DESC:FIELD OF INVENTION
The present invention relates to a self-curing compound based formulation/ composition for concrete and a process for its preparation. The self-curing compound based formulation/ composition of the present invention as an additive is suitable for addition at the time of preparing the concrete/ plaster to advantageously avoid subsequent water curing.
The self-curing compound based formulation/ composition of the present invention enables concrete/plaster curing by synergizing water retention and improved reaction kinetics, and hence the efficiency attained is in terms of faster curing by involving lesser amount of water for curing concrete type materials including cement, plasters and the like allowing endured workability of concrete slump based on water retention, normalized controlled and uniform hydration thereby minimizing stress generation and plastic shrinkage based cracking tendencies without much compromising on curing time, while also achieving reduction in chloride ion permeability together with improved compressive strength by duly maintaining necessary flexural strength post curing. This also means curing of concrete/plaster type materials with no additional water curing, and to overcome the limitations vis-â-vis prior known conventional knowledge based on only one approach of either just water retention or only improved curing kinetics.
BACKGROUND ART
Water has always been the vital force for the humanity to survive globally. Under the domain of sustainable industrial practices, the emphasis is given on the saving of water at various stages across the value chain. The construction industry is consuming significant amount of water for the curing process which continues till 28 days. Various approaches are in practice where conventionally people have been using the water immersion (for the concrete objects), jute textile with frequent water spraying every day till the complete curing, various membranes which reduces the water evaporation from the concrete and similar approaches which can reduce the water evaporation or increase the water retention in the concrete composition to have the complete curing. All these approaches are labor intensive, consumes significant amount of water for ensuring complete curing of the concrete.
Globally, Researchers have been making efforts to address this challenge by varied technologies. Many of them are using water retention (Patents No.US 8,016,939 B2, as the approach and some of them uses catalysis to accelerate the concrete curing (Patents No. WO2021105824A1).
Patent no. WO2021105824A1, reveals the methodology to reduce the water curing by technologies that can help reduce water consumption for sustainable future by disclosing an admixture composition and its process for preparation. The admixture when used in concrete composition reduces the water requirement for curing. The admixture composition involved is based on components of alkali metal carbonate, alkali metal sulphate thickening agent, superabsorbent polymer, tertiary amine.
Patent no. US 8,016,939 B2 discloses the composition and its process for making the self-curing concrete. This prior composition claims self-curing concrete, self-curing agent can absorb moisture from atmosphere and then release the moisture into concrete for internal curing purpose. Adding specific amount of self-curing, the compressive strength of self-curing concrete may be increased at least 10% as compared to that of concrete without any curing. This prior art does not involve octyltriethoxysilane isomers.
Patent no. US2008072799A1 (B2), discloses the self-curing compound for concrete with self- curing agent absorbs moisture from air and then releases it into the concrete, thereby achieving self- curing without external curing method after placing. It uses polyvalent alcohol is selected from the group consisting of polyethylene glycol (PEG), propylene glycol (PG), dipropylene glycol (DPG), butylene glycol, neopently glycol (NPG), xylitol, sorbitol, glycerine and phytosterols. Self curing agent also uses self- curing agent is selected from the group consisting of hyaluronic acid, polyxyethylene (POE), sodium pyrrolidone carboxylate (PCA-Na), stearyl alcohol and cetyl alcohol. This prior art does not include any poly phosphate dispersant and also does not involve any octyltriethoxysilane isomers to provide additional performances in tandem together with self curing.
CN102145984A discloses the self curing composition with polyhydric alcohol and other components comprising hyaluronic acid, polyoxyethane, sodium pyrulidone carboxylate, sodium lactate, stearyl alcohol, whale Wax alcohol, sodium hydroxypyrrolidone, total polyglutamic acid and 3D super moisturizing hydrogel (sodium type), squalene, squalane, jojoba oil, tallow amide, hydrolyzed collagen, chitin derivatives, Aloe, seaweed extract, amino acid, vitamin B5, urea, fruit acid, lactic acid and their functionally similar substances and one of their derivatives, or a combination containing at least two of the above materials (inclusive) in different ratios. This prior art does not include any poly phosphate dispersant and also does not involve any octyltriethoxysilane isomers to provide additional performances in tandem together with self curing.
CN110746535A, discloses the composition of the curing compound for concrete.
KR102152589B1 claims a method for internal curing of concrete using plants powder, Internal curing of concrete using high absorbent resin (SAP)prepared by mixing acrylic acid and caustic soda, Plant powder-sheep horse (kenaf), hemp (hemp), jute (jute), manila hemp (abaca), or a mixed powder thereof. Polycarboxylic acid-water-reducing agent was superior in dispersing effect, main purpose is to improve the workability of concrete.
International Journal For Technological Research In Engineering, Volume 5, Issue 11, July-2018 under its abstract teaches curing that plays a major role in the construction of a building. And the major disadvantage of curing is the excess wastage of water in the form of rundown. In places where water is hard to find, places like Rajasthan, the process of curing becomes hard and costly also. To avoid the cons caused due to general curing, this experiment is conducted. The development of self-curing materials is now being considered for real engineering applications. In the past decade, there has been a huge interest in materials that can self-cure, and provide strength equal to that of general curing. Self-curing chemicals can be made from a variety of polymers and chemicals. In this prior art a few types of chemicals have been experimented and considered and are tested on cubes and cylinders to test its compressive strength and split tension for 3 days, 7 days and 28 days. M35 mix was considered as reference. The various conclusions obtained were presented. Self curing chemicals are stated to be 1. Polyethylene glycol 200, 2. Acrylic powder, 3. Concure water based chemicals.
Technical deficiencies found in prior art knowledge:
WO2021105824A1, reveals the methodology to reduce the water curing by innovative technologies that can help reduce water consumption for sustainable future. This invention discloses the admixture composition and its process for preparation. The admixture when used in concrete composition reduces the water requirement for curing. The composition uses alkali metal carbonate, alkali metal sulphate thickening agent, superabsorbent polymer, tertiary amine.
Patent no. US 8,016,939 B2 discloses the composition and its process for making the self-curing concrete. The composition claims self-curing concrete, self-curing agent can absorb moisture from atmosphere and then release the moisture into concrete for internal curing purpose. adding specific amount of self-curing, the compressive strength of self-curing concrete may be increased at least 10% as compared to that of concrete without any curing.
Patent no. US2008072799A1 (B2), discloses the self-curing compound for concrete with self- curing agent absorbs moisture from air and then releases it into the concrete, thereby achieving self- curing without external curing method after placing. It uses polyvalent alcohol is selected from the group consisting of polyethylene glycol (PEG), propylene glycol (PG), dipropylene glycol (DPG), butylene glycol, neopently glycol (NPG), xylitol, sorbitol, glycerine and phytosterols. Self-curing agent also uses self- curing agent is selected from the group consisting of hyaluronic acid, polyxyethylene (POE), sodium pyrrolidone carboxylate (PCA-Na), stearyl alcohol and cetyl alcohol.
CN102145984A discloses the self-curing composition with poly hydric alcohol and other components comprising hyaluronic acid, polyoxyethane, sodium pyrulidone carboxylate, sodium lactate, stearyl alcohol, whale Wax alcohol, sodium hydroxypyrrolidone, total polyglutamic acid and 3D super moisturizing hydrogel (sodium type), squalene, squalane, jojoba oil, tallow amide, hydrolyzed collagen, chitin derivatives, Aloe, seaweed extract, amino acid, vitamin B5, urea, fruit acid, lactic acid and their functionally similar substances and one of their derivatives, or a combination containing at least two of the above materials (inclusive) in different ratios.
CN110746535A, discloses the composition of the curing compound for concrete.
KR102152589B1 claims A method for internal curing of concrete using plants powder, Internal curing of concrete using high absorbent resin (SAP)prepared by mixing acrylic acid and caustic soda, Plant powder- sheep horse (kenaf), hemp (hemp), jute (jute), manila hemp (abaca), or a mixed powder thereof. Polycarboxylic acid-water-reducing agent superior in dispersing effect, main purpose is to improve the workability of concrete.
In spite of the above known conventional knowledge flowing from the art on curing of concrete/plaster, there is still a need in the art to provide for select formulations/ compositions with improved workability and pumpability, which upon addition to concrete would advantageously allow to not only avoid water curing but would additionally fortify the concrete with attributes of crack bridging ability/reduced crack formation and reduced permeability (chloride ion migration test).
Added to the above it is also needful to synergize water retention and improved reaction kinetics, to attain efficiency in terms of faster curing by involving lesser amount of water for curing concrete/plaster type materials including cement, plasters and the like. This also means to explore curing of the concrete/plaster type materials with no additional water curing, and to overcome the limitations vis-â-vis prior known conventional knowledge based on only one approach of either just water retention or only improved curing kinetics.

