US 3827895 A
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MOD-WALL CONCRETE William Leo Copeland, 3405 Marks St.,
. Shreveport, La. 71103 No Drawing. Filed Mar. 27, 1972, Ser. No. 238,659
Int. Cl. C04b 7/04 US. Cl. 106-99 6 Claims BACKGROUND OF INVENTION Field of the Invention ,EI'his invention relates to a new composition for use in building structures, and more particularly, to a new composition which may be poured asa liquid and combines the features of strength, shocldresistance, insulation, and waterproofing qualities in a single material.
DESCRIPTION, OF THE PRIOR ART Conventional building techniques may be typified by the;constructionofaconventional home or office building inyvhich the following sequence is followed: The lot or -ground, areaupon which the structure is to be constructed mustiirst be graded ,and the slab poured after footings are dug and forms set. Skilled labor needed in setting the slab are carpenters for setting the forms, roofersjto, handle waterproofin of the v slab, iron workers to tie in reinforcing steel and'lay wire mesh, plumbers, whose functionis'to' install necessary piping and fixtures, and., ?qm nt finishers to 'place' a'ndfinish the concrete. Aft'efpourin'gthe slab, carpenters must again be utilized to strip the forms and laborers must be directed to move the necessary materialandclean' 'excess debris from the lot1"-More carpentersare -then'rneeessary to frame the house electricians-inust 'b'e us'ed towire it, and a crew of "insulators'utilized to apply sheeting and to insulate the interiorfwallsl I Roofers "must-then "be directed to apply the 'roofin'g'yand yet'another ciew td'apply the sheet rock. Painters must then tape, float and paint the structure interior, tilernen must be available'to install the floors, and carpenters direct'ed to place the cabinets and Formica. Ne'xtth'e bricklayer's must brick the exterior of the house andthbperating en" item must return to grade the lot From aconsideration of the above simplified illustration, it' is" obvious that current construction techniques involvetheuse of many skilled crafts, which, in combina- 1 tioii with high material costs, effects a "high 'cost at construction which mus'fibe'passed on to the ownerof the v hoine "or" other structure" being built; "Furthermore, stud -t'h'atffthe"'eostfof construction has increased each our year tdyeana'ndis likely "to continue doing Batik-2m fiicilent' insulating properties, and the ex- 7 3,827,895 Patented Aug. 6, 1974 pense of providing necessary strength. Nor does the addito be unsatisfactory as a poured-in-place, all inclusive material of construction for walls and roof structure, since the cost of this material is so great and it is subject to severe limitations regarding insulation and shock resistant properties. Furthermore, the cost of precast panels because, 1
built of these materials is generally prohibitive, of high transportation and erection costs.
SUMMARY OF THE INVENTION drilled, and is readily formed to provide a simulated brick or other outer structure having a pleasing appearance, and simulated sheetrock or other desired interior structure. The composition is also fireproof, waterproof,
vermin resistant, rot proof, wind resistant, erosion proof and storm proof, and is characterized by shock resistance and good insulating properties. In a typical embodiment of the invention, the mod-wall concrete composition may simulating textured gypsum board. The forms -utilized It has been found that the following basicv ingredients 5 may be combined to provide a composition having the characteristics heretofore noted: Water, gypsum, vermiculite, cement, wood fibers, and sisal. Additional preferred ingredients which may be added to aid shrink resistance and minimize porosity are calcium chloride and fly ash.
DESCRIPTION OF THE PREFERRED EMBODIMENTS It will be recognized that the materials heretofore set forth can be prepared in varyingproportions to provide compositions suitable for various environmental conditions. For example, the'g'ypsumzfrnaterial is introduced with cement, and preferably portlarld cement; which'isa high quality cement composition, to provide the necessary mixed in the composition in the range of from about 15% to about 40% by volume. Vermiculite'ris preferably added ,in (the proportion of f rom about 2% to about 29%. by-
insi 'latiomproperties. As' an additi wood fibers aref'pf erably a dded I the compos tlon in a volume perce tage'ranged fronifabou t about ,-2 T W0 5 fib rs w ch may Bea d the "far or sawdnstor'chips notexceedihg' about' I i an i'neh injdiarneten also serve to pre in the composition" for ,uselfin fearthqu "ck re 1st i e ltaas ss r Cesi m was i Accordingly, it is the purpose of this invention to provide a composition of matter which may be used to form the walls, slab and roof structure, as well as other 1 component parts of a structure, which composition has the necessary density, durability, and strength for func- 25 tional use. The composition may be readily poured into 1 any suitable mold, may be easily nailed, sawed and A function as a single wall composition having the abovenoted characteristics with the exterior walls having'the j same appearance as ordinary brick, and the interior walls structural strength, both ingredients being preferably volume in order to provide theconiposition withineeeslsary n tin tame H e s S a 4 such jf'California," fo'r' 'exampla wheres ch res tanc e 3 added to the mixture as desired, preferably in the volume percentage range of from about 0.25% to about 1%, in order to limit shrinkage and thereby increase the strength of the composition as it sets. It should be pointed out that under circumstances where calcium chloride is used, it is generally preferred not to use a greater than 1% by volume concentration, because such an excess tends to cause rapid setting of the composition mixture and frequently inhibits proper forming of the mixture as it is poured. However, under certain conditions where it is desired to effect a fast setting of the building material composition, larger percentages of calcium chloride may be used. Fly ash may also be selectively utilized in the composition to enhance waterproofing characteristics, and this ingredient is preferably added in a volume percentage of from about 0.25% to about 1%. It has been found that particulate fly ash or, in the alternative, limestone dust, will furnish the proper filling agent to fill the porous structure of the composition to provide the necessary waterproofing qualities. Sisal is also preferably utilized as a reinforcing agent to complement the gypsum and cement, and is preferably added in a volume percentage range of from about 1% to about 2%. Water is then added to the mixture in the proportion of about 3.5 gallons per cubic foot of mixture to provide the necessary fluidity. It will be appreciated that the concentration of water in the composition is not critical, it being necessary only to provide the necessary fluidity to effectuate pumping or otherwise facilitating entry of the composition mixture into the forms.
