Engineered concrete binder composition

Abstract

A novel engineered concrete binder composition providing overall reduced clinker factor and improved binding properties. The said concrete binder composition includes a primary binder in a ratio of 10-60 weight percent and a secondary binder in a ratio of 40-90 weight percent. The said primary binder is selected from a primary material group having spontaneous hydration property. The said secondary binder is selected from a secondary material group having induced hydration property.

Claims

1. A novel engineered concrete binder composition having overall reduced clinker factor, the concrete binder composition binding concrete aggregates to produce concrete material, wherein the said concrete binder composition comprises: at least one primary binder in a ratio of 10-60 weight percent, wherein the primary binder is selected from a primary material group having spontaneous hydration property; at least one secondary binder in a ratio of 40-90 weight percent, wherein the secondary binder is selected from a secondary material group having induced hydration property; the said primary binder comprises particles having a mode average particle diameter ranging from .sup.th to 1/25.sup.th of a smallest fine aggregate particle mode average particle diameter, the smallest fine aggregate mode average particle diameter referring to mode average particle diameter of smallest fine particles present in the concrete aggregates; the said secondary binder comprises particles having a mode average particle diameter ranging from .sup.th to 1/625.sup.th of the smallest fine aggregate mode average particle diameter; and the said primary material group and the said secondary material group form a Macro-Micro-Nano particle lattice arrangement to increase strength characteristics and durability index of the concrete material.

2. The novel engineered concrete binder composition as claimed in claim 1, wherein the said smallest fine aggregate mode average particle diameter is determined by the particle-size distribution (PSD) analysis of a smallest fine aggregate fraction of a raw concrete material.

3. The novel engineered concrete binder composition as claimed in claim 1, wherein the primary material group is selected from at least one of a normal Ordinary Portland Cement, a mechanically modified Ordinary Portland Cement, a chemically modified fly ash, a chemically modified blast furnace slag.

4. The novel engineered concrete binder composition as claimed in claim 1, wherein the said secondary material group is selected from at least a material imparting pozzolanic activity.

5. The novel engineered concrete binder composition as claimed in claim 4, wherein the said material imparting pozzolanic activity is selected from at least one of a natural pozzolanic material, an artificial pozzolanic material.

6. The novel engineered concrete binder composition as claimed in claim 5, wherein the said artificial pozzolanic material comprises: a chemically activated material selected from a fly ash, a blast furnace slag, a volcanic ash material, a quartz material, a pozzolanic material; and a mechanically modified material selected from a fly ash, a blast furnace slag, a volcanic ash material, a quartz material, a pozzolanic material.

7. The novel engineered concrete binder composition as claimed in claim 1 further comprises a rheology modifying agent, a pH modulator, a reaction activator.

8. The novel engineered concrete binder composition as claimed in claim 7, wherein the said rheology modifying agent is selected from one of lignosulfonate compounds, Polycarboxylate compound, Sulphonated naphthalene formaldehyde, Sulphonated melamine formaldehyde.

9. The novel engineered concrete binder composition as claimed in claim 7, wherein the said pH modulator is selected at least from one of hydroxide of alkali metal group, hydroxide of alkaline earth metal group.

10. The novel engineered concrete binder composition as claimed in claim 7, wherein the said reaction activator is selected from one of an oxide of the alkaline earth metal group, a hydroxide of the alkaline earth metal group, a carbonate of the alkaline earth metal group.

11. The novel engineered concrete binder composition as claimed in claim 1, wherein the said secondary material group is adapted to compactly occupy a void formed by a lattice arrangement of the said primary material group.

Description

DESCRIPTION OF THE DRAWING

(1) The advantages and features of the present invention will become better understood with reference to the following detailed description taken in conjunction with the accompanying drawings, in which:

(2) FIG. 1 illustrates the vacant voids at Macro-Micro-Nano level and shows the primary material group bonding based on face centered cubic lattice of the molecules.

(3) FIG. 2 illustrates the vacant voids at Macro-Micro-Nano level and shows the primary material group bonding based on body centered cubic lattice of the molecules.

(4) FIG. 3 illustrates the occupied voids of FIG. 1 at Macro-Micro-Nano level by the secondary material group to increase the strength characteristics and durability index of the invention.

(5) FIG. 4 illustrates the occupied voids of FIG. 2 at Macro-Micro-Nano level by the secondary material group to increase the strength characteristics and durability index of the invention.