OBJECTS OF THE INVENTION
The basic object of the present invention is to provide for self-curing compound based formulation/ composition that would enable curing of concrete/plaster without water specifically in the areas of water inadequacies, heighted structure where the reach of water is limited or hot climates where temperature enables faster evaporation of water as evidenced by improved compressive strength over the control.
It is another object of the present invention to provide for said self-curing compound based formulation/ composition that would reduce the water evaporation from concrete/plaster hence making available enough water for the internal hydration process, that would in turn reduce manual intervention of water curing processes on concrete.
It is yet another object of the present invention to provide for said self-curing compound based formulation/ composition that would favour said internal curing of concrete/plaster facilitated by controlled and uniform hydration thereby minimizing the stress generation and hence would reduce tendencies for plastic shrinkage cracks.
It is another object of the present invention to provide for said self-curing compound based formulation/ composition which due to self-compacting and hydrophobizing, can also provide very good water resistance (by blocking the capillaries) to hence act as integral water proofing agent.
It is still another object of the present invention to provide for said self-curing compound based formulation/ composition that would be a synergistic combination of ingredients to provide for improved workability and pumpability, and would also cause reduction of chloride ion diffusion enabled by silane- siloxanes encapsulation in the formulation.
It is yet another object of the present invention to provide for said self-curing compound based formulation/ composition with the focus to enable concrete/plaster curing by synergizing water retention and improved reaction kinetics, to attain efficiency in terms of faster curing by involving lesser amount of water for curing concrete type materials including cement, plasters and the like, which would also be directed to curing of concrete/plaster type materials with no additional water curing, so as to overcome the limitations vis-â-vis prior known conventional knowledge based on only one approach of either just water retention or only improved curing kinetics.
SUMMARY OF THE INVENTION
Thus according to the basic aspect of the present invention there is provided a self-curing compound based formulation/composition of synergistic co-acting combination of ingredients in aqueous base comprising
(a) 5-20 wt.% preferably 16 wt.% Polyethylene Glycol-400;
(b) 1-25 wt.% preferably 14 wt% octyltriethoxy and iso-octyltriethoxy silane/ siloxane;
(c) 0.1-10 wt.% preferably 2.7 wt% Tri-ethanol amine (TEA);
(d) 1-20 wt.% preferably 7.2 wt.% Tri-isopropanol amine (TIPA).
Preferably said self curing compound based formulation/composition is provided suitable as additive for concrete/ plaster mix that could advantageously avoid subsequent water curing wherein said octyltriethoxy and iso-octyltriethoxy silane/ siloxane is a combination of monomeric–oligomeric component.
According to another preferred aspect of the present invention there is provided said self curing compound based formulation/composition wherein said formulation/composition together with water retaining, dispersing and defoaming ingredients preferably includes the following
5-70 wt.% water;
0.1 to 5 wt.% Laponite-RD;
0.5 to 5 wt.% Methyl hydroxyl ethyl cellulose/ poly vinyl alcohol (MHEC/PVA);
1 to 10 wt.% Sodium nitrate;
0.1 to 10 wt.% Sodium gluconate;
0.1 to 2 wt.% SHMP (Sodium hexametaphosphate);
5 to 25 wt.% Neo-pentyl glycol;
0.1 to 5 wt.% ethylene oxide-propylene oxide copolymer having mol. wt. preferably 1800 g/mol.
1 to 10 wt.% sodium ligno sulphonate;
0.1 to 2 wt.% hydrophilic fumed silica;
5 to 25 wt.% Polyethylene glycol-400;
0.1 to 10 wt.% Tri-ethanol amine 85% (TEA);
1 to 20 wt.% Tri-isopropanol amine 85% (TIPA)
1 to 25 wt.% octyltriethoxy and iso-octyltriethoxy silane/ siloxane;
1 to 30 wt.% polycarboxylate ether having mol. wt. Mn(g/mol)-8111 and Mw(g/mol)-27134;
1 to 10 wt.% Ethyl di-isopropyl amine (EDIPA);
1 to 10 wt.% Di-ethanol iso-propanol amine (DEIPA).

According to another preferred aspect of the present invention there is provided a self curing compound based formulation/composition wherein said formulation is a dark brown liquid free of any precipitate having pH in the range of 12-14, viscosity in the range of 50-80 KU at 30 ?C that is stable for at least 12 months.

Preferably said self curing compound based formulation/composition is provided wherein said formulation/composition in comprising said glycols in select levels preferably with polyvinyl alcohol along with the blend of said amines imparts best water retention to perfectly set concrete/plaster curing and together with said octyltriethoxysilanes isomers, imparts reduced permeability (chloride ion migration test) and reduced crack formation, and preferably with polyphosphate dispersant while enables sustained workability of cement concrete slump mix is not found to negatively affect the setting of concrete and its hydrophobization,
wherein said formulation when present in small dosages of 0.3-0.6 % by wt. of cement (BWOC) in concrete mixes having 0.8-1.3% by wt. of cement enables following characteristics:
retained concrete slump even after 120 mins;
rapid chloride ion permeability reduction of 20-35% over control;
compressive strength based on reduced water and subsequent air curing after 28 days is > 68 MPa, and, based on same water and subsequent air curing is > 55 MPa for cement: sand ratio of 1:3;
compressive strength based on reduced water and subsequent air curing after 28 days is > 46 MPa, for cement: sand ratio of 1:4;
flexural strength post 7 days and 28 days are >6MPa and >7 MPa for cement: sand ratio of 1:3, and, flexural strength post 7 days and 28 days are >5MPa and >6 MPa for cement: sand ratio of 1:4;
Peak Normalized heat flow 20-30 (Watt/g) for setting time of 7-9 hrs.
According to another aspect of the process of the present invention there is provided a process for manufacturing the self-curing compound based formulation/composition in aqueous base comprising the steps of:
blending in aqueous base said ingredients together with liquid ingredients and mixing free of any lump formation to attain homogeneity of solution enabling dark brown coloured liquid having pH (10-13) as self curing compound based formulation.
Preferably in said process for manufacturing the self-curing compound based formulation/composition as preferred formulation preferably of 1000 gm batch size is based on following steps:
a. Measuring 290.7 gm water in a vessel followed by slow addition of clay Laponite RD under 600-1000 RPM and mixed for 10 to 15 mins till the solution becomes homogenous followed by addition of ingredient Methyl hydroxy ethyl cellulose (MHEC)/PVA-21-75 grade Polyvinyl alcohol under same RPM for another 10 -15 mins till the solution becomes homogenous and lumps free;

