Información general sobre el sistema de gobernanza

Injection of cracks is specialist work. Control of workmanship can be performed by the supervisor monitoring the injection. Control of compliance with mixing time is particularly important. In case of doubt in the workmanship, unfilled cracks can be revealed by ‘impact echo’ and if necessary boring of a core where a thin section is analysed by UV radiation. Such an analysis is specialist work.

Table E2.7 Identification requirements for injection products formulated with reactive polymer binder Tolerance (% deviation Basic properties and characteristics Test method from data sheet)

Individual components

Epoxy equivalent EN 1877-1 Declared value ⫾5%

Amine functions EN 1877-2 Declared value ⫾6%

Hydroxyl value EN 1240 Declared value ⫾10%

Isocyanate content EN 1242 Declared value ⫾10%

Other functional groupsa _{Not specified}

⬃

Specific weight EN/ISO 2811-1 Declared value ⫾3%

Infrared analysisb _{EN 1767 Corresponding to ref.}

Identification of freshly mixed product

Viscosityc _{ISO 3219 Declared value ⫾20%}

Pot lifed _{EN ISO 9514 Declared value ⫾20%}

Volatile matter EN ISO 3251 Declared value ⫾5%

Identification of the hardened mixture

Tensile strength, elongation and elastic EN ISO 527-1 and 2 Declared value ⫾20% moduluse

Strength propertiesf

⬃ Declared value ⫾20%

a_{Determination of other components may be significant. However, no requirement or test standard is}

specified.

b_{The measured positions and relative intensities of the absorption strips should correspond to the reference}

given by the manufacturer.

c_{Viscosity should be measured 5 minutes after mixing of the product has been completed. The temperature}

of the components should be maintained at 21 ⫾ 2 °C before mixing. The temperature of the freshly mixed product should be measured and recorded. For injection materials which harden in less than 5 minutes, vis- cosity should be measured on unmixed components.

d_{The test should be in accordance with EN 9514, but a quantity of 1000 ml instead of 300 ml should be used}

and three conditioning and test temperatures should be used: 21 ⫾ 2 °C. The minimum use temperature recommended by the manufacturer/supplier with a tolerance of ⫾1 °C. The maximum use temperature rec- ommended by the manufacturer/supplier with a tolerance of ⫾1 °C. Pot life is defined as the period of time from when the mix was finished until: the temperature of the mix has risen 15 °C for polymeric injection materials, and the filtration stability is terminated by the value declared by the manufacturer/supplier for hydraulic injection materials.

e_{Only injection material for filling and other ductile injection materials should be tested according to}

EN 527-1. The test should be performed after 7 days of curing under standard conditions for polymeric injec- tion materials. The test should be performed on a poured sheet (thickness 3 mm) of the injection material concerned.

f_{The following method should only be applied to swelling injection materials: After 24 hours of curing at}

standard conditions, the injection material (from the pot life test) is subjected to a concentrated compressive load Ø 20 mm with conical head (top angle 60°) at a rate of 100 mm/min. The load–deformation curve should be recorded.

Reception control should be performed in accordance with the work specification for the rehabilitation work concerned with special control that the mixing time is observed.

Table E2.8 Identification requirements for injection products formulated with hydraulic binder Basic properties and characteristics Test method Tolerance (% deviation from data sheet)

Individual components

Particle size analysis by laser diffractiona _{ISO 13320-1 Reference}

Identification of freshly mixed product

Viscosity (Marsh Funnel)b _{EN 14117 Declared value ⫾20%}

Setting time EN 196-3 Declared value ⫾20%

Pot lifec _{EN 9514 Declared value ⫾20%}

Filtration stabilityd _{EN ISO 14497 Below prescribed value}

Identification of the hardened mixture

Compression strength and densitye _{EN 12190 Declared value ⫾15%}

a_{The measured particle size distribution should comply with the reference specified by the manufacturer.} b_{Viscosity should be measured 5 minutes after the mixing of the product. The temperature of components}

before mixing should be 21 ⫾ 2 °C.

c_{The test should be in accordance with EN 9514, but a quantity of 1000 ml instead of 300 ml should be used}

and three conditioning and test temperatures should be used: 21 ⫾ 2 °C. The minimum use temperature recommended by the manufacturer/supplier with a tolerance of ⫾1 °C. The maximum use temperature rec- ommended by the manufacturer/supplier with a tolerance of ⫾1 °C. Pot life is defined as the period of time from the mix has been finished until the temperature of the mix has risen 15 °C for polymeric injection materials, and the filtration stability is terminated by the value declared by the manufacturer/supplier for hydraulic injection materials.

d_{Filtration stability is defined as the ability of a hydraulic injection material to pass obstacles (in cracks)}

and cracks without ‘lumping’. This ‘lumping’ may be caused by: Too large cement particles; poor disper- sion; agglomeration (accumulation of cement particles) by injection of fine cracks or by contact with porous areas in the substrate.

e_{The test should be performed after 28 days of curing under standard conditions for hydraulic injection}

materials.

Table E2.9 Injection products for ductile filling of cracks

Properties and characteristics Test methods Compliance criteria

Basic properties

Effect on polymeric insertsa _{EN 12637-3 After 70 days, the changes in}

elongation should be lower than 20% of the initial value

Durability

Adhesion and elongation after EN 12618-1 and Adhesion. Loss of adhesion thermal and wet-drying cyclesb _{EN 13687-3 lower than 20% of the initial value}

Elongation: ⬎10%

a_{The contact with polymeric inserts may change the properties of an injection material by a chemical reac-}

tion whereby the injection material may lose its ductile properties.

b_{The adhesion and elongation capacity can be reduced by thermal and wet-drying cycling. Under such}

circumstances, adhesion and failure criteria can be determined as specified in EN 12618-1. Test specimens as specified in EN 12618-1 should be used. They should be submitted 24 thermal and wet-drying cycles according to EN 13687-3.