BUILDING & MANAGEMENT VOLUME 3 ISSUE 2 MAY - AUGUST 2019
DECLARATION OF PERFORMANCE ( DOP ) AND CE MARKING OF CEMENT MORTARS MADE WITH RECYCLED STEEL WASTE
I . SANTAMARÍA-VICARIO , S . GUTIÉRREZ-GONZÁLEZ , V . CALDERÓN-CARPINTERO AND A . RODRÍGUEZ-SAIZ ( 2019 ). BUILDING & MANAGEMENT , 3 ( 2 ): 06-15
filtrate was acidified by adding 20 ml of diluted nitric acid ( 1 + 2 ) and brought to boiling point .
By means of a pipette ; 5 ml of the solution of silver nitrate 0.10 mol / l was added to the acidified solution . It was immediately brought to boiling point for 1.5-2 min ; and left to cool to a temperature below 25 º C . The contents of the beaker were passed to a 500 ml Erlenmeyer flask . 5 drops of the indicator solution of ammonium sulphate and iron III [ NH4Fe ( SO4 ) 2 · 12H2O ] are added .
A 10 ml burette is filled with an ammonium thiocyanate solution . The solution of the burette in the previous mixture is added ; turning a light brownish-red colour ; which disappears under vigorous agitation . The test ends when the colour is remained visible following agitation ( Fig . 3 ). The volume ; V1 ; of the solution of ammonium thiocyanate solution consumed in the assay was noted .
To do so , the procedure described in EN 1052-3 [ 22 ] was followed . The sample specimens consisted of three bricks with mortar bonds placed on a larger surface , as shown in Fig 4 . Double hollow bricks with dimensions of ( 240x110x90 ) mm and with a water absorption coefficient to saturation of 18 % were used .
To prepare the sample specimens , three ceramic bricks , previously dried in an oven , were placed in water for 1 min . Within that time , the bricks had absorbed 9 % of water , so that they presented a known humidity level that had not reached saturation point , but that avoided absorbing the mortar mixing water .
The previous procedure was repeated without the mortar sample and the volume ; V2 ; of the solution of ammonium thiocyanate necessary for this assay was noted .
The content of chloride ions ; expressed by mass % in reference to the sample of dry mortar was calculated by means of the following equation :
3.545 Cl( I)% = ( V2 −V1)
� f � 10� m
( 1 )
Where :
V1 is the volume of the ammonium thiocyanate solution ; 0.1M ( ml ); consumed during the assay of the test solution .
V2 is the volume of the ammonium thiocyanate solution ; 0.1M ( ml ); consumed in the dummy assay .
m is the mass of the test sample ( gr )
f is the molarity factor in relation to the solution of ammonium thiocyanate ( usually 0.10 mol / l )
Figure 3 . Operating procedure . Calculation of the water-soluble chloride content .
6.2 . DETERMINATION OF SHEAR STRENGTH
CE-markings of the masonry mortars that will be employed for masonry walls need to include the characteristic shear strength .
Figure 4 . Operating procedure . Preparation and breakage of sample specimens under shear stress
Having prepared the samples , they were placed in a polyethylene bag and compressed , with a mass uniformly distributed , to give a vertical tension of between 2x10 -3 N / mm 2 and 5x10 -3 N / mm 2 , in accordance with the specifications of the harmonized standard . The specimens remained unaltered over a period of 28 days in a humid chamber , under a constant temperature of 20 º C and a relative humidity of 95 %. At the end of the curing period , the specimens were tested in a Suzpecar model MEn 101 multitest machine , with a load capacity of 20 tn . ‘ Procedure B ’, detailed in the standard and shown in Fig 4 was followed .
The initial shear stress , fvoi , was calculated with the following expression ( 2 ): f voi = F i
2A i
( 2 )
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