b. Adding powder ingredients sodium nitrate, sodium gluconate, sodium hexa metaphosphate, Neopentyl glycol, Sodim lignosulfonate ingredients under stirring condition to the solution of step (a) and in the same vessel at RPM-200 to 600 for (3-5 mins) for ensuring the homogeneity checked visually on glass plate, with the prepared solution checked for clarity in pH range of 7-8 to which is subsequently added ethylene oxide-propylene oxide copolymer added under stirring;

c. Ensuring proper mixing of the resulting solution of step (b) to negate the presence of any lumpy materials powder based materials, followed by sodium ligno sulphonate ingredient and mixing continued under stirring at RPM-200-300 mixing for (3-5 mins) until the pH falls in range of 7-8 and formulation becomes dark brown colored liquid;

d. Slow addition of ingredient hydrophilic fumed silica in the solution of step (c) above under RPM 200-300 mixing for (3-5 mins) followed by subsequent addition of all other liquid ingredients Polyethylene glycol-400, Tri-ethanol amine 85% (TEA), Tri-isopropanol amine 85% (TIPA), octyltriethoxy and iso-octyltriethoxy silane/ siloxane, polycarboxylate ether having mol. wt. in the range including Mn(g/mol)-8111 and Mw(g/mol)-27134, Ethyl di-isopropyl amine (EDIPA), Di-ethanol iso-propanol amine (DEIPA) and stirring with RPM 200-400 that is continued for further 10-15 minutes after ensuring the homogeneity of solution with the appearance of solution remaining as dark brown coloured liquid having pH (10-13).
According to another aspect of the present invention there is provided said concrete slabs/cubes comprising
said self-curing compound based formulation/composition in small dosages of 0.3-0.6 % by weight of cement (BWOC) in concrete mixes having 0.8-1.3% by wt. of cement.
Preferably said concrete slabs/cubes is provided wherein said concrete mixes includes Ground granulated blast furnace slag (GGBS), crushed sand, micro silica, aggregates in the size range of 9-22 mm including coarse and fine aggregates, said aggregates being inert granular materials including gravel, crushed rocks.
More preferably said concrete slabs/cubes is provided augmented with the following attributes post casting and curing:
rapid chloride ion permeability reduction of 20-35% over control;
compressive strength based on reduced water and subsequent air curing after 28 days is > 68 MPa, and, based on same water and subsequent air curing is > 55 MPa for cement: sand ratio of 1:3;
compressive strength based on reduced water and subsequent air curing after 28 days is > 46 MPa, for cement: sand ratio of 1:4;
flexural strength post 7 days and 28 days are >6MPa and >7 MPa for cement: sand ratio of 1:3, and, flexural strength post 7 days and 28 days are >5MPa and >6 MPa for cement: sand ratio of 1:4;
Peak Normalized heat flow 20-30 (Watt/g) for setting time of 7-9 hrs.

BRIEF DESCRIPTION OF FIGURES
Figure 1: illustrates dry materials used for preparing the concrete compositions;
Figure 2: illustrates concrete Pan Mixture used for preparing the concrete compositions;
Figure 3: illustrates slump cone used for testing the slump of concrete mix;
Figure 4: illustrates slump images (initial and final) taken for different grades of concrete - initial slump of control (A) and experimental (B) compositions for M40 design;
Figure 5: illustrates initial slump flow of control (A) and experimental (B) compositions for M60;
Figure 6: illustrates initial slump flow of control (A) and experimental (B) compositions for M80;
Figure 7: illustrates half-filled concrete cubes for casting;
Figure 8: illustrates air curing of experimental cubes;
Figure 9A: illustrates water curing of control cubes;
Figure 9B: illustrates compressive strength;
Figure 10: illustrates encircled area shows the crack generation in concrete slab–kept in outdoor condition (a) Concrete Slab coated with Acrylic curing compound; (b) Concrete Slab casted with 0.55% dosage of self-curing; (c) Close-up view of cracks generated when kept outdoor;
Figure 11: CONTROL-Water curing;
Figure 12: EXPERIMENTAL-Air curing;
Figure 13: Experimental-2 days;
Figure 14: Control-2 days;
Figure 15: Experimental-2 days;
Figure 16: Control-2 days;
Figure 17: Experimental 28 days;
Figure 18: Control 28 days;
Figure 19: Experimental 28 days;
Figure 20: Control 28 days;
Figure 21: illustrates comparison graph showing normalised heat flow vs. time;
Figure 22: illustrates comparison accumulated heat (Q) of set 1 control vs. set 2 experimental;
Figure 23: illustrates comparison accumulated heat (Q) of set 3 control vs. set 4 experimental;
Figure 24: illustrates setting time for set 1, set 2, set 3, set 4;
Figure 25: illustrates peak normalized heat flow for set 1, set 2, set 3, set 4.

DETAILED DESCRIPTION OF THE INVENTION
As discussed hereinbefore, the present invention relates to a self-curing compound based formulation/ composition for concrete/plaster and a process for its preparation, wherein the self-curing formulation of the present invention as additive is suitable for addition into the formulation/ composition at the time of preparing the concrete/plaster to avoid subsequent water curing.
The approach of the present invention in one of its aspect is to provide for said select self-curing compound in the present formulation/ composition that enables water retention by including synergistic combination of ingredients of polyhydroxy substances including PEG, siloxanes in combination with curing accelerators such as selective blend of amines, which facilitates the workability for curing concrete in required time enabling early and later curing, to ensure the attainment of the final strength in line with the control (water cured standard) and also enables desired hydrophobizing towards improving the compactness to thereby reduce cracking tendencies and chloride ion diffusion.
In the present invention, concrete curing is enabled by synergizing the water retention and improved reaction kinetics, hence the efficiency (faster curing under lesser amount of water) of cement by addressing the aspect of cement curing. This also means the curing of the concrete with no additional water curing. The present invention also overcomes the limitations of the prior art with respect to using only one approach of either just water retention or only improved curing kinetics.
The approach of the present invention is directed to obtain a self-curing compound based formulation that is a synergistic combination of ingredients based on select water retentive polyhydroxy substances including PEG of varied molecular weights, silane/siloxanes together with curing accelerator combination including selective blend of amines that not only aids in early and later curing to ensure the attainment of the final strength of concrete similar to control (water cured standard), but also facilitates workability of the concrete slump for required time, together with desired hydrophobizing to also improve the compactness to thereby reduce the cracking tendencies and chloride ion diffusion. Preferably, polyvinyl alcohol of varied molecular weights can also be present in combination together with dispersants including PCEs (polycarboxylate ethers) to additionally facilitate water retention and workability of concrete slump for required time.
The present invention thus in incorporating glycols of specific grades preferably with polyvinyl alcohol imparts best water retention along with the blend of two amines to perfectly set the curing and together with octyltriethoxysilanes isomers, preferably iso-octyltriethoxysilane imparts performances like reduced permeability (chloride ion migration test) and reduced crack formation. The preferred involvement of polyphosphate dispersant while enables sustained workability of the cement concrete slump mix is not found to negatively affect the setting of concrete and its hydrophobization.
Added to the above, said self-curing compound based formulation of the present invention also meets the issues of pumpability requirements to facilitate mixing with concrete.The present invention formulation/ composition in including select polysiloxanes in presence of other components also including dispersants facilitates hydrophobizing and improves the compactness of the formulation to also reduce cracking tendencies and chloride ion diffusion of the formulation, and together meets the issues of workability and pumpability.
The formulation/ composition of the present invention preferably involves polyvinyl alcohol together with poly hydroxy compounds /glycols of specific grades which imparts best water retention along with the blend of two amines to perfectly set curing of concrete. The composition also preferably involves polyphosphate dispersant for sustained workability and pump ablility, and essentially involves a select combination of octyltriethoxysilanes isomers, for imparting additional performances like reduced permeability (chloride ion migration test) and reduced crack formation.

