Static structures (e.g. – buildings) – With component having discrete prestressing means
Reexamination Certificate
1999-01-19
2001-06-05
Friedman, Carl D. (Department: 3635)
Static structures (e.g., buildings)
With component having discrete prestressing means
C052S089000, C052S023000, C052S745080, C052S741120
Reexamination Certificate
active
06240686
ABSTRACT:
BACKGROUND OF THE INVENTION
The impetus for mankind to create buildings is likely traceable to the original desire for more comfortable domiciles. Throughout millennia and around the world, various peoples have used indigenous materials to create shelters that resist the elements and provide warmth, space, and protection. The variety of materials used for this general purpose range widely, from bamboo poles and palm thatch to stone and adobe brick, animal skins and snow blocks, logs and oakum, lumber, concrete, steel and glass.
Despite the diversity of building material that have been used, the general approach to designing buildings has remained remarkably similar throughout the cultures and peoples of the world. Generally speaking, domiciles and other buildings are constructed of load-bearing walls that support a sheltering roof. If this concept is extended, the floor may be supported by the bearing walls to be spaced above the ground, and more than one floor may be provided in vertically spaced relationship, also supported by the load-bearing walls. Exceptions include the Inuit igloo, built of snow blocks in a dome shape, and the teepee of the plains Indians, but these structures are at or below grade level and cannot be extended upwardly.
The general approach for construction of a home or similar small building has evolved into a standard procedure. First a framework for load-bearing walls is constructed on a suitable foundation, then a framework for the floor(s) is added, as well as a framework for a roof. An exterior surface is added to the walls framework, a roof is added above, insulation is added to the walls, flooring is placed on the interior framework, and interior finish work is applied to create amenities for the interior rooms. That is, first the mechanical structure is created, and then the remaining parts of the building are hung on the structure to form the finished construction.
This approach to building tends to view each building sub-system as a separate entity with a function that is not directly related to the other sub-systems. For example, exterior siding is not considered to be a structural reinforcing element, nor is the insulation utilized in a way that would augment the load-bearing strength of the walls. In this piecemeal approach, the sub-systems are not synergistic. In addition, this standard approach to building construction requires a large amount of skilled labor from several distinct trade groups: carpenters, plasterers and sheetrock workers, and roofers. In general, the amount of skilled labor required, together with the sub-system approach to construction, has resulted in home construction and small building construction in general being expensive. These factors have priced home ownership beyond the reach of too many persons, particularly outside the developed, industrialized countries of the world.
One approach to overcoming these obstacles to inexpensive homes and buildings has been the creation of modular buildings manufactured in mass production and transported to a construction site. Generally speaking, these modular arrangements continue to rely on the traditional approach to construction, including load-bearing walls to support the floor(s) and roof, and each sub-system remains a separate entity in a functional sense. However, each module incorporates portions of each building sub-system, which are joined at the construction site to form a traditional construction. The advantage in cost is due to mass production, not to structural innovation, and there is a penalty to be paid in enforced uniformity in building design.
There have been many modern innovations in structural design and materials, but these innovations have not been widely adopted. The Quonset hut of W.W.II exploited the inherent strength of an arch to form a shelter of relatively thin sheet metal and no other supporting structure, and was cheap, portable, and easy to construct. However, the noisiness of the bare sheet metal and the lack of thermal insulation prevented its widespread use beyond temporary military buildings. Likewise, the development of tensegrity principles by Buckminster Fuller and their application to geodesic domes resulted in a few structures of renown, some military uses (radomes), and virtually no ongoing commercial success. New materials such as structural foamed plastics have been applied most notably as shear connectors in sandwich panels for aircraft wing construction, by Bert Rutan and others, and there is an active and growing interest in applications of structural insulated panels.
There remains in the prior art an unmet need for a inexpensive, practical approach to building a home or small building that is durable, comfortable and easy to construct.
SUMMARY OF THE INVENTION
The present invention generally comprises a method and structure for forming a practical, inexpensive small building for housing and other purposes. A salient aspect of the building is that the components are structurally integrated and interactive, and the structure is strong, easily built, comfortable and practical.
In one aspect, the structure of the invention comprises a continuous curved wall forming a semi-arcuate arch, and the wall is comprised of lightweight cellular material such as foamed plastic (expanded polystyrene or the like) blocks or bricks formed as curved sections of the arch. The blocks may be identical and interchangeably secured in place by adhesive or the like to form the wall, so that the arch is easily constructed. The arched wall is a convex structure defining a sheltered space thereunder, and comprises both the longitudinal sides and the top of the structure.
In addition, the structure includes an outer skin of sheet metal, tensile plastic, or the like which covers the entire convex exterior of the arched wall. The outer skin provides resistance to weather elements, and serves the purpose of a roof and wall siding. More importantly, the outer skin is anchored to the foundation of the arched wall, and is placed under tension at each anchor, whereby the outer skin applies a compressive force uniformly to the outer surface of the arched wall. The compressive force significantly augments the inherent strength of the arch, resulting in a structure that is made very strong with a minimum mass of material. Thus the compressed arched wall may support expected snow loads, as well as wind and seismic shear, ice, and the like.
The method of the invention includes the steps of providing a plurality of cellular blocks of expanded foam plastic or the like, each block defining an angular increment of an arched wall and having a length that is an incremental portion of the length of the arched wall. A foundation may be constructed; e.g., a pair of longitudinally extending footings that are laterally spaced to support the opposed lower edges of the arched wall. A course of blocks is then placed on each footing and adhered in place. Second courses of blocks are placed atop the first rows and adhered in place, and this process is reiterated, including the use of temporary bracing to support the developing arches extending upwardly and converging from each footing. This procedure is reiterated until the arched wall is completed.
Thereafter, an outer skin is formed over the exterior surface of the arched wall. The outer skin may comprise a unitary tensile sheet, or a plurality of strips of sheet metal, tensile plastic or the like, each strip having a width preferably equal to a plurality of blocks and a length equal to the peripheral extent of the arch.. The tensile sheet or strips are placed circumferentially about the arched wall, extending in a plane generally perpendicular to the axis of symmetry of the arched wall. The strips may overlap slightly and be sealed therebetween to form a waterproof assembly.
The lower ends of each strip are anchored to the respective adjacent footing, and thereafter placed under tension to draw the strip compressively about the underlying portion of the arched wall. This procedure is reiterated for all the strips, thereby placing
Friedman Carl D.
Yip Winnie
Zimmerman Harris
LandOfFree
Prestressed unitary building method and structure does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Prestressed unitary building method and structure, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Prestressed unitary building method and structure will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2486628