US3494087A

US3494087A - Framing of joists in buildings

Info

Publication number: US3494087A
Application number: US608910A
Authority: US
Inventors: Per-Olof Jonell; Sven Melker Nilsson
Original assignee: OLOF JONELL
Current assignee: OLOF JONELL
Priority date: 1966-01-25
Filing date: 1967-01-12
Publication date: 1970-02-10
Anticipated expiration: 1987-02-10
Also published as: FI44160B; DE1683059A1; DK133705C; NO121175B; SE314790B; FR1509430A; DK133705B

Description

Feb. 10, 1970 PER-O. ON ETAL 3,494,087

FRAMING OF JOIS'IS IN BUILDINGS 2 SheetsSheet 1 Filed Jan. 12, 1967 Fig.2

4 H H F 1N VE N TOR-S Feb. 10, 1970 PER-OLGF JONELL ET AL FRAMING OF JOISTS IN BUILDINGS 2 Sheets-Sheet 2 Filed Jan. 12, 1967 INVENTO S United States Patent 3,494,037 FRAMING OF JOISTS IN BUILDINGS Per-Olof Jonell, Engelbrektsgatan 24, Goteborg, Sweden,

and Sven Melker Nilsson, Radhusvagen 6, Kallered,

Sweden Filed Jan. 12, 1967, Ser. No. 608,910 Claims priority, application Sweden, Jan. 25, 1966, 917/ 66 Int. Cl. E04f 15/18; E04b 1/8 U.S. Cl. 52-403 5 Claims ABSTRACT OF THE DISCLOSURE The present invention has reference to an improved framing of joists having and intermediate layer of a soft material specially shaped for giving a good sound insulation and having a low weight, while providing a two-stage shock-absorbing or compressibility factor under predetermined loads wherein the intermediate layer is of a construction and form whereby the initial compression of said layer is greater for given smaller loads applied thereto than the subsequent or second stage compression for given greater loads applied thereto.

Framings of joists for house building purposes may in the same way as walls be shaped either as a single or double construction. In the first case there is required e.g. in concrete framing of joists a weight of the same of at least 350-400 kg./m. if the requirements of a noise insulation should be fulfilled in Sweden. In the second case the weight of the framing of joists can be reduced in different degrees according to the type of construction. The layer situated between the upper construction portion, i.e. the floor proper, and the lower portion which often comprises a supporting portion is then of great importance. The purpose aimed at from the point of view of noise insulation is in this case that the intermediate layer should be as soft as possible. When there is a question concerning walls which as a rule are not exposed to great laterally directed forces, the intermediate layer may in the practice be formed so soft that only the requirements on sound insulation will influence the dimensioning. In practice the layer often comprises only an air layer. However, when there is a question of framings of joists, the conditions will be more complicated. In this case the intermediate layer must be apt to absorb vertical stresses entered into the framing of the joists without causing the floor covering, e.g. a linoleum floorcloth, to burst or be damaged in any other way when these forces must be taken into consideration when dimensioning the softness of the intermediate layer.

The present invention has reference to a framing of joists which is composed of a supporting lower portion and an overlaying fioor construction comprising e.g. a thin concrete slab and an intermediate layer of an elastic material. The main feature of the invention is to be seen therein that the resilient device between the floor construction and the lower portion is shaped in such a way that the downward deflection or compressibility-as seen from the original positionfor a certain charge or load increase will be considerably greater for small loads on the floor construction than for high ones. The springing or resistance between the floor construction and the lower portion will be so soft that the noise insulation requirements can be fulfilled in spite of a very low weight of the framing of joists. At small loads, say 50 kg./rn. on the framing of joists, the springing can be made many times greater than at loads above this value. For 50 kg./m. the springing may be eg about 1 millimeter but for a further load of 50 kg./m. only 0.1 millimeter. In

3,494,087 Patented Feb. 10, 1970 this way it is possible to obtain a very good air and step noise insulation with a rather low weight of the framing of the joists, about kg./m. When the load increases to such a value that it exceeds a value for which the springing is soft, the springing does no longer have to be so soft for the reason that the increasing load gives a sound insulating effect which compensates the losses due to the harder or less resilient springing.

The invention will in the following be elucidated with reference to the accompanying drawing showing a number of embodiments of the invention. In the drawings:

FIG. 1 is a side elevation of a joint between two concrete cassettes in a framing of joists provided with a device according to the invention,

FIG. 2 shows on an enlarged scale on the one hand a side elevation and on the other hand a vertical section through one of the cassettes,

FIG. 3 shows a similar section but when the floor construction is exposed to load,

FIG. 4 shows a section similar to the one in FIG. 2 but according to another embodiment of the invention,

FIG. 5 is a plan view of one corner of the resilient intermediate layer shown in FIG. 2,

FIG. 6 is a similar view of an intermediate layer but according to another embodiment,

FIG. 7 shows on an enlarged scale a vertical section through one side of the framing of joists with a resilient intermediate layer according to a further embodiment, and

FIG. 8 shows on an enlarged scale a vertical section through the upper left hand corner of the embodiment shown in FIG. 2.