DESCRIPTION OF THE INVENTION

(6) The exemplary embodiments described herein detail for illustrative purposes are subjected to many variations. It should be emphasized, however, that the present invention is not limited to the concrete binder composition. It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but these are intended to cover the application or implementation without departing from the spirit or scope of the present invention.

(7) Unless otherwise specified, the terms, which are used in the specification and claims, have the meanings commonly used in the field of infrastructure construction and cement/concrete industry. Specifically, the following terms have the meanings indicated below.

(8) The terms a and an herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.

(9) The terms having, comprising, including, and variations thereof signify the presence of a component.

(10) The term spontaneous hydration property refers to early and/or immediate hydration of a material when such material is mixed with water. Tricalcium silicate is an example of such spontaneous hydration property.

(11) The term induced hydration property refers to later, slow and/or time dependent hydration of a material when such material is mixed with water. Dicalcium silicate is an example of such induced hydration property.

(12) The term chemically activated material refers to a material which is chemically activated to achieve desired chemical reaction and/or results.

(13) The term mechanically modified material is understood to mean here a material whose particle size can be modified into a prerequisite particle size by applying a desired force and energy.

(14) The term pH modulator is understood to mean here a pH balancing agent. Specifically, in the present invention such pH modulator is referred to as a normal base compound which increases the basicity of the matrix.

(15) The term reaction activator is understood to mean here a compound which can facilitate a natural pozzolanic reaction to the fly ash.

(16) The term rheology modifying agent is understood to mean here a compound which can modify the viscosity and/or initial binding property of the concrete composition.

(17) It should be noted that the term pozzolanic activity as referenced hereinbelow means capability of binding calcium hydroxide in the presence of water as understood in the art.

(18) The mode average particle diameter as provided herein is understood to be the peak of the particle frequency distribution curve. In simple words the mode is the highest peak seen in the particle frequency distribution curve. The mode represents the particle size (or size range) most commonly found in the particle frequency distribution curve.

(19) The smallest fine aggregate mode average particle diameter is termed herein as the mode average particle diameter of the smallest fine particles present in the concrete aggregate. The smallest fine aggregate mode average particle diameter thus provides a clear cut idea of lattice arrangement of smallest particle of the concrete aggregate.

(20) Further, the particle-size distribution (PSD) analysis is termed herein as the mathematical expression of finding about the ratio/proportion of various particle size ranges which are present in given concrete aggregate sample. Generally, volume, area, length, and quantity are used as standard dimensions for determining the particle amount present in the concrete aggregate sample. However, volume of the concrete aggregate sample is considered as the easiest dimension and/or way of finding out the ratio of various particle size ranges present in the given concrete aggregate sample.

(21) Due to the current worldwide pressure of decreasing the CO.sub.2 emission, all the nations are looking for better technologies and products which produce lower carbon foot prints. Cement production is one of the major industry which produces very high amount of CO.sub.2. Hence, it is always desirable to find out better ways of cutting down the overall CO.sub.2 release during cement and concrete production. However, still this cannot be considered as the final and total solution of minimizing the CO.sub.2 release as cement and concrete production itself releases standard amount of CO.sub.2.

(22) There is another solution of reducing the use of cement in the concrete production but still the said cement reduction has adverse effect on the final strength of the concrete infrastructure. Accordingly, the present cement binder is engineered in such a way that it automatically reduces the overall use of cement and at the same time provides improved binding capabilities and higher strength to the final concrete infrastructure.

(23) The concrete binder composition as described in the present invention is a specially engineered concrete binder composition which ensures complete lattice packing of the concrete particles. The said lattice packing is engineered to the Macro-Micro-Nano level to ensure improved durability index of the final concrete structure.

(24) Further, the present concrete binder composition provides a means of better utilization of the pozzolanic materials in their production and at the same time shows enhancement of early strength characteristics despite of a substantial addition of pozzolanic materials.

(25) Accordingly, the present concrete binder composition is made up from at least one primary binder and at least one secondary binder. The said primary binder is present in a ratio of 10-60 weight percent and the said secondary binder is present in a ratio of 40-90 weight percent of the said concrete binder composition.