EXAMPLES:
Materials involved synergizing the attributes of the present self curing compound based formulation as is provided below under Table 1
The Table 1 below thus reveals the ingredients involved in select amounts and their specific roles providing for the synergistic attributes when present in select levels in the composition/formulation.

Table 1A: The essential ingredients involved and their role in the composition of the self-curing compound based formulation.

Sl. No. Ingredient Name Chemical Description Function Wt.% within preferred range Most Preferred/Essential wt.% range
1 PEG 400
Polyethylene Glycol-400, Molar mass: 380-420 g/mol Water retaining agent which reduces the water loss, improved workability of the composition 16 5-20
2 Silres BS-1701/Silres BS 8069/SMK1311
Octyltriethoxysilanes isomers, with iso-octyltriethoxysilane/ silane siloxane monomeric – oligomeric as the main component. Hydrophobizing of concrete and chloride ion diffusion control 14 4-20
3 TEA-85%
Tri-ethanol amine Accelerates hydration process of C3A (Tricalcium Aluminate) 2.7 0.5-5
4 TIPA-85%
Tri-isopropanol amine The involvement of TIPA facilitates the conversion of AFt to AFm [Calcium Aluminate Ferrite trisubstituted (AFt) to calcium aluminate ferrite monosubstituted (AFm)], which can be indicated from hydration heat. Additionally, TIPA can accelerate the dissolution of aluminate, silicate, and ferric into liquid paste. 7.2 2-9
5 Water Universal solvent For processing the formulation To balance

Table 1B: The ingredients including optional ingredients involved and their role in the composition of the self-curing compound based formulation
S.No. Ingredient’s Name Chemical description Function
1 PVA-21-7S (Kurarey, Japan) Polyvinyl alcohol Water retaining agent which reduces the water loss and improve the strength
2 MHEC Methyl hydroxy ethyl cellulose Water retention, rheology and workability of the concrete
3 PEG 400
(Huntsman)
Polyethylene Glycol-400 Water retaining agent which reduces the water loss, improved workability of the composition
4 Silres BS-1701/Silres BS 8069/SMK1311
Wacker Chemie AG octyltriethoxysilane isomers, with iso-octyltriethoxysilane / silane siloxane monomeric – oligomeric as the main component. Hydrophobizing of concrete and chloride ion diffusion control
5 SteroTEA-85%
Sterling Auxiliaries Tri-ethanol amine Accelerates hydration process of Tricalcium Aluminate (C3A)
6 Stero TIPA-85%
Sterling Auxiliaries Tri-isopropanol amine The use of TIPA facilitate the conversion of AFt to AFm, [Calcium Aluminate Ferrite trisubstituted (AFt) to calcium aluminate ferrite monosubstituted (AFm)], which can be indicated from hydration heat. Additionally, TIPA can accelerate the dissolution of aluminate, silicate, and ferric into liquid paste
7 HANSA 201 (S)
SAPPI Sodium-lignosulphonate
Dispersion along with water retention
8 Sodium Nitrate Sodium Nitrate Accelerator of cement hydration
9 NPG
Antares chem private limited Neo pentyl glycol Water retention and plasticity of concrete.
10 SHMP SHMP (Sodium hexametaphosphate): SHMP is used primarily for the dispersion of the concrete composition and thus improved workability and flow.
11 Jeffox WL -660
Indoarama Defoamer based on ethylene oxide- propylene oxide, 1800 g/mol, copolymer composition For taking care of the entrapped air and thus reduced porosity.
12 DEIPA 85%
Sterling Auxiliaries Di ethanol isopropanol amine Accelerates hydration process of Tricalcium Aluminate (C3A)
13 EDIPA 85% Ethyl di-isopropyl amine Accelerates hydration process of Tricalcium Aluminate (C3A) and di-calcium silicate (C2S)
14 DYN-M70
Aezisglobal Private Limited Polycarboxylate ether (WR), Mn(g/mol)-8111 and Mw(g/mol)-27134
Dispersing agent
15 Sodium Gluconate Sodium Gluconate Improved workability, retarding setting times
16 Laponite -RD
(BYK) Synthetic modified phyllosilicate Increases viscosity in the low shear range with a low impact in the high shear range, improves processability and storage stability
17 Aerosil 200
(Evonik) Hydrophilic fumed silica Anti-settling

Preparation process of preferred self-curing compound based formulation.
The process below describes the steps taken in preparing the self-curing compound. The experimental composition was prepared using the formulation given in table 2 below.

Table 2: Preferred self-curing compound based formulation/composition
S.No. Raw materials Preferred Wt.% For 1000 gm of batch Range %
1 Water 29.07 290.7 5 to 70
2 Laponite-RD 2.0 20 0.1 to 5
3 MHEC/PVA-21-75 0.5 5 0.5 to 5
4 Sodium nitrate 4.5 45 1 to 10
5 Sodium gluconate 0.4 4 0.1 to 10
6 SHMP 0.2 2 0.1 to 2
7 Neo pentyl glycol 9.7 97 5 to 25
8 Jeffox – WL 660 0.9 9 0.1 to 5
9 Sodium ligno sulphonate 4.5 45 1 to 10
10 Aerosil 200 0.73 7.3 0.1 to 2
11 Polyethylene glycol -400 16.5 165 5 to 25
12 TEA -85% 2.7 27 0.1 to 10
13 TIPA-85% 7.2 72 1 to 20
14 Silres BS-1701/Silres BS 8069/SMK 1311 (active content) 14.4 144 1 to 25
15 DYN-M70 2.5 25 1 to 30
16 EDIPA-85% 2.7 27 0.1 to 10
17 DEIPA-85% 1.5 15 0.1 to 10
Total 100 1000

