therefore, the materials used are:

•

Wall: Large hollow brick with 70 mm thickness.

•

acoustic insulation: Portland cement type II 32.5 N, mixed with petroleum coke with particle diameters between 5 and 2 mm.

•

joint composition between wall and insulation: Plaster for vertical walls.

For the preparation of the mortar, given the specific characteristics sought, a treatment prior to the addition of the coke in the cementitious matrix was necessary. The coke was subjected to a saturation in water for 24 hours (Figure 2.a), sufficient time to achieve the replacement of air by water in the pores of the material; after saturation time the coke was drained for 30 minutes to remove excess water. The final result of this treatment is a wet material, with pores saturated with water, which will later disappear leaving a granular aggregate that will offer a high porosity to the construction element (Figure 2.b).

A cement mortar and coke of 1: 1.5 ratio was manufactured.

The coating mortar was applied to the zip line, covering, with a thickness of 15 mm (Figure 3.a; detail of the coating mortar in Figure 3.b).

When the cement and coke coating mortar was completed (Figure 4), the second brick sheet was lifted, which is 60 mm away from the coating mortar.

Finally, an 8 mm thick plaster cast and plaster is applied on both sides of the wall. The wall was left 28 days of curing before proceeding to the study of acoustic behavior.

Additionally, a double wall system with an inner chamber was manufactured, but with a conventional cement and sand mortar without coke.

Example 3. Comparative study of the acoustic performance mortar of comment and coke against mineral wool in double wall systems with inner chamber

To evaluate the acoustic performance of the coating mortar described here, acoustic insulation tests were performed in standard laboratory chambers (UNE EN ISO 140 parts 1 and 3 standards), both of the system prepared in example 1 and usually used in the current building of double wall with mineral wool insulation in the inner chamber, as proposed here in Example 2, in which the mineral wool is replaced by a 15 mm thick coke mortar projection and another one in which mortar is used Conventional cement and sand.

The results obtained, evaluated according to the UNE EN ISO 717-1 standard, show an increase in acoustic insulation of 3 dBA in the solution that incorporates the cement and coke mortar in the trasdós with respect to the mineral wool solution (global insulation RA = 50 dBA for the coke solution and RA = 47dBA for that of mineral wool) and 2dBA with respect to which incorporates conventional cement and sand mortar (RA = 48dBA for that of conventional mortar).

Claims (17)

one.

 Coating mortar of construction elements characterized in that it comprises at least one cement matrix and granulated coke with particle diameters between 1 and 6 mmm, including both limits.

2.

 Coating mortar according to claim 1, characterized in that the granulated coke has a diameter between 2 and 5 mm, including both limits.

3.

Coating mortar according to any one of claims 1 or 2, characterized in that it has a proportion by weight of cement and coke comprised between 1: 1 and 1: 3 by weight of the total mortar composition, including both limits.

Four.

 Coating mortar according to any one of claims 1 to 3, characterized in that the cement is Portland cement.

5.

 Coating mortar according to any one of claims 1 to 4, characterized in that the mortar comprises at least one binder.

6.

 Coating mortar according to claim 5, characterized in that the binder is sand.

7.

Interior cladding of constructive elements constituted by the mortar described in any one of claims 1 to 6.

8.

 Coating according to claim 7, characterized in that it is presented as a layer.

9.

 Coating according to any one of claims 7 or 8, characterized in that it has a thickness between 10 and 30 mm, including both limits.

10.

Coating according to the preceding claim, characterized in that it has a thickness of 15 mm.

eleven.

 Method of preparing a coating mortar according to any one of claims 1 to 6, comprising:

-

subject the granulated coke to saturation in water for a period of time between 2 and 24 hours;

-

drain the coke for a time between 15 and 60 minutes; Y

-

Prepare a mixture of cement and drained coke.

12.

Method according to claim 11, wherein the ratio of cement and coke matrix is preferably between 1: 1 and 1: 3 by weight of the total mortar composition, including both limits.

13.

 Method according to any one of claims 11 or 12, characterized in that the granulated coke is subjected to saturation in water for 24 hours.

14.

 Method according to any one of claims 11 to 13, characterized in that the coke is drained for 30 minutes.

fifteen.

Double wall with inner chamber and acoustic attenuation function, characterized in that it comprises the coating mortar described in any one of claims 1 to 6 applied on the inner face of the main wall that is in contact with the outside environment in configuration of facade walls, and that works as a support for the application of the mortar.

16.

 Use of a coating mortar according to any one of claims 1 to 6 as an acoustic insulator of airborne noise in construction elements.

 SPANISH OFFICE OF THE PATENTS AND BRAND Application no .: 201131115  SPAIN Date of submission of the application: 01.07.2011 Priority Date:  REPORT ON THE STATE OF THE TECHNIQUE 51 Int. Cl.: C04B14 / 36 (2006.01) RELEVANT DOCUMENTS

Category

56 Documents cited Claims Affected

TO

GB 1541111 A (INT CONSTR PROD RES) 21.02.1979, 1-16

claim 1; figure 3.

