Hennebique Const. Co. v. Armored Concrete Const. Co.

163 F. 300, 1908 U.S. App. LEXIS 5230
CourtU.S. Circuit Court for the District of Maryland
DecidedJanuary 28, 1908
StatusPublished
Cited by2 cases

This text of 163 F. 300 (Hennebique Const. Co. v. Armored Concrete Const. Co.) is published on Counsel Stack Legal Research, covering U.S. Circuit Court for the District of Maryland primary law. Counsel Stack provides free access to over 12 million legal documents including statutes, case law, regulations, and constitutions.

Bluebook
Hennebique Const. Co. v. Armored Concrete Const. Co., 163 F. 300, 1908 U.S. App. LEXIS 5230 (circtdmd 1908).

Opinion

MORRIS,' District Judge.

This is a bill of complaint,, in usual form, charging infringement of a patent belonging to complainant, and praying for an injunction and an account. The bill alleges that, prior to. December 29, 1897, Francois Hennebique, a citizen of France, was the inventor of certain improvements in the construction of joists, [301]*301girders, and the like, and that upon his application, filed December 29, 1897, there was granted to him, in due form of law, patent of the United States, dated October, 1898, No. 611,907, for improvements in the construction of joists, girders, and the like of'cement strengthened with iron. This patent, by valid assignment, has become the property of the complainant, the Hennebique Construction Company. The specifications and claims of the patent are as follows:

“The use of strengthened, betón in buildings has within recent years greatly developed. It has been thought possible, by mixing b-eton and iron or steel, to replace the purely metallic elements of building construction by parts equally incombustible, but lighter, and more simply and rapidly made. In any case the mixture of cement or hydraulic lime, which resists perfectly compression, with iron or steel, which more particularly resists tension and flexion, has not hitherto been capable of being carried out in a judicious and rational manner. By arranging at useful points in a mass of betón of suitable form longitudinal bars of iron of a given shape in order to constitute the tension chord, by distributing them in the mass in a judicious manner in order that the whole mass of iron and betón may have at every point of the piece formed the desired resistance to flexion and tension, and by further connecting the longitudinal bars by brace pieces or stirrups of suitable form, I have succeeded in producing the practical joists, girders, and the like which form the object of my present invention.
“The invention is illustrated in the accompanying drawings, in which I have shown diagrammatically in Figure 1 a practical continuous joist or girder of betón strengthened with iron arranged according to these principles. Figure 2 is a detail perspective view of one of the stirrup pieces. Figure 3 is a section on line, s, t, of Figure 1. Figure 4 is a sectional perspective on line, x, y, of Figuire 3; the longitudinal half of the girder being supposed to be removed. Figure 5 is a detail illustrating the construction at the point of passing an intermediate support. This joint, incased or built in at one of its ends, A, is placed on a series of intermediate supports, C. The characteristic of the metallic core or strengthening is the addition to longitudinal bars, 1, arranged parallel to the lower side of the joist, of inwardly-bent bars, 2, 2', 2", 2’", arranged in the same vertical plane. These bars are parallel to the bars, 1, in the mean central part of the joist; that is to say, in the part where the effects of tension are almost nothing. They are placed parallel to the bars, 1, and in their vicinity they double the resistance of the latter to tension. They are carried by the same supports or stirrups, 3, and these latter thus connect the chord of tension formed by the bars with the chord of compression formed by the betón. One -of these stirrup pieces is shown in perspective in Figure 2. It is formed of a band of sheet iron of TJ shape having straight arms, terminated by a little hook, which facilitates their fixing in the betón. These straight stirrup pieces play in the joist of strengthened betón the part which the suspension rods play in the trussing of metallic girders.
“As in the extreme parts of the girder the tension action increases in proportion as the wall, A, and the support, O, are approached, I raise the bar, 2. The inclined arms, 2', of this bar, are connected with the horizontal bar, 1, by stirrup pieces, 3, approached more and more closely together. I thus form a triangle of resistance, the apex of which is at the point of divergence of the bars, 2'. This triangle, in consequence of the stirrup pieces, 3, being progressively placed nearer one another, and of the growing mass of betón which it incloses between the bars, 1 and 2', offers a proportionate increasing resistance to the tension action. Each bar, 2, is inclined upwardly at 2', runs horizontally, as shown at 2", and is extended beyond the incline of the adjacent bar, as shown at 2'". At the point where the continuous girder passes on to an intermediate support, C, I prolong the bar, 2", to 2'", in the adjoining compartment or1 bay, which is thereby strengthened; and in order to insure that the reaction of the betón of this prolongation shall not raise the latter I crown it with reversed stirrups, a, which maintain the bar perfectly firm.
“Figure 5 shows in detail the passing over an intermediate support, C. The crossing of the arms, 2"', consolidates the girder in a practical manner on [302]*302tile support, C, where the bending strain is greatest. It will be seen, therefore, that owing to the addition of a single bar, 2, the arms, 2', 2", 2"', of which are suitably inclined, connected, and arranged in the betón, and, further, owing to the rational distribution of the straight stirrup, 3, it is possible to construct girders resistant in all their parts in a perfect manner to the effects of tension, the effects of compression, the breaking effects, and the bending effect, while reducing to a minimum the quantity of iron employed, and suppressing or dispensing with iron in the part under compression, thereby avoiding between the irons, 1 and 2, any cross-fastening by inclined stirrups or by wire lattice work. It is needless to state that the principles herein described may be applied to the manufacture of any suitable girders or joists for ceilings or floors, and in fact, to any constructions formed of betón strengthened with metal, which, as regards the strains which they will support, may be likened to girders placed on supports or incased in masonry. It is also understood that according to the dimensions of the girder, the transverse section of which is not necessarily rectangular, the number of bars, 1 and 2, placed in the same vertical plane, may vary.
“Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is:
“1. In the construction of joists, girders, and the like of cement strengthened with iron or the like, the inwardly-bent bars, 2, 2’, 2", 2”’, of which the central branch, 2, is horizontal and arranged in the plane of the bar, 1, which forms the chord of tension of the girder, and of which the arms, 2', are always raised in the same vertical plane and in the direction of the point where they are fitted into the wall, A, or on the supports, O, in order to obtain a better resistance to the increasing breaking strain, while the branch, 2'', is extended into the next span, substantially as described.
“2. In the construction of joists, girders, or the like of the kind described, the straight stirrup pieces, 3, of hoop iron in a Ü form for connecting the bars, 1, and the inwardly-bent bars, 2, 2', 2", 2"', the said stirrup pieces being distributed in the girder, substantially as hereinbefore described.”

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Related

Hennebique Const. Co. v. Urban Const. Co.
182 F. 496 (Eighth Circuit, 1910)

Cite This Page — Counsel Stack

Bluebook (online)
163 F. 300, 1908 U.S. App. LEXIS 5230, Counsel Stack Legal Research, https://law.counselstack.com/opinion/hennebique-const-co-v-armored-concrete-const-co-circtdmd-1908.