Preparation process of 1000 gms of the laboratory batch for composition mentioned in Table No. 2
• In the above composition, after measuring 290.7 gm water in a vessel slow addition of S.No.2 ingredient (Laponite RD) done under 600-1000 RPM and mixed for 10 to 15 mins till the solution becomes homogenous followed by addition of S.No.3 ingredient MHEC/PVA-21-75 grade under same RPM for another 10 -15 mins till the solution becomes homogenous and lumps free.
• Now powder ingredients S.No. 4 to 7 ingredients (stated amount as table 2) were added under stirring condition same vessel at RPM-200 to 600 for (3-5 mins) for ensuring the homogeneity checked visually on glass plate, the prepared solution appears clear having pH in range of 7-8. Subsequently the S. No 8(stated amount as table 2) was added under stirring.
• After ensuring proper mixing and no lumps remaining of powder materials, addition of S.No.9 ingredient (stated amount as table 2) and continue stirring at RPM-200-300 mixing for (3-5 mins) the pH falls in range of 7-8 and composition becomes dark brown in color.
• Slow addition of S.No.10 ingredient (stated amount as table 2) under RPM 200-300 mixing for (3-5 mins) followed by subsequent addition of all other liquid ingredients S. No. 11 to 17 (stated amount as table 2) was done step wise as mentioned in above composition under stirring with RPM 200-400 and continued for further 10-15 minutes after ensuring the homogeneity of solution the appearance of solution is dark brown in colour having pH (10-13). Then the stirring was discontinued, and the experimental compositions were transferred to plastic containers and used for performance.
Physical properties of the self-curing compound formulation/ compositions:
The prepared self-curing compound as above was tested for the key physical properties using the standard test methods at 30 degree centigrade temperature.
Table 3: Physical properties of the above formulation
Sr.No. Properties Results
1 Appearance (free of any precipitates, settled solids) Dark brown liquid
2 pH (pH paper) 12-14
3 Stable Viscosity by Brookfield viscometer (30 °C) stable for 12 months 50 to 80 KU
4 WPL (weight per litre) 1.05-1.15 (gm/ml)

Test methods used in evaluation of self-curing compounds based formulation:
Table No. 4. Test methods used
S.No. Test Conducted IS/ASTM Codes
1 Concrete mix design IS-10262
2 METHODS OF SAMPLING AND ANALYSIS OF CONCRETE IS-1199-1959
3 METHODS OF TEST FOR STRENGTH OF CONCRETE IS-516-1959
4 Compressive strength Test of cement Mortar Cube IS 4031 Part 6
5 RCPT (Rapid Chloride ion permeability test) ASTM C1202
6 Isothermal Calorimetry ASTM C1679-09

PREPARATION PROCESS AND TESTING FOR CONCRETE CUBES CASTING:
Materials used and their properties:
Table No. 5. Physical properties of Material used
Materials Used Water absorption %
Aggregates 20mm 2.21
Aggregates 10mm 2.28
Crushed Sand 3.50

The aggregates are inert granular materials such as gravel, crushed rocks and along with water and cement it becomes an essential ingredient in concrete and only differs based on their size and termed as coarse and fine aggregates.
Process of preparing the concrete cubes:
Following process was followed for preparing the concrete cubes for the performance evaluation of the self-curing compound.

Table. 6. Mix design for Concrete Casting:
SAMPLE MIXES WITH CONCRETE (M40/M60/M80)
In this designation ‘M’ refers to the mix and the number specifies the characteristic compressive strength of the mix that it generates in N/ mm2.
Dry weight (Kg/m3)
Dry Ingredients Source M40 M60 M80
Cement Ultratech OPC 53 375 (14.7% by wt) 450 (17.5% by wt.) 450 (17.8% by wt.
Ground granulated blast furnace slag (GGBS) JSW Steel Limited 100 158 180
Micro silica Corniche India Pvt. Ltd. - 35 40
Aggregates 10 mm Vasai Mumbai 440 480 470
Aggregates 20 mm Vasai Mumbai 634 550 510
Crushed sand Vasai Mumbai 849 730 720
Water Tap water 152 165 158

• Following dry ingredients (as per table 6) were weighed in the ratio according to the respective grade of concrete for preparing cubes having dimension of 150mm*150mm*150mm.
• Concrete mixing pan wiped off properly with semi-wet cloth.
• Coarser aggregates were added and mixed with cement and crushed sand until the coarser aggregate uniformly distributed throughout the batch.
• After ensuring uniform mixing of dry ingredients, addition of water was done along with mentioned admixtures (Table 7) for each set of mixing, mixing was done evenly until the concrete appear to be homogeneous and of the desired consistency.
• For the experimental composition, the self-curing compound was introduced along with the admixtures mentioned in table 7.
Note- For different grades of concrete the type of admixtures, their dosage and self-curing dosage will vary accordingly.
Table No. 7. Shows the type of concrete mixes and its dosage used for different grades of concrete.
Concrete mix design Sample type Grade Name Cement Dosage Self-curing compound formulation dosage, the dosage taken in % by weight of cement for Self-curing compound.
M40 PCE (polycarboxylate ether) based, not compatible with SNF (Sulphonated naphthalene formaldehyde) based samples.
PC200
S.C Maximoplast 1.3% by wt. of cement involved in concrete formulation trials as flowing from Table 6 and when considered together with PCE 0.55% BWOC (by wt. of cement)
M60 PCE based PC300
S.C Maximoplast 0.9% by wt. of cement (same as above) 0.55% BWOC
M80 PCE based PC300
S.C Maximoplast 1.1% by wt. of cement (same as above) 0.35% BWOC

As per table 6 above, for concrete cube casting, mixing and testing every set of concrete grades was prepared in below mentioned pattern
Control mix: Cube casting for control always done with addition of respective admixture (Table No. 6) along with water while mixing as per mentioned dosage in Table No. 6
Experimental mix (self-curing compound): Cube casting for experimental composition was done with addition of respective admixture along with self-curing compound dosage given as per mentioned in Table 7.
PHYSICAL TESTING FOR CONCRETE MIX:
After homogenous mixing of dry and wet ingredients the following physical properties of concrete was taken:

Concrete slump test:
Concrete slump test or slump cone test is to determine the workability or consistency of concrete mix prepared at the laboratory or the construction site during the progress of the work, which was carried out from batch to batch to check the uniform quality of concrete during the construction.
Procedure:
• Placing the slump cone on a smooth horizontal non-porous base plate.
• Filling of the slump cone with prepared concrete in three approximately equal layers.
• Tamping of each layer was done with 25 strokes over the cross-section of the mould.
• Removal of excess concrete and level the surface with a trowel.
• Raising the mould from the concrete slowly in vertical direction.
• Measuring the slump as the difference (in mm) between the height of the mould, and that of point of the specimen being tested.

The slump measured as per the below mentioned time intervals:
1. Initial Slump
2. Slump after 30 mins
3. Slump after 60 mins
4. Slump after 90 mins
5. Slump after 120 mins and continues till casting slump
Slump Retention Period- It defines the workability of concrete which is measured from the time of water addition in concrete mix till the concrete is poured, and better the slump retention better is the workability of the concrete.
Density- Density was measured for each set of mix including control and experimental at 30 degree centigrade. The results are given in Table No.8

Table No. 8. Shows the physical properties (slump, retention, density) checked for different grades of concrete:
Concrete grades M40 M60 M80
Physical Properties Control (water cured) Experimental Control
(water cured) Experimental Control(water cured) Experimental
Water/cement Ratio 0.37 0.37 0.28 0.28 0.26 0.26
Initial Slump(mm) 210 220
Initial diameter(mm) 500 530 580 520
Final slump(mm) 50 50 50 50 130 130
Retention(Hrs.) 04:00 04:30 03:00 03:15 06:00 06:00
Density(gm/cc) 2.59 2.6 2.56 2.6 2.55 2.57

CUBE CASTING PROCEDURE:
The below process was followed for preparing the cubes to assess the compressive strength of the concrete compositions.
1. Cleaning of moulds and application of lubricating oil.
2. Filling of concrete in moulds was done in 2- or 3-layers step wise.
3. Compacting each layer with giving strokes per layer by using tamping rod.
4. Leveling the top surface and smoothen it with trowel.
5. The filled concrete cubed was stored under lab condition for 24 hours.
6. After 24 hours, removed the specimen from the mould.
7. Coding of the casted cubes done with using permanent marker.