In a most preferred embodiment of the invention, the construction composition of this invention is composed of the following ingredients in the following volumetric proportions to effect optimum setting and curing conditions:
Gypsum-20% Vermiculite--29% Portland cement20% Wood fibers-28% Water-3.5 gallons/cubic foot of mixture.
It will be recognized that different types and grades of the material noted above such as gypsum or plasterboard, for example, may be utilized in the composition. Preferred among the mineral CaSO 21-1 which may be used are those gypsum compositions having. the trade names Hydrostone and Densacal Plaster, both trade names of which relate to high density CaSO 2H O, or gypsum. Ordinary gypsum may be utilized in the invention, but the above compositions are preferred due to greater strength. It will be appreciated that the vermiculite ingredient'may be selected from the group of micaceous minerals or hydrous silicates or mixtures of these, and particularly those derived from alteration of mica, the granules of which expand at high temperature to yield a lightweight, highly water absorbent material. Furthermore, the fly ash may be substantially any combustible ash which is a byproduct of combustible fuel, and the sisal ingredient is preferably small diameter cordage of short nap length, which will easily blend into the composition mixtute.
The invention will be better understood by a consideration 'of the following examples:
EXAMPLE I Twenty-eight pounds of gypsum, twent-eight' pounds of portland cement, four" pounds of calcium chloride, eight Calcium chloridel Fly ash-1 Sisal-1 pounds of limestone dust, three and one-half pounds of l vermiculite, twelve ounces of sisal, and se'venpounds of shredded wood fibers were placed in a mixing container, and'into this mixture was added three and one-half gallons of water. The composition was stirred to provides; uniforin r'nixirig, and was" noted to be viscousi'rhe mixture was then poured into a form for'testing and allowed to stand for twenty-eight days to curefAfter the curing period I thespecimen, whichwas observed to be a greyish brown in color, was broken under test conditions and was found to withstand one thousand pounds per square inch of pressure before failing. The density of the mix was found to be ninety-one pounds per cubic foot on a wet basis, and sixty-eight pounds per cubic foot on a dry basis. The compressive strength of similar samples computed on a time-of-curing basis was found to be as follows 2 hours-250 p.s.i. 28 days'1,000 p.s.i. 7 days-650 p.s.i.
EXAMPLE II A sample of the product illustrated in Example I was immersed in water for .48 hours,.:wiped dry, weighed, and placed in an oven and heated at 230 F. for 48 hours. The sample was then cooled in a sealed chamber, weighed, and the drying and cooling cycle repeated for' an additional 48 hour period'fiThe gravimetric results were as follows:
Initial wt. (lbs.)
Wt. after 48 hrs. sat (lbs.) 5.87 Wt. after initial drying (lbs.) 4.05
Linear shrinkage (percent) 0.0381
EXAMPLE III A sample of the product set forthin Example I was subjected to a test for flexural strength in accordance with ASTM standards, which strength was found to be as follows:
Total load (lbs.) 850 Flexural strength (p.s.i.) 330.6
EXAMPLE iv A sample of the product illustrated in Example I was Initial wt. (lbs.) g 5.25
Wt. after 8 hrs. sat (lbs.) 5.80 Dry wt. after 8 hrs. (lbs.) r 4.0 No. of freezing and thawing cycles 9O Adverse effects None While it will be recognized that the composition of this invention may be introduced into the forms by a variety of techniques, it is preferred to pump the mixture into the forms. This procedure ensures that the forms are uniformly filled, and effects a continuous and uninterrupted flow to avoid cold joints in the composition .as it hardens; after a firm set has been achieved, the forms are removed. I r
A preferred technique for introducing the mod-wall concrete composition into the forms is by pumping from a minimum of two discharge points on the pump, and curing is effected by allowing the mixture to,set for a specified period of time. Under ordinary circumstances, the setting time in the forms should not exceed 2 hours, after which the forms are removed. As heretofore noted, depending upon the particular design of the forms utilized,the outside.
of the structure may simulate a briclr or concrete surface and the inside can be designedto resemble a textured gypsum, which may be easily painted or otherwise decorated for finishing purposes..Other materials may be :sirnulated,.,
as desired, depending upon the form design. The material may be mill mixed to exact specifications with strict quality control, requiring only the addition of. water at the job site with no special plantor equipment. needed, to effect the desired composition. Furthermor qthe capability for.
producing a particular wall having particular specifications is limited only by the availability of the proper forms,,
mixer and equipment to pump the mix to the forms.