(26) The said primary binder is selected from a primary material group having spontaneous hydration property. It is to be well understood by a person skilled in the art that materials which shows such spontaneous hydration property can be selected from any one of Tricalcium silicate, Calcium hydroxide, Monosulfate, Monocarbonate and other know materials which shows such spontaneous hydration property. The said primary binder includes particles having a mode average particle diameter ranging from .sup.th to 1/25.sup.th of a smallest fine aggregate mode average particle diameter. It is well understood to a person skilled in the art that the said mode average particle diameter of the primary binder can be further modified as per the mode average particle diameter of the smallest fine aggregate particle of a particular concrete aggregate material.

(27) In a preferred embodiment, the said primary material group is selected from but not limited to at least one of a normal Ordinary Portland Cement, a mechanically modified Ordinary Portland Cement, a chemically modified fly ash, a chemically modified blast furnace slag. It is to be understood that the mechanically modified Ordinary Portland Cement is termed herein as modifying the Ordinary Portland Cement particle size to a desired size level via any of the process involving application of machines. The grinding, crushing, milling, steam jet milling with superheated steam, particle breakdown by electrical force, particle breakdown by magnetic force should be considered as the examples of application of machines for modifying the Ordinary Portland Cement particle size to a desired size level under the spirit of the present invention.

(28) Further, the smallest fine aggregate mode average particle diameter is determined by the particle-size distribution (PSD) analysis of the raw concrete material.

(29) In a preferred embodiment, the said secondary binder is selected from a secondary material group having induced hydration property. It is to be well understood by a person skilled in the art that materials which shows such induced hydration property can be selected from any one of compounds such as Dicalcium Silicate, Calcium Hydroxide, Fly Ash, materials imparting pozzolanic activity and other know materials which shows such induced hydration property. Wherein, the said materials imparting pozzolanic activity are selected from at least one of a natural pozzolanic material, an artificial pozzolanic material.

(30) In a preferred embodiment, the said artificial pozzolanic material is selected from at least one chemically activated material and at least one mechanically modified material. The said at least one chemically activated material and the said at least one mechanically modified material are selected from a fly ash, a blast furnace slag, a volcanic ash material, a quartz material, and/or a pozzolanic material.

(31) In an exemplary embodiment the said artificial pozzolanic material is selected from materials such as but not limited to Ground Granulated Blastfurnace Slag (GGBS); Lightweight Expanded Clay Aggregate (LECA); Pulverised Fuel Ash (PFA); Calcined Clay (Metastar); Microsilica (MS); Rice Husk Ash (RHA); Red Brick Dust (RBD); Tile and Yellow Brick Dust (YBD).

(32) Further, the said secondary binder comprises particles having a mode average particle diameter ranging from .sup.th to 1/625.sup.th of the smallest fine aggregate mode average particle diameter. It is well understood to a person skilled in the art that the said mode average particle diameter of the secondary binder can be further modified as per the demand and need of the smallest fine aggregate mode average particle diameter of the particular concrete aggregate raw materials.

(33) In yet another embodiment, the present novel engineered concrete binder composition also contains a rheology modifying agent selected from one of lignosulfonate compounds, Polycarboxylate compound, Sulphonated naphthalene formaldehyde, Sulphonated melamine formaldehyde.

(34) In yet another embodiment, the present novel engineered concrete binder composition also contains a pH modulator selected at least from one of hydroxide of alkali metal group, hydroxide of alkaline earth metal group. It is to be understood by a person skilled in the art that such pH modulator can be selected from at least one of a sodium hydroxide, potassium hydroxide, magnesium hydroxide, calcium hydroxide. Specifically, the said pH modulator is selected from calcium hydroxide.

(35) In yet another embodiment, the present novel engineered concrete binder composition also contains a reaction activator. The said reaction activator is selected from one of an oxide of the alkaline earth metal group such as magnesium oxide and calcium oxide, a hydroxide of the alkaline earth metal group such as magnesium hydroxide and calcium hydroxide, a carbonate of the alkaline earth metal group such as magnesium carbonate and calcium carbonate.

(36) In an exemplary embodiment, the said pH modulator and the reaction activator are subjected to chemically modify the said pozzolanic materials of the said secondary material group.

(37) In yet another embodiment, the said primary material group and the said secondary material group of the present novel engineered concrete binder composition form a Macro-Micro-Nano particle lattice arrangement to increase the strength characteristics and durability index of the final concrete material. Further, the said secondary binder is adapted to compactly occupy a void formed by a lattice arrangement of the primary material group.

(38) Thus, the aspects of the present invention are directed to an environmental friendly concrete binder composition having improved binding property. Further, the said engineered concrete binder composition improves the overall durability property of the final concrete structure.