CURING OF CUBES
Casted cubes were kept for curing under different curing conditions which are mentioned below:
Control
All cubes submerged in clear fresh tape water until taken for the compressive strength test at different ages (3, 7& 28 days)- water curing.
Experimental
All cubes were kept under shaded area outside the lab in open environmental condition until taken out for compressive strength test at different ages (3, 7 & 28 days) - air curing
PROCEDURE FOR CONCRETE COMPRESSIVE STRENGTH TEST
The above cured concrete cubes were undertaken for compressive strength at various ages (3 days/ 7 days/ 28 days). CTM (compressive testing machine) was used for this evaluation. Below stepwise process was followed for the same.
Instrument-CTM
• Three cubes (the testing was done in triplicate to ensure the consistency in strength measurement) as prepared above were tested in CTM equipment after 3, 7 and 28 days aging.
• Removal of cube was done from water after specified curing time- and wiped-out excess water from the surface.
• Cleaning was done for the bearing surface of the testing machine.
• Placing the cube in the machine in such a manner that the load shall be applied to the opposite sides of the casted cube.
• Load was applied gradually, continuously at the pace rate of 5.2 KN/sec till the cube fails.
• Recorded the maximum load or measured stress by CTM.
• Formula to calculate Stress-Load/area in MPa.

The results are recorded in Table 9.
Table No. 9. SHOWS THE DATA OF COMPRESSIVE STRENGTH TESTING (MPa) TESTED IN 3, 7 & 28 DAYS FOR M40, M60 AND M80 GRADES OF CONCRETE

Concrete Grade M40 M60 M80
Experiments Control Experimental Control Experimental Control Experimental
Curing condition water air water air water air
Dosage
(% BWOC, by wt. of cement) Nil 0.55% Nil 0.55% Nil 0.35%
3Days (MPa) 41.19 41.85 48.40 50.81 52.06 53.5
7Days (Mpa) 54.31 57.78 69.81 71.07 77.01 79.17
28Days (Mpa) 63.26 73.81 84.4 88.36 92.59 96.56
The results in the above table clearly confirm that the experimental sets give relatively higher compressive strength than the control sets done with conventional water curing approach.

RAPID CHLORIDE ION PERMEABILITY TEST (RCPT-ASTM-C1202)
This test method is used to provide an indication on the chloride ion permeability in concrete. It is used for evaluation the resistance of a concrete against the penetration of chloride ions.

Table No.10. Result for RCPT (charge in coulomb)
Concrete Grades M-40
Experiments Control Experimental
Curing Conditions water air
Charge (coulomb) 3491 2351.5
% Reduction against the control, desired much less penetration Control 32.64%

Plastic Shrinkage Test [in Concrete Sample (M-40)
Plastic shrinkage test was done to check the early cracking on the concrete surface. The results of the experimental design against the control and water cured samples are shown in Fig. 10
Preparation steps to check plastic shrinkage in M40 grade of concrete:
• Following dry ingredients weighed and added in Concrete pan mixer as per mentioned in Table No. 11 for filling the square wooden frame having dimension of 3”*3”(as shown in Figure No. 13)
• After uniform mixing of dry ingredients water was added and casting of two concrete slab was done and one of the concrete slab coated with acrylic curing compound and another one casted with 0.55% dosage of self-curing (by weight of cement).
• Filling of the concrete mix was done up to a depth of 50-55 mm.
• Respective concrete slab kept under sunlight at a maximum temperature of 42-degree Celsius and 50% RH and shrinkage checked after 1:30 min from placing of slab.

Table No.11: Concrete Mix (M40) to check plastic shrinkage cracks
Mix Design
Concrete Grade M40
Raw Materials Source Dry Weight
Kg/m3
Cement Ultratech -OPC 53 380
Aggregates 10 mm Local-Mumbai 600
Aggregates 20 mm Local-Mumbai 480
Crushed Sand Local-Mumbai 900
Total Water 275
W/C (water-concrete ratio) 0.72
Admixture Not taken


PREPARATION PROCESS FOR MORTAR CUBE CASTING AND IT’S TESTING: All casting done at temperature and R.H27±2 or 65±5
Table No. 12: Properties of sand and cement
Dry Ingredients Source Size(mm) Moisture Content
Cement Ultratech OPC 53 NA NA
Standard Sand Type 1 Graded Sand (IS 269) 0.09mm-0.5mm 0.5 %
Standard Sand Type 1 Graded Sand (IS 269) 0.5mm-1mm 0.5 %
Standard Sand Type 1 Graded Sand (IS 269) 1.0mm-2.0mm 0.5 %

Step 1. Weighing of sand and cement
Following raw materials were added in the mentioned mixing ratio (Table No. 13) for preparing each mortar cube having dimension of 70.6mm*70.6mm*70.6mm Cement OPC 53
• Standard Sand Type 1-0.09mm-0.5mm
• Standard Sand Type 2- 0.5mm-1mm
• Standard Sand Type 3- 1.0mm-2.0mm

Table No.13. Experimental composition for preparing Mortar cubes
Raw Materials Wt.(gm)
Cement OPC 53 200
Standard Sand Type 1 200
Standard Sand Type 2 200
Standard Sand Type 3 200

Step 2. Mixing of cement and sand in dry form was done and after that addition of water along with experimental dosage of self-curing compound formulation as per Table 2 formulation was taken until the mixture will get homogenous and uniform colour.
Note-In mortar testing the experimental dosage of was taken 0.5% by weight of cement.
Step 3. Physical Parameters testing of Mortar:
• Flow
• Workability
• Density
Table No. 14. Physical properties of Mortar 1:3 (Cement: Sand Ratio)
Experiments with water reduction in same water
Mortar Properties Control Experimental 1 Control Experimental
Experimental Dosage by Wt. of cement (%, BWOC) of self-curing compound formulation as per Table 2 0.5 0.5
Cement: Sand Ratio
1:3
1:3
1:3
1:3
W/C (water–cement) Ratio 0.44 0.40 0.44 0.44
Water Reduction in % as desired 9.09
Initial Flow (mm) 155 155 155 180
Final Flow(mm) 140 140 140 140
Workability(min) 20 20 20 30
Initial Density(gm/ml) 2.25 2.26 2.25 2.22
Final Density (gm/ml) 2.26 2.27 2.26 2.25

From the results in Table above, we can see that in spite of the reduced water, the workability of the experimental set is either same or found relatively superior compared the control.
Step 4. Cube Casting
• Cleaning of moulds and application of lubricating oil.
• Filling of mortar in moulds was done in 2- or 3-layers step wise.
• Compacting each layer with giving strokes per layer by using tamping rod.
• Levelling the top surface and smoothen it with trowel.
• The filled cubes were stored under lab condition for 24 hours.
• After 24 hours, the specimen was removed from the mould.
Step 5. Demoulding of cubes done after 24 Hours of casting
Step 6. Coding of the casted cubes done with using permanent marker.
Step 7. Placing for curing
Casted cubes kept for curing under different curing conditions which are mentioned below:
Control-All cubes submerged in clear fresh tape water until taken out for the compressive strength test (water curing).
Experimental-All cubes kept under shaded area in outside the lab in natural environmental condition until taken out for compressive strength test (air curing).
Step 8. Compressive Strength Testing:
Instrument-CTM
• Three specimens tested in 3 days, three for 7 days and remaining three for 28 days
• Removal of specimen was done from water after specified curing time and wiped out excess water from the surface.
• Cleaning was done for the bearing surface of the testing machine.
• Placing the specimen in the machine in such a manner that the load shall be applied to the opposite sides of the casted cube.
• Load was applied gradually, continuously at the rate of 2.90 KN/sec till the specimen fails.
• Recorded the maximum load or measured stress by CTM.
• Formula to calculate Stress-Load/area in MPa.

