US2331657A - Method of and apparatus for constructing tanks and the like - Google Patents

Description

O 12, 1943. J. M. CRQM, 2,331, 57

METHOD OF AND APPARATUS FOR CONSTRUCTING TANKS AND THE LIKE Filed April 14, 1942 2 Sheets-Sheet l clizza l 62 0222 a?) r v y %%3 22%8' Oct.- 12, 1943. J. M. CROM 2,331,657

METHOD OF AND APPARATUS FOR CONSTRUGTING TANKS AND THE-LIKE Filed April 14, 1942 ZSheets-Sheet 2 v aw zzzom vention.

Patented Oct. 12, 1943 UNITED STATES PATENT OFFICE METHOD OF AND APPARATUS FOR CON- STRUCTING TANKS AND THE LIKE John M. Crom, Washington, D. 0.

Application April 14, 1942, Serial No. 438,918

9 Claims.

This invention relates to. method of and apparatus for constructing tanks and the like, and more particularly concerns the formation of curved or circular concrete walls in sections about a common center. Such walls and tanks are commonly constructed as monoliths and require the erection of extensive circular forms, staging, etc. The primary object of my invention is the production of a novel method and apparatus for building such construction in sections and in a manner eliminating extensive forms, staging, etc. and the large expense incident thereto for material andlabor.

My invention contemplates the employment of segmental form supports mounted for movement to different positions about a common and centrally disposed axis and adapted to support concrete receiving form surfaces facing outwardly from the axis, these surfaces being in a common circle about the axis and providing forms for sectional parts of the wall or structure to be constructed. Desired steel reinforcement can be erected in place adjacent to the form surfaces and cementitious composition is then projected onto the surfaces to the desired depth. After the formed wall has set, the form support is moved to another position and another section of the wall is formed in like manner on a form -supported thereby, the employment of a plurality of form supports permitting the shooting of one section while the previously shot section is setting. The operation is repeatedly continued until the desired wall or like construction is completed.

Walls,'tanks and the like are usually of substantial height and ordinarily require the erection of extensive scafiold ingto accommodate the workmen and equipment. Another important feature of the invention relates to novel means in the form of a circular track disposed around the proposed wall location and adjacent to the forms and carrying one or more cars with scaffolding extending to the height of the forms.

This scaffolding provides convenient support for the workmen adjacent to the forms and the cars can be conveniently moved to accommodate the different form locations. The production of such improved and convenient apparatus which eliminates the extensive scaffolding heretofore required comprises a further object of the in- Other features of the invention relate to a novel dome-ring form on and cooperating with the main form for the production of tank walls together with a dome-ring thereon, and to means permitting the retraction of the dome-ring and main form from the set walls when it is desired to move the forms to a difierent location wherein Fig. 4 is a side elevation of the dome-ring form,

- Fig. 5 is a fragmentary front elevation thereof, Fig. 6 is a front elevation of the cars and scaffolding employed, and

' Fig. 7 is a fragmentary plan view of the centrally disposed pivot axis.

One primary use for my invention resides in the construction of pneumatically placed concrete tanks and especially such tanks covered with a pneumatically placed concrete dome supported at its periphery on a dome-ring, and in the accompanying drawings I have illustrated my invention in connection with the construction of such a tank. The apparatus which I employ is relatively simple and inexpensive and is adapted to be used repeatedly without substantial deterioration, the apparatus illustrated incorporating a form-supporting frame 10 and a form l4 constructed as a permanent part of the frame and movable therewith.

In Fig. 1 I have illustrated three segmental frames I0 anchored at their inner ends on a common vertical axis l2 and having at their outer ends outwardly facing form surfaces H in a common circle l5 disposed about the axis, the frames being relatively adjustable to different positions about the axis. The axis I2 is disposed at the center of the tank to be formed and the circle [5 is disposed at the inner cylindrical surface of the proposed tank. The frames can be of any desired construction, each frame illustrated comprising a segmental unit having horizontal members l6 converging to the axis [2 and connected at H and frame work l8 supporting a form having an outwardly facing surface M. The form is of a height corresponding to the height of the proposed tank and is supported at M3 by bracing 20 extending rearwardly from an elevated position on the form and engaging the cross piece IT. The inner ends of the members l6 are connected to plates l9 slotted at 2| to receive the axis pin l2. The segmental frame ll) serves to support the forms in the several arcuate positions about the axis l2 whereby eliminating the necessity for the extensive framework heretofore required, it being understood that the forms can be a permanent part of the frame and movable therewith to new positions after the wall projected thereonto has set.

