SU1423531A1 - Method of preparing mortar - Google Patents

Abstract

The invention relates to the building materials industry and can be used in the manufacture of building mortars for masonry and plastering. The aim of the invention is to increase the crack resistance. The method of preparing the mortar involves introducing, with stirring, into a lime suspension, with a capacity of 1.23-1.28 g / cm and a temperature of 30-100 ° C, fly ash in an amount of 20-30% by weight of the suspension, ash suspension for 6-72 hours; diluting it with water with stirring at a shaft rotational speed of 0.52-9.1 for 0.5-1 minutes and then mixing with sand for 1-1.5 minutes. In addition, cement can be added when mixed with sand. The method provides strength of 305-520 kPa, thres-resistance, frost resistance of 26 cycles, 1 Cp. f-ly, 4 tab. Since cl

Description

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The invention relates to the industrial use of building materials and can be used in the preparation of building solutions for masonry and plastering.

The aim of the invention is to increase the crack resistance.

The following materials are used to prepare the solution: a lime suspension which is prepared for slaking lime; the suspension contains active CaO + MgO 25.1 L and non-extinguished grains 1.56%;

dry fly ash GRES with a specific surface 3100,. average density (bulk bulk density) of 1050 kg / m; chemical composition of ash SiO + +, 86.6%; MgO

1.76%; 2.39; sulfuric and sulphate compounds in terms of SOj 0.38% and ppt 0.63%, ash complies with GOST 25818-33;

Portland cement mark 400 with mineral additives (Shch-400-D20 - GOST 10178-85), strength at 28 days of age for stretching at bending 5.5 MPa and compressing 40.1 IPa; the beginning of the setting is 1 hour 35 minutes, the end is 7 hours ZO.MIN1 residue on sieve No. 008-12%, the cement shows the uniformity of the volume, the cement corresponds to GOST 10178-85.

natural quartz sand (ravine), modulus of particle size M | (1.31,

the content of dust and clay particles is 1.02%; grains larger than $ mm are absent sand according to GOST 8736-85.

; The preparation of the solution is carried out according to the following technology.

According to the prototype, all the components of the solution are introduced into the mixer in the following order: water, sand and limestone, making lime-sand IjiacTBopoB or water, ash, sand, assignor and lime suspension when imitating cement-lime mortars. Stir for .3 min. Samples are formed from semi-iJeHHoro solution.

Test methods.

I method - one-step mixing with water and double mixing. Initially, the calcareous suspension was smeared with ash, and sand for 1.5 minutes. The mixture is then incubated for 1 hour, the required quantity of water is added, re-mixed for 1.5 minutes and a lime-ash suspension is obtained. Method II - In the lime suspension, ash is introduced into the lime sludge process and a lime-ash suspension is obtained. Suspension mixing-. with the remaining components of the solution.

d The proposed method. The ash is mixed with a lime suspension in the process of quenching or with a heated progressed suspension and suspended. Then it is mixed with the necessary amount of water and a lime-ash suspension is obtained. Then the lime ash slurry is loaded into a mortar and the required amount of water is added. The required amount of water is determined mainly by the type of mortar (lime-sand or cement-lime), its required mobility and sand moisture. Water consumption in obtaining the results of the table. 1, in the manufacture of lime-sand mortar 33 liters and in the manufacture of cement-lime mortar 215 liters. After that in the mortar mixer

f. load sand and mix another 1-1.5 minutes

The composition of the lime-sand mortar: 1 mach. lime-ash suspension and 1.5 mas. sand.

The composition of the cement-lime solution: 1 wt.h. cement; 0.4 ma.ch. lime-ash suspension and 4 ma.ch. sand. If necessary, an additional amount of goals can be entered. The mobility of the freshly prepared solution, regardless of the method of preparation, is 10.5-12 cm.

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The crack resistance values determined by the ring method both in the time of the occurrence of the first crack t (the longer / longer the crack and resistance) 5 and the sum of the thicknesses (open) of the cracks formed 2cC (the smaller the crack opening, the higher the crack resistance), are given in table. T in the form of relative} values. At the same time, the values of t and ZcT for the lime-sand mortar, obtained by the prototype, and for the cement-lime mortar, obtained by separate introduction of lime suspension and ash, are 100% accepted.

The test results for mortar strength and crack resistance are given in Table. 1 and 2.

As follows from the table. 1, a decrease in the average density of the lime slurry to 1210 kg / m leads to a decrease in the strength of the solution both in compression and in tension when using the lime-ash slurry in cement-lime mortars improves their structural characteristics and thereby increases frost resistance.

Table 3 presents data on the parameters of the porosity of the solutions (at temperature, suspensions of AO C

This is due to the lack of lime in the mortar. Increasing the average density to 1300 kg / m does not provide

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aging for 2 h, stirring with water for 1 min and the rest of components 1.5 min.

As follows from the table. 3, the total porosity of the solution, which is akterized by a substantial increase in the crack-resistance-g total pore volume, is practically no bone, moreover, with such a dense change. When using the presentation, it is not always ensured that a thorough method increases the volume

The use of a lime-ash suspension in cement-lime mortars allows to improve their structural characteristics and thereby increase the frost resistance.

Table 3 presents data on the parameters of the porosity of the solutions (at temperature, suspensions of AO C

some mixing of the lime test t with finely dispersed ashes and and a zvestkovo-ash suspension and the mortar prepared on its basis have a heterogeneous mass; in this case, additional mixing costs are required.

The use of lime suspension with a high temperature without exposure Reduces the crack resistance of the mortar.

A decrease in the time required to maintain the lime-ash suspension to 5 hours leads to a decrease in the strength and crack resistance of the mortar, its properties practically do not differ from the prototype. Increase in: retention rates up to 80 hours is impractical, since construction indicators

the solution remains almost unchanged, and the productivity decreases. Reducing the ash content by up to 15% reduces the strength of concrete, and increasing it - up to 33% slightly decreases - aetrainine resistance and. results in a non-heterogeneous mass, in this case it is not necessary to add additional costs for mixing.

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Prototype

043 61 265 A50

I way

145 60 260 465

conditionally closed pores, which contributes to an increase in the frost resistance of building materials.

Claims (2)

In tab. 4 shows data on the frost resistance of mortars, manufactured by the known and proposed method. Invention Formula five one . The method of preparing mortar by mixing lime suspension, fly ash, water, and sand, characterized in that with a temperature of 30-100 ° C, fly ash is introduced with stirring in an amount of 20-30% by weight of the suspension; 1 second for 0.5-1 minutes, and then stirred. With sand for 1-1.5 minutes. 2. The method according to claim 1, about tl and h and y - y and with the fact that. While peemeshivanii lime-ash mixture with sand cement is introduced. Table 1 0 100 100 Uniform mass 98 98 Also 25 1250 Jii way o46 60 300 460 -PO 90 The proposed method 1250 40 P thirty 0.52 54 1250 W 72 (.З 10 57 85 345 525 Continuation of table Homogeneity of the solution Table 312 500 83 150 1600 80 158 1505 The full amount pore% 16.8 Volume of conditionally closed pores,% 6.2 Way Proposed 11.5 26 Prototype 11.0 12 Table 3 16,416.3 16.6 8, .58,67,8 Table 4 Cold resistance, cycle