US2509180A - Load transfer device - Google Patents

Description

y 3, 1950 R. c YEOMAN ,50 8

LOAD TRANSFER DEVICE Filed Feb. 25, 1945 2 Sheets-Sheet 1 I f I I May 23, 1950 R. c. YEOMAN 2,509,180

LOAD TRANSFER DEVICE Filed Feb. 23. 1945- 2 Sheets-Sheet 2 in proper vertical alignment and so that the edge portions of the slabs adjacent the joints will not readily break under load. Upon changes in temperature causing expansion or contraction of the slabs, the joints will tend to move together or to separate. This will cause the projecting portions l8 to slide over the bearing shoulders I without interrupting the transmission of load between the slabs. In the event the slabs should tend to separate to an undesired extent, the crossbar portions l9 engage the shoulders I! formed by the openings IE to restrict relative movement of the slabs to such an extent that the sealing material i2 would lose contact with the slab faces. This construction prevents excessive movement of the slabs which might cause the joints to open up excessively and serves to minimize dragging of any one slab an excessive amount on the subgrade in the event all of the joints should not function properly. The expansion and contraction is, therefore, distributed more or less uniformly throughout the entire structure and the expansion filler between all of the joints is maintained under corking pressure.

In the construction illustrated in Figure 4 the load transfer members include body portions 22 adapted to be anchored in the slabs in the same manner as the body portions l3 of Figures 1 to 3. Angularly projecting roughened arms 23 project from the body portions 22 to assist in anchoring them in the slabs. Each member has one face of its body portion cut away as indicated at 24 to form a recess bounded on one side by a horizontal shoulder 25 and is formed adjacent the end of the recess with a transverse opening 26 extending horizontally through the body portion.

Each member is formed with a bridging portion 21 substantially half the thickness of its body portion adapted to fit into the recess 24 on the opposite member with its upper edge resting against the shoulder 25 to transmit vertical loads between the slabs At its outer end, each of the bridging portions is formed with a laterally extending head 28 adapted to enter the opening 26 of the opposite member and to fit loosely therein.

The load transfer members of Figure 4 are adapted to be assembled in the slabs in substantially the same manner as illustrated in Figures 1 and 2 with the bridging portion 21' of each member resting against the shoulder 25 of the other member and with the head part 28 of each member fitting loosely into the opening 26 in the other member. As shown, the openings 26 are vertically elongated so that the head parts 28 can move vertically therein. This construction operates substantially like that of Figures 1 to 3, the head parts 28 moving in the openings to provide for limited horizontal movement between the slabs.

The construction of Figure 5 is similar to that of Figure 4 and includes a pair of members each having a body or anchor portion 3| adapted to be anchored in the slabs by angularly projecting arms 32 Each body is formed with relatively deep recess bounded by horizontal shoulders 33 and has a horizontal opening 34 extending partially through the body portion at the inner end of the recess Bridging portions 35 substantially half the width of the body portions project therefrom to enter the recesses in the opposite members with the upper and lower surfaces thereof slidably engaging the bearing shoulder 33 and clearing companion shoulder 33a, The outer end of each bridging portion is turned over as indicated at 36 to enter the opening 34 of the opposite member. The turned parts 36 are preferably smaller than the openings 3A to provide for limited horizontal movement. In operation, the device shown in Figure 5 functions in substantially the same manher as the device of Figures 1 to 4 to transmit vertical loads between the slabs and to limit relative horizontal movement of the slabs.

While several embodiments of the invention have been shown and described in detail, it will be understood that these are illustrative only and are not intended as a definition of the scope of the invention, reference being had for this purpose to the appended claims.

What is claimed is:

1. A load transfer device adapted to be im bedded in adjoining concrete slabs for transferring loads therebetween and for limiting separation thereof comprising a pair of identical integral members, each member including an anchor portion adapted to be imbedded in one of the slabs and a longitudinal bridging portion extending into the anchor portion of the other member and adapted to span the joint between the slabs, the anchor portion of each member being formed with a longitudinal recess longitudinally slidably to receive the longitudinal bridging portion of the other member and adapted to transfer vertical loads between the adjacent slabs and having an opening extending transversely from the recess, and a transversely projecting part on each of the bridging portions entering the opening in the other member, the longitudinal dimension of the transversely projecting parts being substantially less than the longitudinal dimension of the transversely extending openings for providing limited longitudinal relative movement of the pair of members and adapted to provide limited separation of the adjacent slabs.

