US1688305A - Reenforced concrete cribbing - Google Patents

Description

Oct. 16, 1928. 1,688,305

.I. M. FITZGERALD REENFORCED CONCRETE CRIBBING F'iled Oct. 30, 1925 2 Sheets-Sheet 1 v zfl ll for. 7521/ 71/ raazi Oct. 16 J. M. FITZGERALD REENFORCED CONCRETE CRIBBING Filed Oct. 50, 1925 2 Sheets-Sheet 2 Patented Oct. 16, 1928.

JOHN M. IEI'1ZGERALD, OF RIVER FOREST, ILLINOIS.

BEENEOBCED CONCRETE GBIBIBING.

This invention relates to new and useful improvements in reenforced concrete cribbing of pre-formed units, and more particularly to improvements upon the type of crlbbing illustrated in the patent to Robert H. Ford, et all, No. 1,312,689, dated August 12, 1919, although it may be applied to other types of concrete cribbing.

In the patent referred to the spaces between the superposed layers of stretchers in the cribbi'ng wall are substantially equal to the dimension of the stretcher; that is to say, if the stretcher body is 5" by 5", the space between the bottom surface of the stretcher member and the top surface "of the next subjacent member will be approximately 4, and this distance is increased when certain other types or forms of headers and stretchers are use It is found that the natural angle of repose of the filling material is such'that when cribbing of this general type is used, the earth, especially if of a sandy character, spills through the open-in s and is carried away too freely by water.

invention is to provide spaces in the cribbing wall which shall be sufliciently large to per-T mit the passage of the water and yet substan-- tially prevent the improper passage of the filling material therethrough. p To this end the invention consists in the construction illustrated and described and more particularly pointed out in the appended claims.

In the drawings:

Figure 1 illustrates in a perspective view, a cribbing composed of units embodying the invention, but with the filling material omitted.

Figure 2 is a front elevation of the crib wall 40 showing the stretcher units in side view and the header units in end view. 1 v

Figure 3 is a view in elevation showing the superposed header units without the stretchers.

Figure 4 is a transverse, sectional View, enlarged, through the superposed stretcher units,-the section being taken in the plane of the vertical line a 'a of Figure 2.

Figure 5'is a view similar to Figure 4 but showing a modification in construction of the stretcher units.

ne of the objects of this.

Application filed October 30, 1925. SeriafNo. 65,729.

Figure 6 is a transverse, sectional view, enlargZd, of one of the stretchers shown in Figure In the particular form of cribbing units which I have chosen to illustrate the present invention, it will be seen that the cribbing is composed of a plurality of courses of headers 19 and stretchers 13, so disposed that the varlous courses composed of stretchers and interlocking header ends,.lie in a vertical row or wall, while the headers proper extend, transversely, in another vertical row, thus forming the cellular cribbing. structure.

The headers 10 consist of properly reenforced concrete, of the desired predetermined size, both as to length and cross section. As

shown, and preferably, the body of the header is substantially rectangular in cross section. Each header is formed at one or both ends with laterally-extending flanges 11, 11,Which give a T-shaped form to the header end. These flanges are flush at one end with the top surface of the header body, but extend below the bottom surface of the ,header,this downwardly extending portion 12 constituting an integral spacer member.

The stretchers 13 are also composed of reenforced concrete of predetermined length and dimensions. The body of the stretcher is also,

preferably, substantially rectangular in cross section, and the same size as the body of the header. As shown, the ends of the stretchers 13 are provided with kerfs 1 1 which are adapted for interlocking connection with the flanges constituting the T-shaped end of the header. The stretcher ends are also provided with a spacer member 15 integral with and extending downwardly below the lower surface of the stretcher body. The spacer members 15 and'12 are substantially of the same vertical dimension.

Some of the stretchers, it will be observed, are longer than others, and this permits of laying the courses in what is familiarly known as a break joint construction, as clearly seen in Figs. 1 and 2. When it is desirable to break joints, itis found to be convenient to place on the long stretchers intermediate their ends, a downwardly extending lug or portion 16 of the same height as the stretcher member 15.

Depending from the bottom surface of the stretchers is a curtain 17 which, as shown in Figs. 2 and 4, has a front face or wall 8 coin cident with the front face f of the stretchers. Said curtain is wider at its top where it joins the lower face of the stretcher than at its bottom edge 18, and is of less height than the height of the extensions 15, 16, as clearly indicated in Figs. 2 and 4, thereby leaving between the lower edge 18 and the top surface of the next subjacent stretcher, a relatively narrow opening or space 19. This lower edge 18 extends inwardly a relatively short distance, as clearly seen in Fig. 4, and the back surface of the curtain is given a slope or inclination upwardly and rearwardly until it joins the lower surface 20 of the stretcher at a point considerably within the rear face r of the stretcher.