Table No. 15. Compressive Strength Data for Mortar 1:3 (Cement: Sand Ratio)
Experiments With water reduction In same water
Days of testing Control Experimental 1 Control Experimental
Curing condition water air water air
3 Days (MPa) 36.73 41.06 25.4 27.16
7 Days (MPa) 41.2 54.16 37.84 40.06
28 Days (MPa) 53.38 68.13 48.4 55.06

The casting and compressive test study was also done in Mortar 1:4 (Cement: Sand Ratio) in a same way as done for Mortar 1:3 (Cement: Sand Ratio) and Table No. 16 and 17 below shows the results:
Table No. 16. Physical properties of Mortar 1:4 (Cement: Sand Ratio)
Mortar Properties Control Experimental
Experimental Dosage by Wt. of cement (%, BWOC) of self-curing compound formulation as per Table 2) 0.5
Cement: Sand Ratio 1:4 1:4
W/C Ratio 0.51 0.48
Water Reduction in % 5.88
Initial Flow (mm) 155 155
Final Flow(mm) 140 140
Workability(min) 15 15
Initial Density(gm/ml) 2.23 2.24
Final Density (gm/ml) 2.24 2.25

The above results confirms that the reduction of the water to cement ratio without affecting the workability

Table No. 17. Compressive Strength Data for Mortar 1:4 (Cement: Sand Ratio)
Experiments Mortar 1:4
Days of testing Control Experimental
Curing condition water air
3 Days (MPa) 23.79 30.08
7 Days (MPa) 31.34 37.42
28 Days (MPa) 39.3 46.89

Table No. 18. Flexural Strength of Mortar
Cement: Sand Ratio 1:3
Control 1:3
Experimental 1:4
Control 1:4
Experimental
7 days (MPa) 5.46 6.23 3.81 5.7
28 days (MPa) 7.37 7.02 6.16 6.47

SEM ANALYSIS
The SEM analysis was done to study the morphologies of casted concrete Grade M40 in control (water cured) vs. Experimental (air cured). The photos below at similar magnifications show the relative difference between the control and the experimental set with respect to the more compact morphology in case of experimental design. Thus, confirming the better and more complete cure in case of experimental design. This is evidence also in the results of the attaining the compressive strength above.
Isothermal Calorimetry
Introduction
A set of experiments were designed to record Isothermal colorimeter study using cement paste to do evaluation of heat of hydration, setting time in the presence Ultratech OPC 53 grade cement, GGBS (Ground Granulated Blast Furnace Slag)-JSW, Microsilica -Corniche India Pvt Ltd.
Table No. 19
Exp no. Product details Quantity (gm) Water (gm) Experimental
[Self-curing (gm)]
Set 1 Control -Cement 50 22.5 -
Set 2 Cement 50 22.5 0.25
Set 3 Cement 34.99 25.0
-

GGBS 12.27
Micro-silica 2.73
Set 4 Cement 34.99 25.0 0.25
GGBS 12.27
Micro-silica 2.73

Results and discussion
The cement paste was mixed as per procedure state above. The fresh cement paste was transferred to the 20 ml plastic ampoule and inserted in the calorimeter. The first data points were collected approximately 60 minutes after mixing to allow the time to reach equilibrium in the calorimeter.
The data from the isothermal calorimeter were exported and analyzed in Excel as shown in Figure 21. The heat development was normalized (mW/g) vs. time in hours which (dQ/dt) shown in Figure 22, 23. The set time is calculated as {½ x [maximum dQ/dt)] and plotted under Figure 24. Peak normalized heat flow for all the sets are given in Figure 25.
Table No.20: Peak Normalized heat flow, initial setting times, Peak time
Exp no. Product details Quantity (gm) Water (gm) Experimental
[Self-curing (gm)] Peak Normalized heat flow (Watt/g) Setting time in (hrs) ½*max (dQ/dt)
Set 1 Control-Cement 50 22.5 - 13.70 6hrs 53 min
Set 2 Cement 50 22.5 0.25 29.30 8hrs 50min
Set 3 Cement 34.99 25.0
-
19.84 6hrs 16min
GGBS, (Ground Granulated Blast Furnace Slag) 12.27
Micro-silica 2.73
Set 4 Cement 34.99 0.25 24.99 7hrs 50min
GGBS 12.27
Micro-silica 2.73

It is thus possible for the present advancement to provide for self-curing compound based formulation which when used applied in concrete has shown equivalent performance (without any additional water curing) in terms of workability, compressive strength, chloride ion permeability and shrinkage crack resistance when compared with control concrete cured under water in line with a wide scope of application of the present invention as below:
> Curing of concrete without water as demonstrated by retaining the respective curing performance properties for the experimental design Vs the control.
> Reduction of the water evaporation from the concrete hence making available enough water for the internal hydration process.
> Reduction of the tendencies for stress cracks by minimizing the stress generation due to uniform internal curing as demonstrated in the experiments.
> Improved workability and pumpability due to synergy of the ingredients in the composition.
> Good water resistance (by blocking the capillaries) due to self-compacting and hydrophobizing.
> Reduction of chloride ion diffusion due to the silane-siloxanes encapsulation.
Further advantages of the formulation/ composition of the present invention are as follows:
1. Curing of concrete/plaster without water specifically in the areas of water inadequacies, heighted structure where the reach of water is limited or hot climates where temperature enables faster evaporation of water as evidenced by improved compressive strength over the control.
2. To reduce the water evaporation from the concrete/plaster hence making available enough water for the internal hydration process, which can reduce the manual intervention for water curing processes.
3. The internal curing also facilitates controlled and uniform hydration thereby minimizing the stress generation and hence reducing the tendencies for plastic shrinkage cracks.
4. The composition is synergized for improved workability and pumpability.
5. Due to self-compacting and hydrophobizing, it also therefore provides very good water resistance (by blocking the capillaries) and hence also acts as integral water proofing agent.
6. Reduction of chloride ion diffusion due to the silane- siloxanes encapsulation.
7. Enables concrete/plaster curing by synergizing water retention together with improved reaction kinetics, hence efficiency is attained in terms of faster curing by involving lesser amount of water for curing concrete type materials including cement, plasters and the like. This also means curing of concrete/plaster type materials with no additional water curing, and to overcome the limitations vis-â-vis prior known conventional knowledge based on only one approach of either just water retention or only improved curing kinetics.

Advantageously, it is thus possible by way of the present invention to provide for said self-curing compound based formulation/ composition to enable curing of concrete/plaster devoid of water specifically in the areas of water inadequacies, heighted structures where the reach of water is limited or hot climates where temperature enables faster evaporation of water as found by improved compressive strength over the control, and could also meet the issues of reduced permeability (chloride ion migration test) and reduced crack formation, together with improvement in workability and pumpability, which also synergizes water retention together with improved reaction kinetics towards faster curing by involving lesser amount of water.
,CLAIMS:We Claim:

1. A self-curing compound based formulation/composition of synergistic co-acting combination of ingredients in aqueous base comprising
(a) 5-20 wt.% preferably 16 wt.% Polyethylene Glycol-400;
(b) 1-25 wt.% preferably 14 wt% octyltriethoxy and iso-octyltriethoxy silane/ siloxane;
(c) 0.1-10 wt.% preferably 2.7 wt% Tri-ethanol amine (TEA);
(d) 1-20 wt.% preferably 7.2 wt.% Tri-isopropanol amine (TIPA).

