US 2128480 A
Description (OCR text may contain errors)
.Aug. 30, 1938. L. s. WER-rz REINFORCING cNoRETE PATCH Filed June 15, 1936 ATTORNEYS Patented Aug. 30, 1938 UNITED s 'rATEs PATENT ori-ICE Louis s. wem, rshaker Heights, om
Application June 15, 1936, Serial No. 85,236
This invention relates to the restoration of concrete structures and has particular reference 12 Claims.
to the reinforcing of a concret-e patch. In concrete construction, whether in new work or in the restoring of old structures, it is desirable to provide reinforcement within the structure to Awith-- stand tensile stresses.
in the structure.
This is usually done by an arrangement of steel rods or wires embedded In order that these reinforcing members be enicient they should take up any tension to which the concrete in which they are embedded may be subjected. Where a concrete patch has been applied to a concrete structure, tensile stresses, such as induced by temperature changes, are apt to cause cracks or fissures in the patch and particularly in the bond between the new and old concrete. It is, therefore, an object of this invention to provide a method of reinforcing .concrete used in the restoration of structures so that the new concrete will be relieved of substantially al1 tensile stresses and to avoid as'far as possible, the formation of such cracks.
Another object of this invention is to provide a method of reinforcing concrete used in the restoration of structures which will minimize voids or spaces between the new concrete and the old structure.
Another object is to prvide an improved anchor to be used in reinforcing replacement concrete and which may be used independently and which will take the tensile stresses between the new and old concrete.
A further object of the invention is to provide a method of reinforcing replacement concrete so that in addition to the bond afforded between the two concretes, it will be adequately anchored to the old structure.
ity not completely filled;`
Fig. 2 is a section on the line 2--2 of Fig. 1; Fig. 3 is a detail in section showing the manner in which the anchors are secured in the structure Fig. 4 is aperspective of a portion of an anchor showing the manner of connecting the reinforcing network thereto; and
Fig. 5 is a perspective of an i ing anchor.
mproved reinforc- Referring to the drawing by numerals of reference, it will be seen that the invention comprises a tensioned network I0 which may be formed of any suitable material having adequate tensile properties, such as steel, preferably in the form of wire.
In restoring concrete structures it is preferable to rst chip away the loose scale and disintegrated portions of the structure, so that the surface Il of the old structure adjoining the cavity to be filled will be firm and hard. In order that the marginal portions of the patch will not be tapered to a thin or feather edge, it is desirable to remove suflcient of the old structure so that around the marginal portion or contour of thel region to be patched there is room for a substantial depth of new concrete. When one or more portions of the cavity to be nlled with new concrete are of considerable depth such as indicated at 23, it is preferable to employ anchoring devices 21 of improved design, shown in perspective in Fig. 5. They comprise a body portion formed with an upset end 28 provided with an expansion collar 29, and an expanding wedge 30. The opposite end of the body portion is formed into a loop 3|. Crossarms 33 and 34 have a centrai portion positioned in and have their ends I extending radially from the aperture of the loop 3 I. In some cases it may be desirable to weld the crossarms 33 and 34 in the loop 3l. These anchors or reinforcing trees. having an elongated body portion, are placed in the deep cavity portion 25 at suitably spaced intervals, such for example as a distance between centers of four times the height of the individual reinforcing anchors. With the secondary reinforcing anchors in position, new concrete is applied to the old concrete in the deep portions 25 of the cavity so that the secondary anchors are substantially embedded therein and serve to hold the new con- '40 crete in position While it is setting, as well as at one end of the shank I6, and the opposite end 'serving to reinforce the structure after the new out of the expansion head I8, when the latterll I'I is provided with any suitable means to hold it within a recess formed in the'concrete, such as.
the upset end I1, which prevents its being pulled at suitable spaced intervals. These intermediate anchor bolts engage the network III, preferably at an intersection of individual wires 22, and thereby serve to prevent deflection of the reinforcing network III and tie in the entire mass of replacement concrete Il to the old concrete I2.
The reinforcing network I comprises a number of individual rods or wires 22 which may be suitably secured together at their intersections such as by spot welding to prevent relative movement and to more effectively reinforce the new concrete. I'his network is formed to approximate the shape of the cavity to be filled. The tensioning of the network is preferably accomplished by means of tie-wires 26 which are looped about the wire retaining hook II of the tension anchors and about an individual wire 22 of an adjacent portion of the reinforcing network III. When the network is thus suspended in the cavity the tire-wires 28 may be twisted by means of a suitable implement such as a nail inserted in the loop of the tie-wire, or otherwise tensioned to hold the network tightly in place. 'I'he reinforcing network Ill may be tied in or otherwise secured to the anchoringv devices or reinforcing trees by suitable short lengths of wire to firmly bind the new masonry or concrete I3 to the old masonry or concrete I2. When the crossarms Il and 24 are not welded in the apertures of the loopr Il they may be held in place in any other suitable manner as by passing the wire 35 around the vertical angles formed by their intersection. The reinforcing trees, while affording a strong connection between the old masonry I2 and new masonry I3, do not interfere with the filling of the cavity 25 and afforded ample space for the cement to enter all the interstices of the old concrete. l
After the reinforcing network I0 has been tensioned between the anchoring devices, the remainder of the cavity is filled with concrete so that the reinforcing network and anchors are embedded therein. However, if the patch or area to be reconstructed is of such a nature `that the concrete may be readily applied through the reinforcing latticework and around the reinforcing and anchoring trees, the filling of the cavity with concrete may be done in one operation after all the reinforcing elements have been placed in position,'instead of applying it in two operations as mentioned above. Also, in patches of the type where there are relatively few or no deep porf tions, so that relatively few, if any, reinforcing trees are used, and the tensioned network I0 is employed to furnish substantially the entire reinforcement for the concrete, the concrete may be applied in one operation.