The bottom 22 of the tank is first constructed and a vertical anchoring axis pin 12 is set therein at the central axis of the proposed tank, although it will be apparent that the invention can be practiced without employing such pin or any centrally disposed anchor. The inner ends of the frames are anchored for rotation on and about this pin and the frames can be provided with casters 24 for facilitating their movement on the base 22. When the frames are adjusted to the desired working positions they are blocked up at 26 to an elevation raising the casters off the base.

Each frame l has mounted on top horizontal surface 28 a dome-ring form 30 having a downwardly and outwardly facing contour illustrated in the drawings as comprising surfaces 34 and 36 at the bottoms and front sides of steplike elements 32, and an upwardly facing surface is provided on the frame at 28 (Fig. 4). The form 30 is braced at 38 and is slidable radially on the platform 28. In Figs. 2 and 4 the dome-ring form is illustrated as located in proper position for forming the dome-ring on the top of and in conjunction with the wall formed on the surface M. The dome ring is not required for open tanks having no cover.

The relatively tall forms l0 require scaffolding support for the workmen and the production of a movable and semi-permanent structure for this purpose comprises a further feature of the invention. To this end, I provide a track or rails 40 extending circumferentially around and adjacent to the circle 15. One or more cars 42 on this track are provided with scaffolding having platforms 44 at different convenient working elevations. Preferably I provide two or more cars and bridge the gaps therebetween at the platform levels with planking 46. The cars can be moved along the track by hand or by a small engine 48. In inclement weather the workmen are protected by a canvas or like covering 50 secured to the frame l0 and draped over posts 52 and downwardly of the car scaffolding It will be understood that one or any desired number of form segments can be employed in constructing a tank and the tank sections can be constructed in such arrangement and sequence as seems most convenient. In Fig. l I have illustrated two relatively adjacent segments 54 of the tank wall as having been formed on two of the form surfaces l4, and a third form together with the scaffolding cars are located at a relatively spaced position 56 preparatory to constructing another segment of the tank. While subsequently formed segments are being constructed, the previously formed segment or segments are setting and the frames from the latter can be moved to new positions and used to support forms for forming further segments as the setting thereof is completed, such operations being continued until the entire tank wall is completed.

In locating and preparing the form for use, it is swung about the center 12 to the desired location and then blocked up at 26, and the domering form 30 is moved outwardly to and secured in the position of Figs. 2 and 4. Reinforcement rods 58 are placed vertically and in spaced relation from the form a distance approximating the thickness of the proposed wall, and mesh 60 is secured in contact with and inwardly of the rods. The bottom ends of the rods are preferably formed into anchoring hooks 62 and the top ends are uniformly curved inwardly at 64 and secured to the top of the dome form at 66. The cementitious composition is projected onto the form, through the reinforcement and mesh, to a thickness enclosing the reinforcement and is screeded by contact of screed boards with the other surfaces of the rods. The dome-ring is formed by filling the entire form space within the reinforcement and mesh as shown in Fig. 2.

After the formed wall and dome-ring have set, the segment is moved to another position as follows. The dome-ring form 30 is first released and moved inwardly sufficiently to clear the stepped surfaces 34 and 36 from the concrete, as illustrated in broken lines in Fig. 2. The blocks 26 are then removed and the form dropped onto the casters 24. Along with this latter movement, the entire form frame II] is given a slight radial adjustment inwardly, the frames being provided with the slots 2| at the pin l2 to permit such adjustment. The frame is then free for movement on the casters 24 to the next position of use.

The reinforcement rods are tapped with a hammer sufficiently to loosen their bonding engagement with the concrete and when the entire tank wall and dome-ring have been completed and are fully set the reinforcement is placed under tension. This tensioning is effected by rotating the sleeve nuts 10 which operation also places the wall in compression. The hooked ends 62 serve to anchor the rods at their bottom ends and the top ends can be suitably anchored in the dome-ring by shooting cementitious composition into bonding engagement with such ends. I also prefer to bond in the bottom ends of the rods, as illustrated at 12, before tensioning the rods. The tank is thereafter completed by placing rod reinforcement under tension circumferentially around the tank in contact with the vertical rods 58 and then projecting on and into bonding engagement with both such rods a suitable layer of concrete, all as described in my Patent No. 2,315,894 dated April 6, 1943.

