US3596417A

US3596417A - Precast rooms

Info

Publication number: US3596417A
Application number: US814612A
Authority: US
Inventors: Henry B Zachry
Original assignee: H B ZACHRY Co
Current assignee: H B ZACHRY Co
Priority date: 1969-04-09
Filing date: 1969-04-09
Publication date: 1971-08-03
Anticipated expiration: 1988-08-03

Abstract

Concrete rooms, each having an integrally cast top segment, consisting of a top panel and three sidewalls, and a precast floor segment, secured to the top segment during its integral casting, are stacked on top of one another to form a rigid structure of multiple floors. The rear ends of the rooms have integrally cast cantilevered overhangs such that when the rear ends of two stacks of rooms are positioned adjacent one another the cantilevered overhangs form floors and ceilings for the corridors defined by the space between the stacks. Each stack of rooms consists of an alternating arrangement of long and short rooms, each short room having a locking ridge at its forward end for locking into an opening formed across the forward end of a corresponding longer room.

Description

United States Patent [72] Inventor Henry B. Zachry San Antonio, Tex. [21] Appl. No. 814,612 [22] Filed Apr.9, 1969 [45] Patented Aug.3, 1971 [73] Assignee 11.13. Zachry Company San Antonio, Tex.

(54] PRECAST ROOMS 6Claims,2Drawlng Figs.

[52] U.S.C1 52/73, 52/79, 52/122, 52/236 [51} 1nt.Cl E0412 1/34, E04h H04 [50] Fieldoi'Search 52/79, 73, 234, 236, 237; 46/25, 19

[56] References Cited UNITED STATES PATENTS 2,691,291 10/1954 Henderson 52/79X 3,292,327 12/1966 Van Der Lely.. 52/79 3,446,340 5/1969 Mullen 52/403 1,362,069 12/1920 Witzel 52/745 3,162,863 12/1964 Wokas 52/79 3,468,081 9/1969 Saarinen 52/79 FOREIGN PATENTS 1,202,413 1959 France 52/79 1,465,539 1966 France 52/236 766,840 1967 Canada 52/79 Primary Examiner-John E. Murtagh Attorney-Christie, Parker & Hale ABSTRACT: Concrete rooms, each having an integrally cast top segment, consisting of a top panel and three sidewalls, and a precast floor segment, secured to the top segment during its integral casting, are stacked on top of one another to form a rigid structure of multiple floors. The rear ends of the rooms have integrally cast cantilevered overhangs such that when the rear ends of two stacks of rooms are positioned adjacent one another the cantilevered overhangs form floors and ceilings for the corridors defined by the space between the stacks. Each stack of rooms consists of an alternating arrangement of long and short rooms, each short room having a locking ridge at its forward end for locking into an opening formed across the forward end of a corresponding longer room.

PATENTED AUG 31971 INVEN'IOR. HENRY B. z/vc m PRECAST ROOMS BACKGROUND OF THE INVENTION This invention relates to building construction, and more particularly to precast concrete rooms which are stacked on top of one another to form a rigid structure.

System-building techniques, in which prefabricated structural units are assembled to form a building, are of major consequence in the construction industry. Precast concrete modules, used in the construction of hotels, office buildings, and the like, are especially well suited for this type of construction. The precast units are fabricated at a casting plant adjacent the construction site or at a distance therefrom. They are then lifted by cranes into position on top of one another and secured together to form a rigid structure.

At present, it is often required that a frame be provided for supporting the concrete modules and for aligning them with respect to one another. Attempts to eliminate frames have generally been unsuccessful. For example, it has not been possible to accurately align a number of modules in the required configuration. Fastening of the modules to one another, using tie rods and the like, has also been less than satisfactory and ordinarily has resulted in increased construction costs.

STATEMENT OF THE INVENTION This invention relates to a structural system in which a number of precast concrete rooms, having load bearing walls, are stacked together to form a rigid structure. Each of the rooms has an integrally formed top segment comprising a ceiling and sidewalls, with one side of the room being completely open. A precast concrete floor is secured to the top segment during integral casting thereof. The end of a unit opposite its open end has a cantilevered overhang which serves as a portion of a corridor adjoining such end, a corresponding overhang of a second unit serving as the remaining portion of the corridor. The concrete room is precast to form an integral unit by an initial casting operation to form the floor and a subsequent casting operation wherein the ceiling and three sidewalls are simultaneously cured and secured to the floor.

In the preferred form of the invention, the room is reinforced by a number of steel-reinforcing bars embedded in the concrete structure and extending across the walls, floor and ceiling. Steel rods or cables can be employed to prestress the concrete in three directions. The sidewalls may have any number of openings cast in them for doors, windows, plumbing, air-conditioning ducts, and the like. For example, the open wall of the unit, ordinarily disposed at the outside surface of the structure, can be relatively large for accommodating sliding glass doors. Lifting loops project from the ceiling of the unit, the loops being formed by the projecting portions of steel cables embedded in the concrete.

