US1993294A

US1993294A - Protective slab for concrete bodies

Info

Publication number: US1993294A
Application number: US667251A
Authority: US
Inventors: John W B Blackman
Original assignee: Individual
Current assignee: Individual
Priority date: 1933-04-21
Filing date: 1933-04-21
Publication date: 1935-03-05
Anticipated expiration: 1952-03-05

Description

Mgrch 5, 1935. J. w. B. BLACKMAN PROTECTIVE SLAB FOR CONCRETE BODIES 2 sheets-Sheet 1 Filed April 21, 193s u Znvelzfor.

Jah/u H B. Blackman/ fr/76g March 5, 1935. J. w. B. BLACKMAN 1,993,294

PROTECTIVE SLA FOR CONCRETE BODIES Filed April 21, 1953 2 Sheets-Sheet 2 36 j? Dner/afar; Jo/lm W Eff/mim an/ Patented Mar. 5f, 1935 v i UNITED STATES PATENT OFFICE i2 PROTECTIVE SLAB FOR CONCRETE BODIES John W. B. Blackman, Long Beach, Calif. Application April 21, 19323, Serial No. 667,251

16 Claims. (Cl. 726-18) This invention relates generally to protected provide for the formation o'fjoin'ts between slabs concretestructures in which concrete Walls, dams, arranged at special angles. floors, concrete piling and the like, are rendered The above mentioned and additional objects .of immune to the deleterious actionof such agencies the invention, as well as the features and details 5 as sea water, acids and alkalies, and also the eiect of certain typical and preferred embodiments 5,

of frost in rupturing the concrete where'water is thereof, will be understood most readily without allowed to penetrate the pores, by the application need for further preliminary discussion, from the to such structures of preformed slag members following description. Throughout the descripimpregnated with waterproofing material and tion reference is made to the accompanying l connected by waterproof joints. In its more drawings, in whlchz, f l 10 specific aspects, the invention deals in improve- Fig. lis a side view cfa typical, preferred form ments. upon the types of slabs and joints comofzslab embodying the invention; prising the subject matter of my copending ap- Fig. 2 is a section on line 2--2 of Fig. 1;' plication on Protected concrete structures, Ser. Fig. 3 is a fragmentary enlarged section on line l5 No. 587,702, filed Jan. 20, 1932, now issued as 3a3 of Fig. 1; 154,

Patent No. 1,953,920, dated April ,10, 1934. Fig. 4 is a viewsimilar to Fig. 3, showingV a 'I'heprincipal objects of the invention are divariational form `of the invention; rected to improvements in slabs' of the character Fig. 5 is a sectional view showing a series of stated, whereby more secure bonds .with the body the slabs applied toa concrete body, and. illusof concrete to which they are applied, may be had trating the joint formation between adjacent 20 without lessening the strength and reifectiveness slabs;

l of the joints between the slabs. The Ainvention Fig. 6 is a view similarv to Fig. 5, taken onl line may be characterized as animprovement upon 6-6 of the latter; 1 slabs 'having undercut or dovetailed recesses for Fig- 'l is a sectional view showing an arrange-j bonding to .the body of the structure to which ment of slabs at special anglesfor lining sewers,;25

the slabs are applied. Heretoiore, it has been tunnels-and the like; and y customary to extend `key recesses continuously Fig 8 is a fragmentary section on line 8--8xof through the slab, with the result that the thick- Fig. 7. l Y l l ness of theportions of the slab at the ends where Referringfflrst to Figs. v1 and 2, my preferredv S0 the key way opens, are so reduced that it becomes form of slab, generally indicated at l0,v is shown@v 30 difiicult, and in some cases impossible, to .obtain to be substantially rectangular in shape, and tto an effective joint between such end portions of have plane surfaces 11 and 12, between which the slabs. This is due to fact that a satisfactory. the slab is of substantially uniform thickness. It joint must be of greater depth than the remainwill be understood that the invention in its broad S5 ing thickness of the slabat its ends, `after the aspects is by no means-limited to slabs having 35-4 key way has been cut clear through. Although it the particular shape or dimensional characterwould be possible even under such circumstances, istics of the illustrated forms, though for, most to increase the depth of the joint by making the purposes, these shapes may belused to best adslab of greater thickness, this would be impractivantage.

