CZ278280B6 - Self-hardening suspension - Google Patents

Abstract

Self-hardening suspension consists of 0,9 to 30,0 per cent weight of cement, 1,5 to 20,0 per cent weight of puzzolane- -siliceous additive with minimum contains of silicon dioxide 80 per cent of weight, 50 to 89,3 per cent weight of bentonite suspension and 0,2 to 2,0 per cent of weight of plasticizing and and retardation additives with advantage on base of alkaline salts of lignosulfonate and sulfonated condensators of monovalent and polyvalent aromatic alcohols.

Description

The invention relates to a self-curing suspension used in civil engineering for building underground roofs and elements.

The self-setting suspensions hitherto used consist mainly of a cement binder, a clay suspension and chemical additives which regulate in particular the retardation, stability and rheological properties of the suspension in the liquid state. Self-hardening suspensions are used, in particular, in the manufacture of sealing underground walls, which achieve a reduction in water leakage into pits or interruption of permeable layers in the soil. As hydraulic binder in self-hardening suspensions, usually cements are used, in particular troscortland, optionally supplemented with other components such as fly ash, hydraulic lime, slag and the like. A disadvantage of self-hardening suspensions with a purely cementitious binder is that in an aggressive environment they have a reduced service life and cannot be used at all. To achieve a particularly high strength are required, relatively high doses of cement, which usually makes it difficult to retard the solidification of the slurry and increasing the abrasivity pro- _n centrifugated for mechanical parts hlbiacich device. The use of hydraulic lime as an additional cement binder increases strength but at the same time reduces resistance to aggressive environments. Self-curing suspensions with ash and ground slag are suitable for some types of aggressive environments. Their disadvantage is the high variability of the composition of these additives and their unavailability in the required uniform quality and, in the case of fly ash, also the need for high doses to achieve the desired mechanical properties. In some cases, the use of hitherto known self-curing suspensions is disadvantageous for a long cure time to achieve the prescribed mechanical properties, which is 2-5 months.

The above-mentioned drawbacks are solved by the invention, which is based on the fact that the self-hardening suspension consists of 9.0-30.0% by weight. cement, 1.5 - 20.0 wt.%, a puzzolane silica additive, preferably Si-drift or siloxide having a minimum silica content of 80.0 wt.%, 50.0 - 89.3 wt. % bentonite suspension and 0.2-2.0 wt. plasticizers and retardants, preferably based on alkali salts of lignosulfonates and sulfonated condensates of mono- and polyhydric aromatic alcohols. ^The self-curing suspension according to the invention has suitable rheological properties for deep-groove sheeting and by controlling the dosage of the individual material components the desired retardation time, higher hardness after curing, shorter curing time and higher resistance to aggressive water resistance are achieved compared to previously known self-curing suspensions. As a puzzolane siliceous additive, it is advantageous to use wastes from the production of ferro-silicon Si-drift or wastes from the production of silicon silicon containing at least 80.0% of silica. As plasticizing and retarding additives, alkali metal salts of lignosulfonates, known in practice under the trade names Ligoplast, respectively, can be used. Plasticizer S and additives based on sulfonated condensates of monovalent and polyvalent aromatic alcohols (Ralentol). Portland cement and troscortortland cement are preferably used as the cement component of the self-curing suspension according to the invention. The process of the invention saves a significant amount of energy-intensive cement.

-1GB 278280 B6

Application example 1

Self-hardening suspension according to the invention per 1 m ³ :

100 kg cement PC 400 kg Si-drift or siloxide

905 1 bentonite suspension

1 Ligoplast .1 Ralentol

After 1 month of curing, the hardened suspension has a simple compressive strength of 0.14 MPa and a filtration coefficient k = 5.10 ” ⁹ ms“ ¹ . The same parameters are achieved when using a cement self-hardening slurry with a composition of 1 m ³ :

250 kg cement PC 400

905 1 bentonite suspension

1 Ligoplast

1 Ralentol

The comparison shows that the process according to the invention saves 150 kg of cement per m ^{3 of} self-hardening suspension.

Application example 2

Self-hardening suspension according to the invention per 1 m ³ :

200 kg cement PC 400

100 kg Si-drift or Siloxide

885 1 bentonite suspension

1 Ligoplast

1 Ralentol

After 1 month of curing the hardened suspension has a simple compressive strength of 1.6 MPa and a filtration coefficient k = 3.10 ms. The same parameters are achieved when using a cement self-hardening slurry with a composition per 1 m ³ :

450 kg cement PC 400

820 1 bentonite suspension

1 Ligoplast

1 Ralentol

The comparison shows that the process according to the invention saves 250 kg of cement per 1 m ^{3 of} self-hardening suspension.

By varying the mixing ratio of the individual material components of the self-curing suspension according to the invention, the various physical-mechanical properties of the cured suspension can be achieved with considerable cement savings. At the same time, the underground wall filler according to the invention has a higher resistance to aggressive action of groundwater. The present invention can also be used for the preparation of injectable compositions, where a better penetration efficiency is achieved compared to cement or cement-based injectable compositions.

-2GB 278280 B6

Claims (1)

PATENT CLAIMS A self-curing suspension characterized in that it consists of 9.0-30.0 wt. % cement, 1.5 - 20.0 wt. % of the puzzolane siliceous additive preferably Si-dust or Siloxide with a minimum silica content of 80 wt.%, 50.0-89.3 wt. % bentonite suspension and 0.2-2.0 wt. plasticizers and retardants, preferably based on alkali salts of lignosulfonates and sulfonated condensates of mono- and polyhydric aromatic alcohols. End of document ø!