Having thus described my invention what I claim as new and desire to secure by letters Patent of the United States is:

l. A method of constructing a curved tank wall and dome-ring in sections disposed about a common center, which consists in providing a form having an outwardly facing convex surface curved about a predetermined center and a domering form at the top thereof having a downwardly and outwardly facing contour, forming a concrete wall section on said surfaces, shifting the form downwardly and inwardly toward the center sufficiently to clear the formed wall section after the concrete has set, moving the form about said center to an adjacent position and forming another cementitious wall section thereon, and continuing the operation of thus forming cementitious wall and dome-ring sections about the center until the desired wall and dome-ring is completed.

2. Apparatus for constructing a concrete tank wall and dome-ring in sections disposed about a common center, comprising a main form having a concrete-receiving surface facing outwardly from a predetermined center,-a dome-ring form on the top of the main form and having a form contour facing downwardly and outwardly, the dome-ring form being adjustable radially inward relative to the main form to clear said contour from contact with a concrete dome-ring formed thereon, and means anchoring the forms for movement about said center to different positions in which the said surface is disposed substantially within an are extending about said center.

3. Apparatus for constructing a cylindrical concrete Wall in sections, comprising a plurality of segmental frames anchored at their inner ends on a common vertical axis and having, at their outer ends outwardly facing surfaces in a common cylindrical plane disposed about the axis, the frames being relatively adjustable to different positions about the axis and said surfaces being adapted to receive wall-forming cementitious composition projected thereonto pneumatically from points spaced outwardly therefrom.

4. A method of constructing curved concrete walls, tanks and the like, on a base and in sections disposed about a common center, which consists in supporting a form having a surface extending upwardly from the base to the height of the wall to be formed and curved arcuately about and facing outwardly from a vertical axis at said center, projecting cementitious composition pneumatically against said surface from points spaced outwardly therefrom and to a" depth forming a cementitious wall thereon, thereafter moving the form support about said axis to an adjacent position and forming another cementitious wall section on a form surface supported thereon and in edge to edge abutting relation to a like wall section previously formed in like manner, and continuing the operation of thus forming cementitious wall sections until a wall of the desired dimension is completed.

5. A method of constructing concrete walls, tanks and the like in sections disposed in alignment about a common center, which consists in providing a plurality of forms each having an upright surface facing outwardly from a common center, projecting cementitious composition pneumatically onto said surfaces from points spaced outwardly therefrom to a depth forming wall sections thereon, moving one of the forms about a vertical axis at the center to another position after the cementitious wall thereon has set, projecting another wall section in like manner thereonto while the wall section previously formed on another of said surfaces is setting, and repeating the operation until the desired wall disposed about the center is formed, said surfaces being located in a common annular plane about said axis during the wall forming operations thereon.

6. A method of constructing a curved concrete wall in sections about a predetermined center,

which consists in providing a plurality of forms each having an outwardly facing convex surface curved in a common annular plane about said center and having an area which is of a height substantially equal to the wall to be formed and of a width equal to a segment thereof, projecting wall-forming cementitious composition pneumatically onto said surfaces from a support movable on a track curved about said center forwardly of and adjacent to the surfaces, moving the forms about the center to other positions after walls formed thereon have set, and continuing the operation of forming said wall sections by projecting cementitious materialfrom the track support onto the form surfaces moved about said center until the desired wall is completed.

7. Apparatus for constructing concrete walls, tanks and the like in sections disposed about a common center, comprising a segmental frame supporting thereon a form having a form surface extending upwardly from a wall-supporting base to the height of the proposed wall, said surface facing outwardly from a predetermined center and being of a width forming a segment of an annulus around said center, and means anchoring the frame for movement about said center to different positions wherein it is adapted to support a form thereon with its said surface in the annulus, said surface being adapted to receive wall-forming cementitious composition projected thereonto pneumatically from points spaced outwardly therefrom.

8. The apparatus defined in claim 7 in which the frame and form have at their top portion a dome-ring forming contour with an upwardly facing concrete-receiving surface, and means' whereby the frame and form can be slightly. dropped and shifted radially toward said center to clear a concrete dome-ring and wall section formed on said upwardly and outwardly facing surfaces.

9. Apparatus for constructing relatively high vertical walls for tanks and the like in sections about a common center, comprising a relatively tall and segmental form having a concretereceiving surface facing outwardly from a predetermined vertical axis, a frame having a vertical portionsupporting the form thereon and a substantially horizontal portion extending to and anchoring the frame for adjustment to different positions about said axis as a center, and bracing extending rearwardly and'downwardly from the vertical portion of the frame to the horizontal portion, the frame being adjustable horizontally to different positions about the axis as a center.

JOHN M. CROM.

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