BS 890:1995 download free.Specification for Building limes.
1 Scope
BS 890 specifies requirements for building limes used as binders, predominantly in mortar for masonry as well as for rendering and plastering, and for limes used for soil stabilization. It gives a general definition of the different types of building limes and their classification. It also specifies requirements for their chemical, mechanical and physical properties, which depend on the type of building lime, and provides guidance on the manufacturer’s autocontrol procedures to ensure conformity.
Hydraulic limes are not covered by this standard.
2 References
2.1 Normative references
BS 890 incorporates, by dated or undated reference, provisions from other publications. These normative references are made at the appropriate places in the text and the cited publications are listed on the inside back cover. For dated references, only the edition cited applies: any subsequent amendments to or revisions of the cited publication apply to BS 890 only when incorporated in the reference by amendment or revision. For undated references, the latest edition of the cited publication applies, together with any amendments.
2.2 Informative references
BS 890 refers to other publications that provide information or guidance. Editions of these publications current at the time of issue of this standard are listed on the inside back cover, but reference should be made to the latest editions.
3 Definitions
For the purposes of this British Standard the definitions given in BS ISO 3534-1 apply, together with the following.
3.1
lime
any physical and chemical form of calcium oxide andlor hydroxide with lesser amounts of magnesium oxide and/or hydroxide
building limes
binders, the main constituents of which, on chemical analysis, are the oxides and hydroxides of calcium (CaO, Ca(OH)9), with lesser amounts of the oxides and hydroxides of magnesium (MgO, Mg(OH)9), silica (Si02), alumina (A1203) and ferric oxide (Fe2 O:)
3.3
air limes1
limes mainly consisting of calcium oxide or hydroxide which slowly harden in air by reacting with atmospheric carbon dioxide
NOTE Generally they do not harden under water as they have no hydraulic properties.
3.4
quicklimes
air limes mainly consisting of calcium oxide and magnesium oxide produced by calcination of limestone and/or dolomite rock
NOTE Quicklimes have an exothermic reaction when in contact with water. Quicklimes are offered in varying sizes ranging from lumps to finely ground materials.
3.5
burnt limes
quicklimes mainly consisting of calcium oxide
3.6
dolomitic limes
quicklimes mainly consisting of calcium oxide and magnesium oxide
3.7
slaked limes
air limes mainly consisting of calcium and possibly magnesium hydroxide resulting from the controlled slaking of quicklime
NOTE Slaked limes have no exothermic reaction when in contact with water. Slaked limes are produced in the form of a dry powder or as a slurry.
3.8
hydrated calcium limes
slaked limes mainly consisting of calcium hydroxide
3.9
hydrated dolomitic limes slaked limes mainly consisting of calcium hydroxide, magnesium hydroxide and magnesium oxide
3.10
semi-hydrated dolomitic limes
hydrated dolomitic limes mainly consisting of calcium hydroxide and magnesium oxide
3.11
completely hydrated dolomitic limes
hydrated dolomitic limes mainly consisting of calcium hydroxide and magnesium hydroxide
3.12
shell limes
slaked limes produced by calcination of shells followed by slaking
3.13
carbide limes
slaked limes which are a by-product of the manufacture of acetylene from calcium carbide
3.14
lime putties
slaked limes mixed with water to a desired consistence, mainly consisting of calcium hydroxide with or without magnesium hydroxide
4 Classification and notation
The different types of building lime shall be classified and identified according to their lime plus magnesia content (CaO + MgO) as foflciws:
— Calcium lime 90 CL 90
— Calcium lime 80 CL 80
— Calcium lime 70 CL 70
— Dolomitic lime 85 DL 85
— Dolomitic lime 80 DL 80
NOTE 1 This classification refers to minimum characteristic requirements for each class (see Table I and Table 2). Each type of lime can be supplied in the form of quicklime, hydrated lime or lime putty.
NOTE 2 Annex F describes the method for determining the class of a hydrated lime.
5 Chemical properties
When tested in accordance with BS EN 459-2, the chemical properties of building limes shall conform to the values given in Table 1. All types of lime listed in Table 1 are permitted to contain admixtures in small quantities. If the admixture content exceeds 0.1 %, the actual amount and types shall be declared. Admixtures shall have no detrimental effect on the properties of mortars.
7 Marking
Building lime conforming to this standard shall be marked, on the ha, if so supplied, the delivery note2, the invoice’ or any other accompanying documentation, with the following information:
a) type of building lime
b) commercial form of the type of building lime
(i.e. quicklime, hydrated lime or lime putty);
c) manufacturer’s name;
d) place of production;
e) working instructions if necessary;
f) safety information according to regulations;
g) type and amount of admixture if present in
excess of 0.1%;
h) number and year of this British Standard,
i.e. BS 890:1995’.
8 Information to be provided
The manufacturer shall, if so requested, state typical values for:
a) water demand (mortar test); b) water retention (by mortar test);
NOTE 1 Typical values lie in the range between 65 % and 85 %.
c) bulk density in kg/mm;
NOTE 2 Typical values lie in the following ranges CL 70/80/90: 300 to 600: DL 80/85: 400 to 600.
d) reactivity, Tmax and t (quicklime);
NOTE 3 In general, no requirements are specified for reactivity. If reactivity requirements are specified for particular uses, this should be agreed between the supplier and the purchaser.
The following values may be appropriate for lime used in soil stabilization: ground calcium limes CL 90 shculd reach a maximum temperature Tmax of not, less than 80 °C and all other ground limes should reach a maximum temperature of not less than 50 °C. The reaction time t for conversion of 80 % of the CaO content capable of being slaked should be less than 15 mm for all ground limes.
9 Sampling and testing for acceptance inspection
9.1 In order to assess conformity at delivery, when requested, a spot sample of the lime shall be taken in accordance with 3.6 and 6.2, 6.3, 6.4 or 6.5 of BS EN 196-7:1989 either before, or at the time of, delivery. A laboratory sample shall be prepared and packed in accordance with clauses 8 and 9 of BS EN 196-7:1989. A sampling report shall be completed at the time of sampling and shall be attached to the laboratory sample in accordance with clause 10 of BS EN 196-7:1989.
NOTE Testing may be delayed for up to 5 weeks from the time of sampling provided that there is confirmation that the sample has been stored continuously as described in 9.2 of
BS EN 196-7: 1989.
9.2 When the lime is tested for chemical properties (see clause 5), the sample shall be prepared by the method described in clause 6 of BS EN 196-2:1995.