The structural system preferably comprises the stacking of alternate long and short room units. Each of the short units has a locking ridge at its forward end. Each long unit has an opening adjacent its forward end for receiving the locking ridge of a short unit placed on top thereof. The cantilevered overhang of each unit projects above the surface of the top panel. A short unit can thereby be positioned on top of a long unit so that its rear end abuts the raised portion of the long unit's cantilevered overhang and so that its forward end locks in the opening of the long unit. As a result, the units can be stacked on top of one another without the need for a frame or supporting network.

The cantilevered overhangs of the precast units preferably have a number of reinforcement rods embedded in the concrete and projecting outwardly. When adjacent rear ends of two units are aligned, the reinforcement rods overlap and are welded together. The openings between the overhangs are filled with concrete, which is cast to complete formation of the corridor. The completed closure thus defines both a floor for the corridor above the aligned units and a ceiling for the corridor between such units.

FIG. I is a perspective view ofa precast concrete unit ofthis invention; and

FIG. 2 is an elevation view of the precast concrete units.

l, structural system using DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. l, a room 10 includes a rectangular,

horizontal top panel or ceiling 12 formed of concrete and cast integrally with two elongated sidewalls M and a single, shorter end wall 16. A conventional door opening (not shown) is formed in the end wall, the open side of the room opposite thereto having a sliding glass door 18. Other openings (not shown) such as bathroom exhaust, windows, and air-conditioning ducts, may also be provided.

A plurality of reinforcing bars or cables 20 are disposed in the top, floor and walls of the room. Steel cables 22 are embedded in the walls of the unit with their looped ends 24 projecting from the ceiling portion thereof, the loops serving as hoist connections for permitting the units to be hoisted by a crane.

The rear end of the concrete unit, to be disposed toward the inside of the building under construction, has a cantilevered overhang 26 projecting from its upper edge. The overhang is integrally cast with the ceiling and three walls. Steel-reinforcing rods 28 are embedded in the overhang and project therefrom along its three sides.

The forward end of the precast unit has a raised panel section 30 behind which is disposed an opening 32 in the roof of the unit. The opening is used to lock a shorter precast unit on top of the illustrated room, the top unit fitting between the side 34 of the raised panel and the side 36 of the projecting overhang 26. The open side of the front end of the precast unit is preferably closed by slidable glass windows 38 and the door l8, which are disposed between the floor 40 and ceiling 12 adjacent the opening 32 in the roof. A railing 42 is disposed across the width of the opening adjacent the ends of the sidewalls, defining a balcony area between the railing and the glass partition.

A number of horizontally extending steel rods 44 project from the sidewalls of the unit adjacent the opening of the roof, the steel rods securing on either side of the unit a steel plate 46. The steel plate and rods can be aligned with similar plates and rods on units spaced adjacent and on top of or below the illustrated unit.

FIG. 2 shows a rigid structure constructed in accordance with the structural system of this invention. A long unit 48, supported on a base 50, forms the first flloor of the structure. A short unit 52 is disposed on top of the long unit between the raised edge 36 of the cantilevered overhang and the rear edge 34 of the raised panel 30 of the long unit. The short unit has a locking ridge 54, partially shown in dotted lines, which projects into the opening 32 of the long unit, such that the upper unit is securely mounted on the lower unit. Adjacent steel plates 46 secured to the upper and lower units are welded together at their contacting edges 56 to further secure the units. The rooms can be tied together by weldments or resin systems and by prestressing of the walls, floors and roofs in three directions, using rods or cables. Neoprene pads or other flexible material 58 can be disposed between the rooms to obtain precise leveling of the stacks. A second stack of precast units (not shown) can be positioned adjacent the stacks shown in FIG. 2 and secured at its forward end thereto by welding together of the steel reinforcing rods 44 projecting from the side plates 46. Brick-faced concrete closure panels (not shown) which cover the space separating adjacent units, are then secured to the reinforcement rods and steel plates of each adjoining unit to complete the outward side of the structure. Removable closure panels (not shown) are disposed at the inner ends of the units. An integral cover or slab 60 can be disposed across the tops of the adjacent stacks to complete the structure. Alternately, such integral cover or slab can be used as a floor for a precast unit or the like having a larger surface area than that of the units stacked below it.

The cantilevered overhangs 26 of two

bottom units

47,48 are finished to provide a ceiling 62 for the hallway between the lower units and a floor 64 for the hallway running between the

upper units

51,52. The steel-reinforcing cables 28 projecting from each overhang are welded together and concrete is cast in such spaces using box forms.

In construction of a building using a structural system as in accordance with this invention, a number of concrete modules are cast at a casting plant either adjacent the construction site or at a distance therefrom. lf cast at a distant plant, the modules can be easily moved by truck or the like to the construction site. Each unit is completely finished prior to its assembly in the structure. For example, heating and air-conditioning units, carpeting, electrical connections, and the like, are installed at the casting plant area. All furnishings going into the rooms are likewise placed in the rooms before their movement from the casting yard.