40 cal in the majority of cases because of the result- Being designed to protect concrete bodiesA 40 ant increase in bulkand weight of the slabs and against dBStTuOtiVe. aCGiOn OfaCdS, alkaliea sea v material required for their formation. Water, andthe like, and toalord such protection In accordance with the invention, I have vbeen by reason 0f tS being impregnated with substance able to obtain both the advantages of akey recess resistant t0 Such agencies, `the slabs are made of in the slabs and a full joint thickness at its ends, material having Such porosity as t0 permit their 45 byconflning the key recess exclusively within the impregnation to a substantial depth. Ordinarily, slabs. In this manner, the slabs may be. formed the slabs will be made of porous concrete, although of minimum thickness and joined together with other material, such as a specially prepared 'por-` equal etfectiveness on all sides. I am also able ous clay, of suillcient porosity for impregnation to form the slabs with plane surfaces so as to and of required strength, may be used if desired/50 present, when applied to the concrete body, a' 'Ihechar'acteristics of the concrete from which smooth regular surface. the slabs are molded, and the methods enmloyedv OtherV objects have to do with novel developin forming them comprise no part of the present ments in Shaping the slabs at theirV edges to invention, but'I may mention that thse features facilitate-the forming of normal joints, and to are fully set out in my copendingapplications on 55..,

Impregnated slabs and method forming same, Ser. No. 668,379, lled April 28, 1933, and Forms for molding slab members, Ser. No. 667,252, iiled on even date herewith. Likewise, the methods which may be employed for the purpose of impregnating the slabs with waterproong material, constitute no part of this invention, and any suitable process of impregnation may be used, such as those now in commercial use. As typical of processes that have been found to be successful for thepurpose of impregnating con# crete or like bodies, I may cite the processes described in Letters Patents No. 1,555,208 and No. 1,555,209, both granted Sept. 29, 1925 to Frank S. Honberger. By the methodsdisclosed in these patents, it is possible to so thoroughly impreg nate concrete and other porous bodies with asimpregnated body will be rendered substantially immune to the deleterious action of the agencies hereinabovementioned.. y

The slab 10 is shown to be formed'with' a tongue 13 projecting from one side and end thereof, andcomplementary rgrooves 14 formed in the other side and end. Broadly speaking, the edges of the slab. may, ofzcourse, be shaped to provide any othersuitable joint connections between adjacent members.. 'A key recess, generally indicated at 16, is formed in one of the slab faces, the sides and ends'of the recess terminating within the slab, as indicated. While the key recess may be of any suitable shape, it preferably is substantially rectangular. Opposite sides of this recess are undercutas shown in Fig. 2 at 17, the purpose of the undercut being to afford a secure joint between the slab anda body of-concrete poured against it and into the recess, asI

shown in Fig. 5. i

- In Figs. 3 and 6, the ends 18 of the key recess Iare shown to slope inwardly Atoward the base 19 of the recess, the reason for so sloping the shoul-` ders at 18, being to allow' complete drainage of asphalt fromv the recess at the 'conclusion of the impregnating process.' In accordancewith'my present practice, I stand the slabs on end in a bath of the waterproofing substance, in the op'eration of impregnating. After impregnation has become complete, the slabs are removed from the bath, whereupon any of the hot waterproong material in recess 16,' will drain therefrom completely, as permitted by the outward slope Vof undercut, as well asthe sides 17, as I have indi` cated in Fig. 4 wherein the ends 18a. are shown tol `be dove-tailedin a manner similar` to the sides.