TO

WPI DATA BASE IN EPOQUE, AN 2005-525997, 1-16

JP 2005194168 A (TAIHEIYO MATERIAL KK) 21.07.2005, summary.

TO

WPI DATA BASE IN EPOQUE, AN 2001-548622, 1-16

KR 20010028977 A (HANIL CEMENT MFG CO LTD) 06.04.2001, summary.

TO

WPI DATABASE IN EPOQUE, AN 1998-357290, 1-16

JP 10139518 A (NIPPPON STEEL CHEM CO) 26.05.1998, summary.

Category of the documents cited X: of particular relevance Y: of particular relevance combined with other / s of the same category A: reflects the state of the art O: refers to unwritten disclosure P: published between the priority date and the date of priority submission of the application E: previous document, but published after the date of submission of the application

This report has been prepared • for all claims • for claims no:

Date of realization of the report 03.12.2012

Examiner J. García Cernuda Gallardo Page 1/4

 REPORT OF THE STATE OF THE TECHNIQUE  Application number: 201131115 Minimum documentation sought (classification system followed by classification symbols) C04B Electronic databases consulted during the search (name of the database and, if possible, terms of search used) INVENES, WPI, EPODOC, XPESP, TXTEP1, TXTGB1, TXTUS2, TXTUS3, TXTUS4 State of the Art Report Page 2/4  WRITTEN OPINION  Application number: 201131115 Date of Written Opinion: 03.12.2012 Statement

Novelty (Art. 6.1 LP 11/1986)

Claims Claims 1-16 IF NOT

Inventive activity (Art. 8.1 LP11 / 1986)

Claims Claims 1-16 IF NOT

The application is considered to comply with the industrial application requirement. This requirement was evaluated during the formal and technical examination phase of the application (Article 31.2 Law 11/1986).  Opinion Base.- This opinion has been made on the basis of the patent application as published. State of the Art Report Page 3/4  WRITTEN OPINION  Application number: 201131115  1. Documents considered.- The documents belonging to the state of the art taken into consideration for the realization of this opinion are listed below.

Document

Publication or Identification Number publication date

D01

GB 1541111 A (INT CONSTR PROD RES) 21.02.1979

D02

JP 2005194168 A (KI TAIHEIYO MATERIAL) 07/21/2005

D03

KR 20010028977 A (HANIL CEMENT CO LTD) 06.04.2001

D04

JP 10139518 A (NIPPON STEEL CHEMICAL CO) 05/26/1998

 2. Statement motivated according to articles 29.6 and 29.7 of the Regulations for the execution of Law 11/1986, of March 20, on Patents on novelty and inventive activity; quotes and explanations in support of this statement The application refers to a mortar for coating construction elements comprising at least one cement matrix and granulated coke with particle diameters between 1 and 6 mm (reiv. 1). The proportion by weight of cement and coke is between 1: 1 and 1: 3 by weight of the total mortar composition (reiv. 3). Rev. 7 refers to an inner lining of construction elements constituted by the mortar. The reiv. 11 to a method of preparation of the coating, subjecting the granulated coke to a saturation in water for 2 to 24 hours, drained from the coke and preparation of a mixture of cement and the drained coke. The reiv. 16 to the use of mortar as an acoustic insulator of airborne noise in construction elements. Document D01 refers to the inhibition of contraction in cement systems by mixing hydraulic cement with a carbonaceous material that occurs naturally and water. According to Fig. 3. the carbonaceous material can be coke fluid. Coke is not expected to be granulated and the application is not for acoustic insulation, but for inhibiting contraction in setting. Document D02 refers to a cement mixing material containing a porous material, an expansive additive, an agent to prevent separation and a water reducing agent. Preferably, the porous material is coke. Coke is porous, not granular, and the application of the material is to confer fluidity, dimensional stability and resistance to breakage, not for acoustic insulation purposes. Document D03 refers to a mortar composition that shows no shrinkage in drying comprising 21-23 parts by weight of cement, 69-72 parts by weight of sand, 3-4 parts by weight of fly ash, an agent for increase the viscosity and 0-5 parts by weight of an expansion control agent consisting of a mixture that includes 30-50% limestone and 50-70% coke. It includes components other than those of the application and the coke is not granular nor is the product intended for sound insulation. Document D04 refers to an acid-resistant hardening agent in Portland cement. It contains a group of coal or calcined coke and mortar or concrete. No data are provided on the granular nature of the coke or its size, and it is intended to improve resistance, not acoustic insulation. The application is considered to meet the requirements of novelty and inventive activity in its claims 1-16, according to art. 6.1 and 8.1 of the L.P. State of the Art Report Page 4/4