(39) Particularly, the present concrete binder composition provides overall reduction of carbon foot prints, overall reduction in clinker factor, improved binding property, better utilization of pozzolanic materials in concrete production are some examples of the desired benefits achieved by the present invention.

(40) Best Mode of Working

(41) The best mode of working of the present invention provides a specially engineered concrete binder composition having compactly packed particle lattice arrangement ranging from Macro to Micro to Nano scale. The said concrete binder composition utilizes much reduced amount of cement materials while preparing the concrete admixture.

(42) Further, the said concrete binder composition contains high volume of pozzolanic materials as cement replacement for achieving maximum possible reduction of carbon footprint. Further, the said concrete binder composition also yields high early strengths as well as promises a high durability index to the finished product, especially concretes and ancillary concrete products.

(43) Specifically, the above said compactly packed particle lattice arrangement ranging from Macro to Micro to Nano scale is the backbone of the present specially engineered concrete binder composition. This particular property is achieved by determining the smallest fine aggregate mode average particle diameter of a given concrete raw material via the particle-size distribution (PSD) analysis. Now, a primary binder and a secondary binder are prepared based on the smallest fine aggregate mode average particle diameter.

(44) The said primary binder comprises particles having a mode average particle diameter ranging from .sup.th to 1/25.sup.th of the smallest fine aggregate mode average particle diameter. The said secondary binder comprises particles having a mode average particle diameter ranging from .sup.th to 1/625.sup.th of the smallest fine aggregate mode average particle diameter. It has to be noted down that such limitations of mode average particle diameter are provided herein for describing the present invention but the mode average particle diameter below these limitations has to be considered as under the scope of the invention.

(45) It is important to freeze the mode average particle diameter of the said primary binder as well as the said secondary binder in relation to the smallest fine aggregate mode average particle diameter (represented as S0) of a given concrete raw material. The said mode average particle diameter of the said primary binder as well as the said secondary binder is attained via various particle size modification processes and techniques such as but not limited to crushing, grinding, attrition, milling, jet milling with compressed air, jet milling with superheated steam, laser based particle breaking.

(46) In an exemplary embodiment, the mode average particle diameter of the said primary binder and the said secondary binder has to be understood by the examples of S1, S2, S3, S4 . . . SN mode average particle diameter. Where, the 51 mode average particle diameter is understood to be those particles whose mode average diameter is approximately .sup.th to .sup.th of the smallest fine aggregate mode average particle diameter (S0).

(47) Further, the S2 mode average particle diameter is understood to be the particles whose mode average diameter is approximately .sup.th to .sup.th of the particles having S1 mode average particle diameter. Accordingly, the S3 mode average particle diameter is understood to be the particles whose mode average diameter is approximately .sup.th to .sup.th of the particles having S2 mode average particle diameter. Similarly, the S4 mode average particle diameter is understood to be the particles whose mode average diameter is approximately .sup.th to .sup.th of the particles having S3 mode average particle diameter.

(48) This continuous series of different particle sizes having a defined mode average particle diameter is achieved via various particle size modification techniques ranging from mechanical to chemical treatment. This optimization of different particle sizes having a continuous series of different mode average particle diameters provides a complete packing of the particle lattice structure ranging from Macro-Micro-Nano level. This mixture provides a perfect particle chemistry to fill the maximum voids of the particle lattice structure and also improves concrete chemistry related to the early settings and the latter settings of the concrete material.

(49) Further, FIG. 1 and FIG. 2 illustrate the voids of the Body Centered Cubic (BCC) and Face Centered Cubic (FCC) lattice arrangements respectively. It is to be understood that the said primary binder and the said secondary binder are engineered to occupy this void space as formed by different particle lattice arrangements. The said primary binder and the said secondary binder are compactly arranged to occupy the void of one another particle and vice versa i.e. primary binder compactly packed within secondary binder and secondary binder compactly packed within primary binder and/or primary and secondary binder within primary binder and/or primary and secondary binder within secondary binder. Hence, a complete three dimensional particle packing is obtained for the final concrete binder.