The present invention provides a method for reinforcing replacement concrete to be used in repairing masonry whichl distributes tensile stresses such as may be induced by temperature changes across substantially the entire patch, which tensile stresses may be taken .up by the re- `ama-iso l inforcing network and the old masonry structure. Also, the installation of the reinforcing wire network with an original tensile stress enables it to function from the time of its installation, and it is unnecessary for the concrete to -be first subjected to excessive stresses before the reinforcing network will function. Furthermore, reinforcing trees have been provided which are complete" 'units individually and serve to firmly bond the new masonry to the old. l
The method which has been shown and de4v scribed is capable of numerous modifications in A order to carry out the invention in connection with the reinforcing of concrete or other masonry in various tnies of replacement work.
Although I have shown and described but a single application of my invention in reinforcing a concrete patch, it isV to be understood that many modincations are within the scope of the invention and intended to be included in the` following claims.
What claim is: l A l. The method of reconstructing concrete, comprising the steps of preparing the old concrete,
marginal portion of the region to be patched, af-
ilxing to the old concrete a plurality of anchoring means within said marginal portion for retaining a reinforcing network, securing a reinforcing network to the anchoring means below and adjacent to the normal surface of the concrete structure, and tensioning the reinforcing network throughout the region to be patched.
3. The method of reconstructing concrete comprising, vremoving the disintegrated portions of the old structure within the area to be reconstructed, aillxing a plurality of independent concrete anchoring means within the deeper por-l tions of said area, tensioning on additional anchoring -means within said area a reinforcing network over the area adjacent but below the normal surface of the concrete being reconstructed and applying the new concrete.
4. The method of reconstructing concrete comprising the steps of removing the disintegrated -portions of the old structure within the area to be reconstructed, aiflxing a plurality of independent concrete anchoring means within the deeper portions of said area, applying new concrete to the deeper portions, tensioning a reinforcing network over the area below the normal surface of the concrete being reconstructed, and applying the remainder of the new concrete.
5. The method of reconstructing concrete comy prising the steps of removing the disintegrated 6. The method of reconstructing concrete comprising the steps of removing disintegrated portions of the old structure, afxing a plurality of independent concrete supporting anchors within the area to be reconstructed, and tensioning anchors adjacent the marginal portions of. said area, applying the portion of the new concrete to the deeper portions, stretching and tensioning a reinforcing network between the tensioning anchors and applyingl the remainder of the new concrete.
l 7. A reinforced concrete patch which comprises tensioning and anchoring means aiiixed to the old structure adjacent the periphery of the area to be reconstructed, a reinforcing network stretched between the anchoring means, said network positionedsubstantially close to the surface of the replacement masonry, and elements of the network extending directly between the anchoring means whereby said elements are tensioned to transmit stresses directly to the old structure, said anchoring means having their axes at an angle less than a right angle to the direction of the stress induced by the reinforcing network, and secondary anchoring means securing the reinforcing network at spaced intervals to the old structure, said secondary anchoring means positioned in the deeper portions o f the cavity being repaired.
8. The method of reconstructing old concrete structures having Ideep and shallow portions to be filled in, comprising the steps of removing disintegrated portions of the old structure, aiilxing a plurality of concrete holding means in the solid portions of the old structure to reinforce the new concrete to be applied in the deeper portions,
securing tensioning anchors around the marginal portion of the area to be reconstructed, applying a portion of the new concrete to said deeper portions, positioning and tensioning a reinforcing network between said tensioning anchors, and securing the network to said concrete holding means, and applying the remainder of the new concrete.
9. A reinforced concrete patch, comprising a plurality of anchoring means having portions network tensioned between the anchoring means and positioned near the surface of the replacement concrete, said network having elements extending directly between said anchoring means, and concrete embedding the reinforcing network.
10. A reinforced concrete patch, comprising a plurality of anchoring means having portions thereof embedded in the old concrete a substantial distance beneath the surface thereof, said anchoring means being disposed in the old con'- crete adjacent the marginal portions of the patch, and having portions for securing a reinforcing network thereto disposed near the surface of the replacement concrete, a reinforcing network tensioned between the anchoring means and positioned near the surface of the replacement concrete, said network having elements extending directly between said anchoring means, concrete embedding the reinforcing network, and secondary anchoring means, substantially longer than the first mentioned anchoring means, disposed in the deep portions of the patch and provided with crossheads to reinforce and hold the replacement concrete in the deeper portions of the patch.
11. A reinforced concrete patch, comprising a plurality of anchoring means having portions thereof embedded in the old concrete a substantial distance beneath the surface thereof, said anchoring means being disposed in the old concrete adjacent the marginal portions of the patch, and having portions for securing a reinforcing network thereto disposed near the surface of the replacement concrete, a reinforcing network tensioned between the anchoring means and positioned near the surface of the replacement concrete, said network having elements extending directly between said anchoring means. concrete embedding the reinforcing network, and secondary anchoring means, substantially longer than the first mentioned anchoring means, disposed in the deep portions of the patch and provided with crossheads to reinforce and hold the Vreplacement concrete in the deeper portions of the patch, and means to secure said tensioned reinforcing network to said secondary anchoring means to assist in holding the network against displacement.
12. A reconstructed concrete area having marginal portions and deeper portions, comprising substantially rigid reinforcing means in the deeper portions of the area, anchored to the old concrete, a. reinforcing network disposed below, but adjacent the normal surface of the concrete being reconstructed, secured to and tensioned between a plurality of anchoring means embedded in the old concrete around the marginal portions of said area, said network having elements thereof extending directly between the last mentioned anchoring means, and concrete embedding all of said reinforcements.
Lome s. wnn'rz.`