BS 6319 standard :- Testing of resin flooring compositions for use in construction

e.g. epoxide, polyester, acrylic, polyurethane. These formulations may include liquid resins, liquid or powder hardeners, aggregates and fillers, and include polymer based grouts. 

• Compressive stress (nominal) :- The compressive force (in N/mm2) carried by the test piece per unit area of original cross section.

• Compressive strength :- The maximum stress (in N/mm2) carried by the test piece during a compressive test at the time of failure.

BS 6319 Part 3: Methods for measurement of modulus of elasticity in flexure and flexural strength

This Part of BS6319 describes methods for the measurement of modulus of elasticity in flexure and flexural strength of specimens of polymer based mortars and polymer/cement based mortars in the form of rectangular prisms.

• a) cracked hydraulic cement concrete repaired by resin injection

• b) hydraulic cement concrete with a resin composition topping or hydraulic cement concrete primed with a resin composition and built-up with a further layer of mortar or concrete 

• hardened hydraulic cement concrete bonded to hardened hydraulic cement concrete with a resin composition as, for example, when joining precast concrete units 

• Compressive stress (nominal) :- The compressive force (in N/mm2) carried by the test piece (at any time during the compressive test) per unit area of original cross section measured normal to the principal axis.

• Compressive strength :- The maximum stress (in N/mm2) carried by the test piece during a compressive test, at the time of failure.

• Slant shear bond strength :- The compressive strength (in N/mm2) of a scarf-jointed test piece 

This Part of BS6319 describes a method for the determination of the modulus of elasticity in compression of specimens of resin based mortars and concretes in the form of rectangular prisms.

• compressive stress :- the compressive force carried at any time by the test specimen per unit area of the original cross section

• compressive strain :- the ratio of the change in the distance between two reference points along the axis of the test specimen when related to their original spacing .

• elastic modulus :- the ratio of stress to corresponding strain below the proportional limit, where the proportional limit is the greatest stress which a material is capable of supporting without any deviation from proportionality of stress to strain (Hooke’s Law)

• secant modulus :-  the ratio of stress to corresponding strain measured relative to a level of pre-stress applied to bed firmly the specimen platens and ball seating. Accordingly, the secant modulus is based on the stress required to extend the gauge length of the test specimen by0.2% from a pre-stress of approximately10% of the expected force at0.002 strain.

BS 6319 Part 7: Method for measurement of tensile strength

This Part of BS6319describes a method for measurement of the tensile strength of resin based mortars and concretes cast in the form of dumb-bell shaped briquette test specimens. This method is not applicable to unfilled systems (see note1), or to materials having fibrous constituents (see note2) or to materials containing a filler that will not pass through a3.35mm test sieve as specified in BS410.

• tensile stress :- the tensile force carried by the test specimen per unit area of the original cross-sectional area of the central portion of the specimen .

• tensile strength :- the maximum tensile stress which the test specimen is capable of supporting.

BS 6319 Part 8: Method for the assessment of resistance to liquids

This Part of BS6319 describes a method for assessing the resistance to liquids of resin based mortars and concrete using the test for flexural strength described inBS6319-3.

The principle of the test is the comparison of the flexural strength of test specimens which have been exposed to chemical reagents under defined conditions with that of control specimens which have not been exposed to the reagents but which were prepared from the same batch of resin composition. Any changes in the mass and appearance of the specimen or test reagent during the test are observed and recorded

This Part of BS6319 describes a method of measurement for the peak exotherm temperature for resin based materials for use in the construction industry. A general guide-line for the classification of systems as “high, medium or low” exotherm is given inAppendix A

• The principle of this method is the determination of the temperature that a resin composition reaches after mixing the component parts together. The maximum temperature reached under standardized but not adiabatic laboratory conditions is recorded and reported as the peak exotherm temperature. 

BS 6319 Part 11: Methods for determination of creep in compression and in tension

This Part of BS6319 describes methods for the determination of the creep of specimens of polymer and polymer/cement mortars. Creep in compression is measured on rectangular prisms and creep in tension on necked specimens having a maximum aggregate size of2.4mm. 

The prime objective of the methods is to provide comparative data on materials in order to establish whether or not creep is likely to be significant in the intended application. 

The methods provide an estimate of creep strains within – 10% of the absolute value under the particular environmental conditions in which the test is conducted. 

For comparative purposes, it is necessary to control the temperature to within – 2 C of the specified temperature but control of humidity is not essential.

• Compressive stress :- force per unit area of the original cross section of a member in compression 

• Elastic strain :- deformation produced by a stress up to the elastic limit and expressed as the change per unit of original dimension.

• Elastic compressive strain :- elastic strain measured immediately following the application of compressive load.

• Tensile stress :- force per unit area of the original cross section of a member in tension

• Elastic tensile strain :- elastic strain measured immediately following the application of tensile load.

• Creep strain :- time-dependent strain measured over and above elastic strain under the application of a constant load.

• Creep coefficient :- ratio of creep strain to elastic strain at the same applied stress.

• Elastic recovery strain  :- amount of elastic strain lost by a member immediately on unloading to zero stress.

• Creep recovery strain  ;- amount of creep strain lost by a member following unloading to zero stress 

• Creep recovery coefficient  :- ratio of creep recovery strain to elastic recovery strain.

BS 6319 Part 12: Methods for measurement of unrestrained linear shrinkage and coefficient of thermal expansion :- 

This Part of BS6319 describes the methods for the measurement of linear shrinkage from initial gel and of the coefficient of thermal expansion of hardened polymer and polymer/cement mortars in the form of unrestrained thin strips (less than20mm in thickness). The methods are suitable for materials that do not contain aggregates larger than3mm used in thin layers for patch repairs and surfacing applications.

4.1 Shrinkage test 

 A freshly mixed sample of polymer mortar or polymer/cement mortar is placed in a shallow steel trough shaped mould with sliding ends, the inside of which has been treated to prevent adhesion by the mortar. The trough has sliding ends which bond to the mortar and are free to move as the mortar expands or contracts. Linear displacement transducers attached to the ends enable the shrinkage to be measured. A temperature sensor attached to the mould enables its temperature and so that of the mortar to be measured.

Coefficient of thermal expansion :- Samples of hardened polymer mortar or polymer/cement mortar, prepared as for the shrinkage test, are subjected to a number of temperature cycles while movements of the ends and changes in temperature of the mortar are monitored. Correction is made for changes in the length of the mould.