(50) The smallest fine aggregate mode average particle diameter as described herein means the mode average particle diameter of the smallest fine particles of the concrete aggregate. The main purpose for determining the mode average particle diameter of the smallest fine particles of concrete aggregate is to know the optimum void structure of the concrete aggregate. Further, the knowledge of the optimum void structure of the concrete aggregate helps in filing the voids with the specially engineered materials. The said specially engineered materials are selected from at least one of Ordinary Portland Cement, Mechanically Modified Ordinary Portland Cement; and/or materials imparting pozzolonic activity such as but not limited to Ordinary Fly Ash, Mechanically Modified Fly Ash, Chemically Modified Fly Ash, Chemically Modified Blast Furnace Slag, Ground Granulated Blast Furnace Slag (GGBS), Lightweight Expanded Clay Aggregate (LECA), Pulverized Fuel Ash (PFA), Calcined Clay (Metastar), Microsilica (MS), Rice Husk Ash (RHA), Red Brick Dust (RBD), Tile And Yellow Brick Dust (YBD).

(51) All of the above materials are dried and mixed in their respective weight ratios into an appropriate blender to produce the final concert binder composition. The categorization i.e. primary binder and secondary binder and the ratio of such specially engineered materials is to be better understood via the various following examples.

(52) In one exemplary embodiment, the table 1 provides an example of the said concrete binder composition.

(53) TABLE-US-00001 TABLE 1 % by weight S. No. Material of total Primary Binders 1. Cement OPC 53G of around 3500 blains 30 of size S1 2. Chemically modified fly ash of size S1 20 3. Cement OPC 53G mechanically modified 10 of size S2 Secondary Binders 1. Unmodified Fly ash of size S1 20 2. Mechanically modified fly ash of size S2 15 3. Mechanically modified fly ash of size .sup.3-5 S3 or S4 Other Constituent 1. Rheology Modifying Agent 0.1-2

(54) In another embodiment, all these ingredients are blended uniformly in a blender and recommended to be used in a fashion similar to that of using a normal Ordinary Portland Cement (OPC), or normal Portland Pozzolana cement (PPC), or a normal Portland Slag Cement (PSC) used as concrete binders. It is however experimentally verified that by using the said novel engineered concrete binder composition having such significant proportions of micro and Nano particles, the rheology of the concrete mix is also modified, thus reducing the total water demand and thus increasing the final strength of the concrete structure.

(55) In yet another exemplary embodiment, the table 2 provides another example of the said concrete binder composition.

(56) TABLE-US-00002 TABLE 2 % by weight S. No. Material of total Primary Binders 1. Cement OPC 53G of around 3500 blains 20 of size S1 2. Chemically modified fly ash of size S1 20 3. Cement OPC 53G mechanically modified 10 of size S2 Secondary Binders 1. Unmodified Fly ash of size S1 30 2. Mechanically modified fly ash of size S2 18-20 Other Constituent 1. Rheology Modifying Agent 0.1-2.sup.

(57) In yet another exemplary embodiment, the table 3 provides another example of the said concrete binder composition.

(58) TABLE-US-00003 TABLE 3 % by weight S. No. Material of total 1. Cement original of size S1 70 2. Cement mechanically modified 20 of size S2 3. Cement mechanically modified of size 8-10 S3 or S4 Other Constituent 1. Rheology Modifying Agent 0.1-2

(59) After careful experimental observation it is concluded that the present specially engineered concrete binder composition satisfies all the mechanical properties, setting time property, chemical properties, fineness property as well as the production cost as required in the various concrete industry standards.

(60) The present invention provides several other advantages with respect to its use and binding property. The said concrete binder composition utilizes maximum amount of pozzolonic materials instead of ordinary Portland cement and at the same time provides improved strength setting properties as required in the concrete industry.

(61) While the invention has been described with respect to specific composition which include presently preferred modes of carrying out the invention, those skilled in the art will appreciate that there are numerous variations and permutations of the above described embodiments that fall within the spirit and scope of the invention. It should be understood that the invention is not limited in its application to the details of construction and arrangements of the components set forth herein. Variations and modifications of the foregoing are within the scope of the present invention.

(62) Accordingly, many variations of these embodiments are envisaged within the scope of the present invention.

(63) The foregoing descriptions of specific embodiments of the present invention have been presented for purposes of description. They are not intended to be exhaustive or to limit the present invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the present invention and its practical application, and to thereby enable others skilled in the art to best utilize the present invention and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions and substitutions of equivalents are contemplated as circumstances may suggest or render expedient, but such omissions and substitutions are intended to cover the application or implementation without departing from the spirit or scope of the present invention.