2. A load transfer device adapted to be imbedded in adjoining concrete slabs for transferring loads therebetween and for limiting separation thereof comprising a pair of identical integral members, each member including an anchor portion adapted to be imbedded in one of the slabs and a longitudinal bridging portion extending into the anchor portion of the other member and adapted to span the joint between the slabs, the anchor portion of each member being formed with a longitudinal recess longitudinally slidably to receive the longitudinal bridging portion of the other member and adapted to transfer vertical loads between the adjacent slabs and having an opening extending transversely from the recess, and a transversely projecting part on each of the bridging portions entering the opening in the other member, the longitudinal dimension of the transversely projecting parts being substantially less than the longitudinal dimension of the transversely extending openings for providing limited longitudinal relative movement of the pair of members and adapted to provide limited separation of the adjacent slabs and a seal for the transversely extending openings adapted to prevent concrete from entering the same.

3. A load transfer device adapted to be imbedded in adjoining concrete slabs for transferring loads therebetween and for limiting separation thereof comprising a pair of identical integral members, each member including an anchor portion adapted to be imbedded in one of the slabs and a longitudinal bridging portion extending into the anchor portion of the other member and adapted to span the joint between the slabs, the anchor portion of each member being formed with a longitudinally arranged T-shaped recess, and a cross Dart at the end of each of the bridging portions, the bridging portion of each member longitudinally slibably fitting into the recess of the other member and adapted to transfer Vertical loads between the adjacent slabs, and the longitudinal dimensions of the cross parts being substantially less than the longitudinal dimension of the T-shaped recesses for providing limited longitudinal relative movement of the pair of members and adapted to provide for limited separation of the adjacent slabs.

4. A load transfer device adapted to be imbedded in adjoining concrete slabs for transferring loads therebetween and for limiting separation thereof comprising a pair of identical integral members, each member including an anchor portion adapted to be imbedded in one of the slabs and a longitudinal bridging portion extending into the anchor portion of the other member and adapted to span the joint between the slabs, the anchor portion of each member being formed with a longitudinal recess longitudinally slidably to receive the longitudinal bridging portion of the other member and adapted to transfer vertical loads between the adjacent slabs and having a single opening extending transversely from the recess, and a single transversely projecting part on the end of each of the bridging portions entering the opening in the other member, the longitudinal dimension of the transversely projecting parts being substantially less than the longitudinal dimension of the transversely extending openings for providing limited longitudinal relative movement of the pair of members and adapted to provide limited separation of the adjacent slabs.

5. In combination with a pair of adjoining concrete slabs, aload transfer device imbedded in the adjoining slabs and comprising a pair of identical integral members, each including an anchor portion imbedded in one of the slabs and a longitudinal bridging portion spanning the joint between the adjacent slabs and extending into the anchor portion of the other member, the anchor portion of each member being provided with a longitudinal recess longitudinally slidably to receive the longitudinally bridging portion of the other member for transferring vertical loads between the adjacent slabs and having an opening extending transversely from the recess, and a transversely extending part on each of the bridging portions entering the opening in the other member, the longitudinal dimension of the transversely projecting parts being substantially less than the longitudinal dimension of the transversely extending openings for providing limited longitudinal relative movement of the pair of members and limited longitudinal separation of the adjacent slabs.

6. In combination with a pair of adjoining concrete slabs, a load transfer device imbedded in the adjoining slabs and comprising a pair of identical integral members, each including an anchor portion imbedded in one of the slabs and a longitudinal bridging portion spanning the joint between the adjacent slabs and extending into the anchor portion of the other member, the anchor portion of each member being provided with a longitudinal recess longitudinally slidably to receive the longitudinal bridging portion of the other member for transferring vertical loads between the adjacent slabs and having an opening extending transversely from the recess, and a transversely extending part on each of the bridging portions entering the opening in the other member, the longitudinal dimension of the transversely projecting parts being substantially less than the longitudinal dimension of the transversely extending openings for providing limited longitudinal relative movement of the pair of members and limited longitudinal separation of the adjacent slabs, and a seal for the transversely extending openings for preventing concrete from entering the same.

RAY CYRUS YEOMAN.

REFERENQDES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,063,749 Parker Dec. 8, 1936 2,098,292 Jacobson Nov. 9, 1937 2,261,602 Yeoman Nov. 4, 1941 2,351,255 Fischer June 13, 1944 2,355,771 Yeoman Aug. 15, 1944 2,358,328 Heltzel Sept, 19, 1944

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