It is significant that under circumstances where additional insulating properties are required, either the wall thickness of the structure may be increased, the density of the mix reduced, or particular ingredients, such as wood fibers and vermiculite, may be added in increased quantities. Furthermore, the durability and permanency of the composition structure is essentially that of conventional concrete, and maintenance of the interior Wall is limited to that which would normally be required in conventional structures, such as painting, paneling, wallpapering and/or texturing. Since the wall is solid, the necessity of replacing torn and broken sheetrock as in conventional housing is removed, and the wall is capable of being nailed for installation of paneling, if desired. Furthermore, trim, molding, and accessories may be installed and adhesives applied for hanging wallpaper, as in conventional structures.
In addition to the superior qualities characteristic of the composition enumerated above, it is further significant that pouring of this product and the product itself is unaffected by wide temperature variation, since the composition will not freeze when poured in subzero temperatures due to the heat of hydration generated in the setting material. So long as the water can be added before it freezes, the mixture will not be adversely affected by either low or high temperature, and it can be poured when outside temperatures are as low as Fahrenheit. Furthermore, the pouring technique itself, as well as the composition mixture, is unaffected by hot and cold weather, freezing and thawing conditions, as well as varying humidity and other adverse weather conditions.
It is also significant that the composition of this invention may be readily adapted for use in any part of the United States as a material of construction due to its versatility. For example, it may be designed to withstand earthquake shocks prevalent on the West Coast by incorporating a high fiexure strength made possible by addition of higher concentrations of the wood fiber and sisal ingredients. The product may be made resistant to wind and ice storms by incorporating higher concentrations of cement and fly ash to enhance strength and water-impermeability characteristics. Similarly, the composition may be protected from the adverse effects of salty air found in the Gulf Coast states, and use of the monolithic pour technique vastly reduces the chance of overturning and collapse under load.
Other advantages of the composition of this invention are found in the features of self-reinforcement, which eliminates the need for steel reinforcement necessary in conventional concrete structures, and the capability of mill mixing to exact specifications, which produces a mixture requiring only the addition of water and mixing to ready the composition for pouring. As heretofore noted, the composition is also characterized by a rapid curing period after which the forms may be removed, and is shrink resistant, a feature which eliminates cracking and checking in the finished wall. Mod-wall concrete has an average flexural strength of 340 p.s.i., which compares to approximately p.s.i. for conventional concrete, and is essentially completely inert, as heretofore noted. The poured wall is also characterized by low density, a factor which produces excellent noise reduction qualities. Having described my invention with particularity, what is claimed is:
1. A construction composition comprising a volume percentage of from about 15% to about 20% gypsum, from about 9% to about 29% vermiculite, from about 15% to about 40% portland cement, from about 8% to about 28% wood fibers, from about 1% to about 2% sisal, and water in sufiicient quantity to make said composition fluid.
2. The construction composition of Claim 1 further comprising from about 0.25% to about 1% fly ash.
3-. The construction composition of Claim 1 further comprising from about 0.25% to about 1% calcium chloride.
4. The construction composition of Claim 1 further comprising from about 0.25 to about 1% fly ash and from about 0.25% to about 1% calcium chloride.
5. The composition of Claim 1 further including limestone in a volume percentage of from about 0.25% to about 1% and calcium chloride in a volume percentage of from about 0.25% to about 1%.
6. The composition of Claim 4 wherein: (a) said gypsum is present in a volume percentageof about 20%;
(b) said vermiculite is present in a volume percentage of about 29%;
(c) said portland cement is present in a volume percentage of about 20%;
(d) said wood fibers are present in a volume percentage of about 28%;
(e) said calcium chloride is present in a volume percentage of about 1%;
(f) said fly ash is present in a volume percentage of about 1%;
(g) said sisal is present in a volume percentage of about 1%; and
(h) said Water is present in a concentration of about 3 /2 gallons per cubic foot of said composition.
References Cited UNITED STATES PATENTS 3,565,648 2/1971 Mori et al. 10689 493,152 3/1893 Culver 106115 662,643 11/1900 Griswold 10699 767,434 8/1904 Perkins 10699 1,961,525 6/1934 Olfutt 10699 3,093,505 6/1963 Conway 10699 DELBERT E. GANTZ, Primary Examiner J. W. HELLWEGE, Assistant Examiner US. Cl. X.R. 10698,