It will be. noted that beyond the ends of the keyrecess 16, the slab has the same full thickness as it has at the sides of the recess, and that the ,i joint thickness at the ends vof the slab corresponds to the thickness at its sides. As I have previously mentioned, while undercut key ways have been heretofore formed in slab members of this general character, it has been the practice to extend thev key way entirely through the slab so that the way opens at the ends` of the slab. A s a result, it has been impossible to secure the same effective joints between the ends of theslabsas at their sides, since the joint thicknessat the ends of the key` '.ways has been reduced to a distance corresponde` ing to the thickness between the base surface 19 of the recess and the slab face 12. As will be apparent, in accordance with the invention, the joints between adjacent ends of the slabs are equal in effectiveness to the joints between side edges.

In Figs. 5 and 6, I have shown the slabs applied to a concrete body in such manner as to protect the latter from deterioration. In construction, the slabs are arranged edgeto edge in the manner illustrated, and joined together by waterproofing material 20 placed in the joint spaces between adjacent slab members. As I have stated, the slabs before being applied to the concrete body, are impregnated with waterproofing substance, typically and preferably asphalt. The joint filling material 20 is of a character such that it will not only form a bond between the material or concrete from which the slabs are formed, but also such that it will become substantially integrated with the material with which the slabs. are impregnated. f Asphalt is thepreferred joint iillingv material. Ordinarily, a low penetration asphalt willbe used, and the asphalt, after first being heated to a temperature above the melting point of the asphalt with which the slabs are impregnated, is poured into the joint space. asphalt poured into. the joint melts theimpregnating asphalt at the joint surfaces, causing both,

asphalts to ow together to the extent that the joint filling asphalt, when cooled and hardened, will have become integrated or .made continuous with the impregnating asphalt, in addition to having bonded or adhered to the concrete of the slabs.

After the slabs havebeen thus joined, the concrete is poured against them, `llirig the key recesses 16 as indicated. Having rst been assembled or erected .prior to pouring the concrete, the slabs serve, in one aspect, asa permanent form for the concrete. By virtue of the imperviousness of the slabs and joints, and the immunity of the impregnating and joint lling substance to attack by the common agencies responsible for deterioration of concrete, the body of concrete 21 is fully protected from the destructive effect of fluids to which the slabs may be exposed.

In view of the desirability that the joint between the ends of the slab correspond in thickness to the joint between the side edges, it will be seen that the joint structure has a deiinite relation to the form of key recess WhichI have illustrated. The desired efficiency of thejoint as tostrength and waterproofness, is largely dee. pendent upon the full joint thickness which has been attained by discontinuing the key recess as into the top edge groove, ofi the lower slab and then placing the upper slab in position, the waterproofing material running freely throughout the full length'of the joint.: -For horizontal joints,

the`tongues.13 and groove 14 preferably have' the relative shapes indicated. i l

inasmuch as both slabs must be placed in position before the vertical joints can be poured, and

since these joints may be of such length that' Where the jointspace is restricted, the waterproofing material after being poured into the top of the joint may vcool before reaching' the bottom'thereof, it sometimes becomes desirable to increase the'cross sectional area of the vertical.

action of iiiuids which the tunnel may carryiun' joint spaces. Accordingly, as indicated. in Fig. 6, I provide for increased space iat .26 in thervertical joints, by beveling the face 13a of thetongue 13, the clearance at 27, however, preferably re'- rnaining substantially the same as inthe corre-1 sponding part of the Vhorizontally.running joints.l

Sharp `corners andv edges .onthe 'tongue and groove parts of the slab which might Yresult shapes to enable their arrangementvat special angles as required'for 4tunnel lining.'r In forming the tunnel, the concrete 30 at the bottom is iirst poured, and the floor slabs 31 placedon thewet concrete. Slabs 31 may be provided with semicircular grooves 32 for the purpose of bonding to the concrete 30, and adjacent ends 'of the slabs may be beveled asvindicated, to form a downwardly tapering opening at 33 into which waterproofing material may be poured. At the time slabs 3l are laid, lower side slabs 34 may also be laid on the fresh concretek 3Q, these slabs alsov having the bonding grooves 32, but having special shapes at their upper and lower Aedges to form special joints with thefloor slabs 31 and the ver.

