Cement-based self-leveling mortar
Technical field
The present invention relates to building materials field, be specifically related to a kind of cement-based self-leveling mortar.
Background technology
Cement-based material, comprises sand-cement slurry and concrete, is the engineering materials that is widely used in ground.At present, guarantee terrace is smooth has with constructional method level:
(1), in the time that concrete floor (base plate) is constructed, adopt laser leveling machine leveling, troweling;
(2) on unfairness or out-of-level concrete floor, smear one deck mortar levelling layer.
The production method that existing mortar is conventional is: use silicate series cement as gelling material, using sand (particle diameter 0.160~4.75mm) for common building is aggregate, use various admixtures as water reducer (common, efficient or ultra-high efficiency), tackifier (ether of cellulose, rubber powder etc.), mineral admixture (flyash, breeze, silicon ash etc.), prepare the mortar of various use functions, for example masonry mortar, plastering mortar, thermal insulation mortar, waterproof mortar, mending mortar, decoration mortar, gravity flow self-leveling floor mortar, etc.Conventional mixing and stirring used production method to be: (1) is on-the-spot directly prepares burden and stirs, and is applicable to common performance mortar; (2) wet method premixing mortar, good in stirring station mixing, be transported to working-yard and use; (3) factory by all dry mash dry mixing evenly, packaging, scene only adds water to stir and just can use.For high function, the High Performance Mortar of batching more complicated, comprise insulation, waterproof, decoration, gravity flowing levelling mortar etc., generally adopt plant produced dry-mixed mortar, to ensure mortar quality and performance.
Adopt laser leveling machine construction concrete floor or road surface, be suitable for large-area industry ground slab, airport Zhan Pinghuo highway.Most indoor terraces or outdoor sclerosis floor construction, mainly rely on artificial levelling, and labour intensity is large, and levelling effect is decided by workman's state of the art, is difficult to ensure card construction quality.At present, on market, most gravity flowing levelling mortar products, because of meeting shrinkage cracking, can only be used for leveling up the level leveling of layer, can not be used for surface layer.Overcome in mortar use procedure self-constriction and dry shrinkage, be world-famous puzzle.At present, there is following technological line: (1) adopts silicate cement to prepare gravity flowing levelling mortar.Add swelling agent, as UEA, CSA etc., rely on swelling agent to produce autogenous shrinkage and dry shrinkage that expansion compensation cement hydrating hardening process produces.But the mechanism of intumescence of these swelling agents is moisture in absorbing environmental, produce dilatant mineral (calcium hydroxide or ettringite), the power resources that expand are in ambient moisture.Therefore, at dry environment, lack water supply, just cannot produce expansion.The expansion mineral that produce early stage at wet environment, the later stage, in dry environment, can decompose again, produces and shrinks and cracking.Theory and practice all proves, the swelling agent strong to water dependency, only at lasting wet environment, can effectively prevent contraction and the cracking of cement-based material; At drying and watering cycle environment, anti-contraction effect of anti-cracking is unreliable; Completely invalid at dry environment, even shrink with cracking more serious.(2) adopt aluminate cement to prepare gravity flowing levelling mortar.At present, international mature product all adopts this technological line, utilizes the contraction that aluminate is lower to prevent crack, and the enterprise that develops this product only has German Liang Ge company at present.But use aluminate cement to produce gravity flowing levelling mortar, technical difficulty is still higher, and not to use the mortar that aluminate cement is made just not to split.In addition, the price of aluminate cement is higher, uses the price of the gravity flowing levelling mortar product of aluminate cement making also to remain high, and has hindered its widespread use.Except the product of German Liang Ge enterprise, existing gravity flowing levelling mortar is as floor material, appearance crack that all can be in various degree when practical application.So in fact the product of other companies on market is only suitable for, for the levelling of terrace bed course, not being suitable for surface layer.Although and the Liang Ge enterprise gravity flowing levelling mortar floor material of Germany has overcome crack problem well, there is the shortcoming that cost is high, cost is high, hindered its application.
Summary of the invention
The present invention is directed to above-mentioned deficiency, provide that a kind of production cost is low, the cement-based self-leveling mortar of applied range.
Cement-based self-leveling mortar provided by the invention, the material that comprises following mass fraction: 0.2~0.6 part of 1~4 part of 0.01~0.05 part of ether of cellulose, latex powder, defoamer, 0.4~0.7 part of retardant that 100~200 parts of the quartz sands of 100 parts of quick hardening sulphoaluminate cements, 0.080~0.325mm particle diameter, 15~25 parts of β-semi-hydrated gypsums, 2~5 parts of silicon ashes, 1~1.5 part of polycarboxylate water-reducer, viscosity are 10000~50000MPas.