2. The self curing compound based formulation/composition as claimed in claim 1 suitable as additive for concrete/ plaster mix that could advantageously avoid subsequent water curing wherein said octyltriethoxy and iso-octyltriethoxy silane/ siloxane is a combination of monomeric–oligomeric component.

3. The self curing compound based formulation/composition as claimed in claims 1 or 2 wherein said formulation/composition together with water retaining, dispersing and defoaming ingredients preferably includes the following
5-70 wt.% water;
0.1 to 5 wt.% Laponite-RD;
0.5 to 5 wt.% Methyl hydroxyl ethyl cellulose/ poly vinyl alcohol (MHEC/PVA);
1 to 10 wt.% Sodium nitrate;
0.1 to 10 wt.% Sodium gluconate;
0.1 to 2 wt.% SHMP (Sodium hexametaphosphate);
5 to 25 wt.% Neo-pentyl glycol;
0.1 to 5 wt.% ethylene oxide-propylene oxide copolymer having mol. wt. preferably 1800 g/mol.
1 to 10 wt.% sodium ligno sulphonate;
0.1 to 2 wt.% hydrophilic fumed silica;
5 to 25 wt.% Polyethylene glycol-400;
0.1 to 10 wt.% Tri-ethanol amine 85% (TEA);
1 to 20 wt.% Tri-isopropanol amine 85% (TIPA)
1 to 25 wt.% octyltriethoxy and iso-octyltriethoxy silane/ siloxane;
1 to 30 wt.% polycarboxylate ether having mol. wt. Mn(g/mol)-8111 and Mw(g/mol)-27134;
1 to 10 wt.% Ethyl di-isopropyl amine (EDIPA);
1 to 10 wt.% Di-ethanol iso-propanol amine (DEIPA).

4. The self curing compound based formulation/composition as claimed in claims 1-3 wherein said formulation is a dark brown liquid free of any precipitate having pH in the range of 12-14, viscosity in the range of 50-80 KU at 30 ?C that is stable for at least 12 months.

5. The self curing compound based formulation/composition as claimed in claims 1-4 wherein said formulation/composition in comprising said glycols in select levels preferably with polyvinyl alcohol along with the blend of said amines imparts best water retention to perfectly set concrete/plaster curing and together with said octyltriethoxysilanes isomers, imparts reduced permeability (chloride ion migration test) and reduced crack formation, and preferably with polyphosphate dispersant while enables sustained workability of cement concrete slump mix is not found to negatively affect the setting of concrete and its hydrophobization,
wherein said formulation when present in small dosages of 0.3-0.6 % by wt. of cement (BWOC) in concrete mixes having 0.8-1.3% by wt. of cement enables following characteristics:
retained concrete slump even after 120 mins;
rapid chloride ion permeability reduction of 20-35% over control;
compressive strength based on reduced water and subsequent air curing after 28 days is > 68 MPa, and, based on same water and subsequent air curing is > 55 MPa for cement: sand ratio of 1:3;
compressive strength based on reduced water and subsequent air curing after 28 days is > 46 MPa, for cement: sand ratio of 1:4;
flexural strength post 7 days and 28 days are >6MPa and >7 MPa for cement: sand ratio of 1:3, and, flexural strength post 7 days and 28 days are >5MPa and >6 MPa for cement: sand ratio of 1:4;
Peak Normalized heat flow 20-30 (Watt/g) for setting time of 7-9 hrs.

6. A process for manufacturing the self-curing compound based formulation/composition as claimed in claims 1-5 in aqueous base comprising the steps of:
blending in aqueous base said ingredients together with liquid ingredients and mixing free of any lump formation to attain homogeneity of solution enabling dark brown coloured liquid having pH (10-13) as self curing compound based formulation.

7. The process for manufacturing the self-curing compound based formulation/composition as claimed in claim 6 as preferred formulation preferably of 1000 gm batch size based on following steps:
a. Measuring 290.7 gm water in a vessel followed by slow addition of clay Laponite RD under 600-1000 RPM and mixed for 10 to 15 mins till the solution becomes homogenous followed by addition of ingredient Methyl hydroxy ethyl cellulose (MHEC)/PVA-21-75 grade Polyvinyl alcohol under same RPM for another 10 -15 mins till the solution becomes homogenous and lumps free;

b. Adding powder ingredients sodium nitrate, sodium gluconate, sodium hexa metaphosphate, Neopentyl glycol, Sodim lignosulfonate ingredients under stirring condition to the solution of step (a) and in the same vessel at RPM-200 to 600 for (3-5 mins) for ensuring the homogeneity checked visually on glass plate, with the prepared solution checked for clarity in pH range of 7-8 to which is subsequently added ethylene oxide-propylene oxide copolymer added under stirring;

c. Ensuring proper mixing of the resulting solution of step (b) to negate the presence of any lumpy materials powder based materials, followed by sodium ligno sulphonate ingredient and mixing continued under stirring at RPM-200-300 mixing for (3-5 mins) until the pH falls in range of 7-8 and formulation becomes dark brown colored liquid;

d. Slow addition of ingredient hydrophilic fumed silica in the solution of step (c) above under RPM 200-300 mixing for (3-5 mins) followed by subsequent addition of all other liquid ingredients Polyethylene glycol-400, Tri-ethanol amine 85% (TEA), Tri-isopropanol amine 85% (TIPA), octyltriethoxy and iso-octyltriethoxy silane/ siloxane, polycarboxylate ether having mol. wt. in the range including Mn(g/mol)-8111 and Mw(g/mol)-27134, Ethyl di-isopropyl amine (EDIPA), Di-ethanol iso-propanol amine (DEIPA) and stirring with RPM 200-400 that is continued for further 10-15 minutes after ensuring the homogeneity of solution with the appearance of solution remaining as dark brown coloured liquid having pH (10-13).

8. Concrete slabs/cubes comprising
self-curing compound based formulation/composition as claimed in claims 1-5 in small dosages of 0.3-0.6 % by weight of cement (BWOC) in concrete mixes having 0.8-1.3% by wt. of cement.

9. Concrete slabs/cubes as claimed in claim 8 wherein said concrete mixes includes Ground granulated blast furnace slag (GGBS), crushed sand, micro silica, aggregates in the size range of 9-22 mm including coarse and fine aggregates, said aggregates being inert granular materials including gravel, crushed rocks.

10. Concrete slabs/cubes as claimed in claims 8 or 9 augmented with the following attributes post casting and curing:
rapid chloride ion permeability reduction of 20-35% over control;
compressive strength based on reduced water and subsequent air curing after 28 days is > 68 MPa, and, based on same water and subsequent air curing is > 55 MPa for cement: sand ratio of 1:3;
compressive strength based on reduced water and subsequent air curing after 28 days is > 46 MPa, for cement: sand ratio of 1:4;
flexural strength post 7 days and 28 days are >6MPa and >7 MPa for cement: sand ratio of 1:3, and, flexural strength post 7 days and 28 days are >5MPa and >6 MPa for cement: sand ratio of 1:4;
Peak Normalized heat flow 20-30 (Watt/g) for setting time of 7-9 hrs.

Dated the 20th day of March, 2024 Anjan Sen
(Applicants Agent & Advocate)
IN/PA-199