tically positioned side slabs 35. The latter is shaped in accordance with the lpreviously described slab illustrated in Fig. l. The lower edge 34a of slab 34 is beveled as indicated, to form, with the adjacent edge of slab 3l, a downwardly tapering space to receive the joint iilling material; "I'he upper edge of slab 34 is beveledat an angle with the faces of the slab, and has formed therein a groove 34h to receive tongue 13 on the lower edge of slab 35, and the outer face of slab 34 is beveled at 34e to aline with the outer face of slab 35.

The upper inclined slab 36 is shaped generally similar to slab 34, being provided, however, with.

a key type recess 37, instead of semi-circular grooves, and having atits lower edge a tongue 36a projecting into the groove inthe upper edge of slab 35. The roof'iof the tunnel is lined with slabs 39 having dovetailed key recesses 40, and beveled ends forming kdownwardly tapering joint spaces at 4l. VSimilarly shaped joint spaces arer formed at 42between the edges'of slabs 36 and 39.1

As previously mentioned,

slabs

31 and 34 are rst laid upon the fresh concrete 30 in the bottom of the tunnel. Thereafter

slabs

35, 36 and 39 are arranged in the positionsy illustrated by supwhereas the corresponding joints between

slabs

31, 34, 36 and 39 will be substantially as indicated in Fig. 8, the lateral edges of the slabs being beveled to form spaces 46 into which the joint material may be poured from above.

After the joint material has hardened, concrete is then poured against the outer faces of

slabs

35, 36 and 39, as illustrated, the concrete filling the key recesses so that after the concrete has set and the forms are removed, the slabs will be securely held in place. By reason of the slabs being thoroughly impregnated and the joints filled with waterproong material, the tunnel or conduit is given a lining affording the concrete complete protection against the deleterious der conditions of use.v

I claim 1. A slab member of the character described, having formed in `one of its faces a key recess,.` the sides and endsof which terminate withinsaid slab, opposite sides of lsaid recess being undercut to form a key for bondingto` material poured intothe recess and one end of said recessbeing bev-.f eled inwardly toward the base 'thereof at an angleA opposite the angularity of the undercut at. the.

sides of the recess.

2. A slab :member of the character described, having formed in one of its faces a key recess;l the sides and ends of whichterminate'within said slab, opposite sides of said recess being undercut: to form a key for bonding to material poured into the recess, and the ends of said recess being beveled inwardly towardV the base thereofv zat Sani` angle opposite the angularity of the undercut aty the sides of the recess. f

3. A slab member of the character described, havingformed in one of its faces a key recess,

the sides and ends of which terminate within said slab, opposite sides of Ysaid recess being undercut to form a key for bonding to material poured into the recess, tongues'projecting fromone side and end of the slab, and grooves formedin the other side and end thereof, the thickness of the sides and ends ofthe slab adjacent said tonguesand grooves being substantially uniform. y Y

4. A slab member vof the character described,

having formed in one oi its faces a key recess,-

stantially the iull maximum thickness of the slab.V

5. A slab member of the character described,

formed of concrete impregnated with asphalt and: havingiormed in one of its faces a keyrecess,"

the'sides and ends of which terminate within said slab, opposite sides of said recess being'undercutl to form a key for bonding to material pouredi into the recess, and joint forming means on' the side and end edges of the slab, the sides and ends of the slab adjacent said joint forming means being of substantially uniform thickness.