The framing of joists shown in the drawings is shown to comprise a number of elements 1, 2 arranged close to each other and being carried at their ends by a cross beam, a wall or a similar supporting element 3. In the space 4 between the elements 1, 2 there is inserted a tightening or tieing means comprising an elastic material, e.g. synthetic resin, in the shape of a hose 5 which from one end has been filled with a curing mass 6, e.g. concrete or synthetic resin. Each element 1, 2 comprises a bowl-shaped concrete cassette 7, a thin layer 9 011 its upper smoothed border 8 of any soft, resilient material such as cork, foamed plastics, rubber or the like and a thin concrete slab 10 covering the cassette or any other suitable floor construction. The slab 10 is self-supporting between the four side walls 11 of the cassette and rests on the resilient intermediate layer "9.

According to the embodiment shown in FIG. 2 the intermediate layer 9 is provided with a ridge or bulge 12 extending in the longitudinal direction. The width b (FIG. 8) and the height h of this ridge 12 is chosen in such a way that the desired softness is obtained for a certain load, e.g. 50 kg./m. When this load is exceeded, the ridge 12 will be pressed down into the elastic intermediate layer and the slab 10 will thereupon rest over the whole width B of the intermediate layer 9 (FIG. 3). The height of the ridge 12 is chosen small, about 1 millimeter. The value is chosen such that detrimental remaining deformations cannot occur in the intermediate layer.

According to the embodiment shown in FIG. 4 the slab 1 0' is on its under side provided with a bulge 13 situated close to the outer border and extending along said border. The dimensions of this bulge are chosen in such a way that at the predetermined low load, e.g. about 50 kg./m. the bulge 13 will be pushed practically completely down into the elastic intermediate layer 9 and at an increasing load the slab 10" will rest in flat shape against the whole upper side of the intermediate layer.

An analogous result can be obtained if instead the lower side of the intermediate layer 9 is provided with said bulge 12. One or several bulges may be provided and these bulges can be formed by providing notches in the upper or/and lower surfaces of the layer. At a certain low load the slab rests against only the upwardly extending bulges against the upper border of the cassettes 7 and resiliency will then be very soft, At a greater load the bulges are pressed into the intermediate layer and the slab will then rest against the whole width of the intermediate layer or this layer with the whole of its width against the upper border of the cassettes.

The embodiment shown in FIG. 6 is provided with bulges comprising abutment 14 of a low height, e.g. l millimeter. The transverse dimensions of the abutments 14 and their mutual distance are chosen in such a way that the abutments at the low load in question will be pressed practically completely into the intermediate layer 9 and at an exceeding of this load the slab 10 will rest on the whole of the upper side of the intermediate layer.

According to a further embodiment (FIG. 7) the intermediate layer 9 comprises a strip of cork or cardboard and there is on one or both sides of this strip attached a layer of grains of sand with a size of the grains of about 1 millimeter in diameter. The sand grains may with advantage be attached to the intermediate layer 9 by means of a bituminous binding agent. The distance between the grains is chosen in the same way as described in the aforegoing in connection with the abutments 14 on the intermediate layer 9 according to FIG. 6.

According to FIG, 1 there is shown on the concrete slab 10 of the elements 1 and Z a linoleum floorcloth 16. Due to the rather low springing down at high loadsthere is as a rule a question of a resiliency in downwards direction of about 1 millimeter-there is no risk that the fioorclothing will burst at the joint between the elements.

The invention has been described in the aforegoing for purposes of illustration only and many modifications are possible within the scope of the appended claims. Thus, the element parts 1, 2 as well as the intermediate layer 9 on the same way may be shaped in many different ways. Also other materials than the ones mentioned in the foregoing could be used for the construction details mentioned. It is also possible to arrange the ridges, the bulges and the abutments on the upper side of the walls 11 of the cassettes.

What we claim is:

1. A framing of joists comprising a primarily supporting lower portion, a floor construction, an elastic intermediate layer supporting said floor construction on said lower portion, and resilient means between said floor construction and said lower portion so shaped that the downward give of said floor construction, as seen from the original position, for a certain load increase will be considerably greater for smaller loads on the floor construction than for higher loads, and wherein there are provided projections between said floor construction and lower portion having surfaces carrying said floor construction when under small loads, and said projections being compressed into the rest of said elastic intermediate layer at a certain load increase.

2. A framing of joists as defined in claim 1 wherein said projections comprise grains embedded in said elastic intermediate layer, said grains, when the floor construction is in an unloaded condition, extending with a part of their volume outside of a surface of said intermediate layer.

3. A framing of joists as defined in claim 1 wherein said projections are formed directly on said elastic intermediate layer in the shape of abutments.

4. A framing of joists as defined in claim 1 wherein said projections are formed directly in said intermediate layer in the shape of a plurality of compressible bulges.

5. A framing of joists as claimed in claim 1 wherein said projections are provided On the underside of said floor construction.

References Cited UNITED STATES PATENTS 926,773 7/1909 Schirra 52-445 2,425,567 8/ 1947 Robinson 248-22 2,962,183 11/1960 Rill et 211.

3,332,646 7/ 1967 Kellett 248-22 498,344 5/ 1 893 Williams 5 2-403 1,937,186 11/1933 Barrett 52-502 2,746,097 5/1965 Tofani 52-403 FOREIGN PATENTS 730,018 3/ 1966 Canada.

472,499 9/ 1937 Great Britain.

554,818 7/1943. Great Britain.

FRANK L. ABBOTT, Primary Examiner J. L. RIDGILL, JR., Assistant Examiner iU.S. Cl. X.R. 52-414