By this arrangement, it will be seen by reference to Fig. 6, that the angle of repose of the filling material, indicated by the dotted line 21, touches the corners 22 and 23 of the stretcher and the curtain respectively, and strikes the top surface of the subjacent stretcher at the point 24, well within the front face 7 of the stretcher wall. The construction described has the advantage of bringing the filling material to rest upon the top surface of the stretcher at the point 24, so far within the front face that the filling will not normally spill out through the openlngs 19.

It will be noted that the angular rear surface of the curtain 17 and the bottomsurface 18 of the stretcher define a triangular air space above the angle of repose line, WhlCh will effectually accommodate additional filling material which may result from freezlng or other temporary causes. Thus the normal lateral pressure of the filling material comes against the rear face 1' of the stretcher, past the corners 22 and 23, and upon that part of the top surface of the stretcher in rear of the point 24. Any undue or occasional lateral pressure against the angular rear face of the curtain 17 is reduced to a negligible quantity and practically entirely avoided.

By this arrangement it is found that a very strong construction is produced and that i there is no tendency of the curtain proper to crumble, crack or break, while at the same time a sufficient opening 19 is at all times present to take care of seepage.

I have thus far described the curtain structure of Figure 4 where the front surface 8 of the curtain is flush with the front surface 7 of the wall of which the stretchers are a a part. In Figure 5, I have illustrated just the reverse construction,that is to say, the long dimension surface s of the curtain 17 is flush with the rear surface 1' of the stretchers of, the same wall, and the angular surface of the curtain extends upwardly and forwardly from its lower edge 18 to the front face f of the stretcher.

The space 19 permits seepage of water, as

"space between the before, while the curtain 17 effectually prevents any improper spilling of the filling material.

In the two forms shown in Figs. 4 and 5, we have the decided advantage of the stretcher being of cross-sectional area of the minimum size required for strength, and provided with an integral depending curtain so as to form in the wall, spaces 19 of minimum size; the shape of the curtain resulting in saving a very considerable quantity of concrete material, while providing a curtain of the desired strength.

There may be instances where it will not be necessary to apply the curtain 17 to the header units, and on the other hand, there are instances where it may be highly desirable to do so. One of such uses is illustrated in the end wall at the right hand side of Fig. 1.

Slight modifications ma be made in the details of construction by t ose skilled in the art, since it will be obvious that the curtain 17 may be readily applied to formsof concrete cribbing units other than the specific form illustrated herein.

Again, I have described the curtain 17 as depending from the lower face of the stretcher body, but manifestly, it may extend upwardly from the top surface thereof.

I desire to have it understood that such and other modifications and uses are embraced within the scope of the invention as set forth in the claims appended hereto.

I claim as my invention:

1. A concrete cribbing of pre-formed, superposed headers and stretchers having elongated substantially rectangular body portions, each header having a T-shaped end adapted for self-interlocking engagement with stretcher ends, and a curtain integral with the stretcher and extending longitudinally between the stretcher ends, said curtain being of less depth than the depth of the superposed stretchers, and of a width less than that of the stretcher body, and tapered on its inner surface.

2. A concrete cribbing of pre-formed, superposed headers and stretchers having elongated substantially rectangular body portions adapted to retain filling materialwithin the cribbing, each header having a T-shaped end adapted for self-interlocking engagement with stretcher ends, and a curtain integral with the stretcher, extending longitudinally thereof between its ends, the front of the curtainand the front of the stretcher body bein flush, and the rear surface of thecurtain icing inclined ina plane forwardly of the natural angle of repose of the fill.

3. A concrete cribbing unit com rising an elongated substantially rectangifiar body portion having depending body spacer portions, and a relatively narrow curtain ortion of less depth than said spacer portions extending longitudinally of said body portion between said spacer portions.

4. A concrete cri bing unit comprising an elongated substantially rectangular body 5 portion having depending body s acer rtions, and a curtain portion of less e th t an said spacer portions and of less wi th than said body portion depending from said body portion flush with one face thereof, the opposite face of said curtain bein inclined.

In testimony that I claim t 1e foregoing as my invention I aflix my signature this 28th day of Octo ber, 1925.

JOHN M. FITZGERALD.

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