.6. A slab member of the character described y having substantially plane surfaces and being of substantially uniform thickness between said surfaces,'there being formed in one of said surfacesy arectangular` key recess, the sides and ends'of which" terminate within the slab, opposite sides of.said recess being undercut toform 'a key 'for' bonding tomaterial poured into the recess and one end of saidrecess being beveledinwardly to' Ward the base thereof, tongues projecting `from poured into the recess but at least one end of the recess having no undercut, said slab member being of uniform thickness beyond the sides and ends of said recess, and joint forming means on the sides and ends of said member.

8. In structures of the character described, a

to concrete poured into the recess, the sides and.

ends of one of said members having tongue and Y groove joints with the sides'and ends of the other members, there being spaces between the sides and ends of said members to accommodate joint filling material, and said spaces being filled with Waterproofing substance integrated with the substance with which said members are impregcomparatively wide space between the tongue and nated, the joint thicknesses aty both the sides and ends of adjacent slab members being sub,-

stantially the maximum thickness of the slab.

9. In structures of the character described, a

j ,l plurality of slab members formed of porous ma- 20 terial impregnated with waterproofing substance, each of said members having formed in one of its faces a key recess, the sides and ends of which terminate within the members, each recess having an undercut side to form a key for bonding to concrete poured into the recess, the sides and ends of one of said members having tongue and groove joints with horizontally and vertically extending sides and ends of the other members,

p there being spaces between said members to accommodate joint filling material, and said spaces being lled with waterproofing substance integrated with the substance with which said members are impregnated, the spaces in the vertically extending joints being of larger cross sectional area than thespaces in the horizontally extending joints.

10. In structures of the character described, a pair of porous members impregnated with waterproofing material and joined together along vertically extending edges, the joint between said members comprising a groove formed in one of said members, and a tongue on the other member projecting into said groove, there being a the base of said groove and comparatively narrow spaces between the sides of the tongue and the sides of the groove, and waterproofing material filling the joint space and integrated with the material with which said members are im:-

pregnated.

11. In structures of the character described, a pair of porous members impregnated with Waterproofing material and joined together along vertically extending edges, the joint between said members comprising a groove formed in one of said members, and a tongue on the other member projecting into said groove, the vertically extending tongues on said slabs having beveled ends, and waterproofing material filling the joint space and integrated with the material with which said members are impregnated.

12. A slab member of the character described, having formed in one of its faces a key recess, the sides and ends of which terminate within said slab, opposite sides of said recess being undercut to form a key for bonding to material poured into the recess, one peripheral edge of said slab being beveled at an angle with the faces thereof.

13. A slab member of the character described, having formed in one ,of its faces a key recess, the sides and ends of which terminate Within said slab, opposite sides of said recess being undercut to form a key for bonding to material poured into the recess, and a tongue projecting from one peripheral edge of said slab at an angle with the faces thereof.

14. A slab member of the character described, having formed in one of its faces a key recess, the sides and ends of which terminate within said slab, opposite sides of Ysaid recess being undercut to form a key for bonding to material poured into the recess,y one peripheral edge of said slab being beveled at an angle with the faces thereof and the opposite peripheral edge of the slab having a tongue projecting at an angle with the faces of the slab.

l5. The combination comprising, a pair of slab4 members of the character described arranged edge to edge, veach slab having formed in one of its faces a key recess, the sides and ends of which terminate within the slab, opposite sides of the recess being undercut to form a key for bonding to material poured into the recess, joint edges extending along opposite sides and ends of each slab, the thickness of both the sides and ends of each slab adjacent said edges being substantially the full maximum thickness of the slab, the adjacent edges of said slabs being shaped to form a downwardly tapering joint space, and joint forming material filling said space.

16. The combination comprising, a pair of slab lmembers formed of concrete impregnated with Waterproofing material arranged edge Vto edge, each slab having formed in one of its faces a key recess, the sides and ends of vwhich terminate within the slab, opposite sides of the recess being undercut to form a key for bonding to material poured into the recess, joint edges extending along opposite sides and ends of each slab, thev