As the further improvement of cement-based self-leveling mortar of the present invention, described cement-based self-leveling mortar also comprises the not salts hardening accelerator higher than 0.3 part.
The mix using method of cement-based self-leveling mortar provided by the invention, identical with existing mortar mix using method, the amount of the mixing water mixing when difference is mix is 35~55 parts.
The present invention adopts quick hardening sulphoaluminate cement as basic gelling material, realizes mortar setting and harden, reaches intensity and wear resisting property that terrace mortar needs; Use quartz sand as aggregate, improve volume stability, intensity, the wear resistance of mortar; Use β-semi-hydrated gypsum, make aluminosulfate cement setting and harden process produce irreversible microdilatancy, after sclerosis, be exposed to dry environment and can not produce contraction and crack; Use powdery polycarboxylic acid water reducer, improve mortar mobility, realize Self-leveling performance;
Use silicon ash, ether of cellulose and latex powder, regulate mortar viscosity and water retention capacity, ensure high workability, gravity flowing levelling mortar not bleeding, do not emanate, quality uniformity after sclerosis improves the cohesive strength of gravity flowing levelling mortar and base material simultaneously; Use powdery defoamer, ensure that mortar is in plastic state, bubble can be got rid of fast, prevents that bubble and pore from appearring in gravity flowing levelling mortar surface, ensures that surfacing is smooth; Use the time of coagulation of Powdered retardant adjusting aluminosulfate cement, ensure the operable time of mortar; Use hardening accelerator to improve strength development.The present invention is taking aluminosulfate cement as basic gelling material, with quartz sand as aggregate, do not shrink with β-semi-hydrated gypsum control mortar, with other functional chemical admixture, make the mortar of preparation possess the over-all properties of requirement, newly mix performance and comprise high workability, Self-leveling performance, suitable operable time and Quick air-discharge bubble performance, Hardenability comprise not shrinkage cracking, higher-strength and higher wear resisting property (surface hardness) thus make fresh mortar of the present invention have high workability, Self-leveling, not bleeding, do not emanate; Hardened mortar does not shrink, does not ftracture, surface hardness is high, wear resisting property good.Do not shrink compared with indehiscent gravity flow self-leveling floor mortar product with existing, the raw material aluminosulfate cement that the present invention uses, price can reach existing and not shrink 1/4~1/10 of aluminate cement cost of material that indehiscent gravity flow self-leveling floor mortar uses, and product performance are identical.Taking aluminosulfate cement as basic gelling material, with quartz sand as aggregate, do not shrink with β-semi-hydrated gypsum control mortar, with other functional chemical admixture, make the mortar of preparation possess the over-all properties of requirement, newly mix performance and comprise high workability, Self-leveling performance, suitable operable time and Quick air-discharge bubble performance, Hardenability comprises shrinkage cracking not, higher intensity and wear resisting property (surface hardness).Therefore product of the present invention can significantly reduce production costs, thereby can apply more widely.Mortar of the present invention, due to can not shrinkage cracking, can be used for terrace surface layer, comprises new terrace levelling and surface decoration and the maintenance of level ground, once visited place or renovation, thereby has expanded the range of application of gravity flowing levelling mortar.
Embodiment
In order further to understand the present invention, below be explained with embodiment.It should be noted that, following examples only, as enumerating, should not be considered as the restriction to scope of the present invention.
Embodiment
Mixing water consumption when the raw material composition of the cement based terrace mortar of each embodiment and use is in table 1, the performance that fresh mortar after the cement based terrace mortar of different embodiment is mixed and stirred records and by the service condition of the terrace of its acquisition in table 2, wherein degree of mobilization testing method is shown in GB/T 50448-2008 " cement-based grouting material utilisation technology specification " appendix A .0.2; Operable time when degree of mobilization was construction in 30 minutes; Intensity test method is shown in GB/T 50448-2008 " cement-based grouting material utilisation technology specification " appendix A .0.4; Vertical expansion ratio, elliptical ring split test testing method are shown in GB/T 50448-2008 " cement-based grouting material utilisation technology specification " appendix A .0.5, and surface hardness adopts Mohs'hardness scale to measure.
Mixing water consumption (consumption unit is part) when the raw material composition of the cement based terrace mortar of the each embodiment of table 1 and use
The performance that fresh mortar after table 2 mixes and stirs the cement based terrace mortar of different embodiment records and by the service condition of the terrace of its acquisition.