The precast units are readily lifted into position using a large crane having a hoisting platform for attachment to the four lifting loops of the unit. Before placing one unit in posi tion on top of another unit, leveling pads of resinous grout or the like are spread on top of the room on which the unit is to be placed. The pads, typically of about ifi-inch thickness, are set to establish grade so that each room can be leveled and plumbed with elimination of any cumulative error. The resinous grout ordinarily develops a strength of about 4,000 p.s.i. in from 30 minutes to about 2 hours. Prior to positioning of the room on the leveling pads, a cement-sand grout layer, slightly thicker than a leveling pad, is placed around the top perimeter of the bottom room unit. The next unit is thus positioned in full contact with the lower unit, resting firmly on the leveling pads and grout bed.

In a preferred technique for erecting a building, using precast concrete modules substantially the same as those described in FIGS. 1 and 2, a stack of modules is formed by alternating long and short units, each pair of long and short units being locked together by a ridge of a short unit and an opening of a long unit. That is, after proper positioning of a long unit, a short unit is lifted into position with its rear end abutting the projecting edge of the cantilevered overhang of the long unit and with the projecting ridge of the short unit's opposite end locking with the opening formed in the long unit. A similar stack of alternating long and short units is aligned with the first stack with their rear ends positioned so as to form a corridor between the end walls. A pair of such stacks can then be positioned adjacent the first pair of stacks.

Preferably, the adjacent stacks are assembled so as to alternate long and short units across the face of the structure as well as vertical thereto. That is, when three stacks of modules are positioned adjacent one another, each unit of one length will have units of the opposite length adjacent each of its opposing sidewalls. The resulting structural system thereby can be rapidly constructed and is characterized by overall rigidity.

lclaim:

l. A structural system comprising aplurality of precast concrete rooms stacked together to'form a rigid structure each room having a top panel integrally formed with three sidewalls, at least one of the sidewalls having an opening, and a floor secured to the sidewalls, the floor being precast. and secured to the walls simultaneously with integral casting ofthe walls, the stacked rooms defining pairs of interlocking concrete rooms of long and short lengths, the lower room being longer than the upper room and having an opening adjacent its forward end, the upper room having a projecting ridge along its lower front edge, the ridge being adaptable for interlocking with the opening of the lower room.

2. The structural system of claim 1 wherein the building has both rows and columns of alternating long and short rooms.

3. The structural system of claim 1 wherein each room has a vertically disposed steel plate and horizontally projecting reinforcement rods secured to the forward edge of each sidewall, such that an interlocking pair of units can be positioned to align the steel plates so that they can be welded together to securely cou le each pair of units, the reinforcement rods being ahgna le with the reinforcement rods of ad acent modules so that they can be welded together to secure adjacent stacks of units.

4. A building comprising a plurality of precast concrete rooms stacked together, each room including a floor, at least three load-bearing sidewalls integral with the floor, and a top panel integral with the sidewalls, each pair of stacked rooms having a cooperating floor and top panel defining an interlocking interface with a projecting ridge integral with one room constructed to interlock with an opening in the other room so the two rooms form a rigid structure; and a vertically disposed steel plate abutting a sidewall of each room, and horizontally projecting reinforcement rods embedded in each sidewall, the steel plates being aligned when the rooms are stacked together so that the plates can be welded together to securely couple the rooms, with the reinforcement rods of each room being arranged to align with the reinforcement rods of an adjacent room so the rods can be welded together to secure adjacent stacks of rooms.

5. A building according to claim 4 wherein each room has a cantilevered overhang integral with an edge of its respective top panel, each overhang including means for joining it with another room disposed adjacent to it to form a corridor between the adjacent rooms.

6. A building according to claim 4 wherein each interlocking pair of stacked rooms defines a lower room and an upper room; and wherein the ridge is integral with the bottom surface of the floor of the upper room so as to project downwardly toward the lower room, and the opening is formed in the top panel of the lower room so that the ridge interlocks with the opening when the upper and lower rooms are stacked.

Claims

1. A structural system comprising a plurality of precast concrete rooms stacked together to form a rigid structure each room having a top panel integrally formed with three sidewalls, at least one of the sidewalls having an opening, and a floor secured to the sidewalls, the floor being precast and secured to the walls simultaneously with integral casting of the walls, the stacked rooms defining pairs of interlocking concrete rooms of long and short lengths, the lower room being longer than the upper room and having an opening adjacent its forward end, the upper room having a projecting ridge along its lower front edge, the ridge being adaptable for interlocking with the opening of the lower room.

3. The structural system of claim 1 wherein each room has a vertically disposed steel plate and horizontally projecting reinforcement rods secured to the forward edge of each sidewall, such that an interlocking pair of units can be positioned to align the steel plates so that they can be welded together to securely couple each pair of units, the reinforcement rods being alignable with the reinforcement rods of adjacent modules so that they can be welded together to secure adjacent stacks of units.