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
Where :
Fi is the shear stress ( N )
Ai is the transversal area of a sample parallel to the horizontal bonded joints ( mm 2 )
On the basis of these individual results , the average initial shear stress strength , fvo , was estimated .
The characteristic shear strength , fvok , was calculated according to the following expression ( 3 ):
Where :
fvo is the average initial shear strength ( N / mm 2 )
6.3 . THERMAL CONDUCTIVITY
The test for the determination of thermal conductivity followed the guidelines established in standard ASTM C 1114-06 [ 23 ]. To do so , 6 specimens of each mortar type were prepared with the following dimensions ( 110x70x6.5 ) mm 3 . The specimens remained in the humid chamber for 28 days .
A THASYS thermal conductivity Measurement System was employed , a machine that is based on a laminar heat transfer method , in accordance with the requirements of Annex 1 of the aforementioned ASTM , consisting of a thin heater apparatus THA01 and a measurement control unit MCU01 , from HUKSEFLUX THERMAL SENSORS .
It ran on a Thasys v0909 . CR1 data acquisition and control software version of the “ Campbell Scientific LoggerNet ”.
6.4 . FIRE RESISTANCE
f vok = 0.8xf vo ( 3 )
Cylindrical samples with a diameter of 75 mm and a height of 150 mm were prepared to classify the behaviour of the mortars when exposed to fire . These specimens were cured in a humid chamber for 28 days at a temperature of 20 º C and a relative humidity of 95 %. temperature of the oven throughout its central axis , the persistence of flames ( sec .) and mass loss (%) were all recorded .
7 . RESULTS AND DISCUSSION
7.1 . WATER-SOLUBLE CHLORIDE CONTENT
The results for each of the test samples and the average for each mortar type appear in Table 4 .
Water-soluble chloride content (%) MSwr
Standard EN 998-2 [ 11 ] indicates that the mortar manufacturer must declare the chloride content . This value must not be greater than the declared content and must never exceed 0.1 % in relation to the mass of dry mortar .
The mortars in this study presented a lower content than the standard specification , which was expressed in the data sheet specifications : Content of chloride ions < 0.01 %.
7.2 . DETERMINATION OF SHEAR STRENGTH
MSap Sample 1 0.005 0.007 Sample 2 0.007 0.005 Average 0.006 0.006 Table 4 . Water soluble chloride content in relation to the mass of dry mortar .
In Fig 5 , the breaking load under shear stress , Fi ( kN ), of the test samples is shown as a function of displacement in the test machine . The construction specimen formed by the three bricks and mortar bonds presented an initial breakage point in the brick . Nevertheless , the specimens were sufficiently strong to support a higher shear load , up until complete breakage . The value of the breaking load that was registered was the first breakage value . The average values from the test are shown in Table 5 .
The non-combustibility test was completed as described in standard EN ISO 1182 [ 24 ]. The specimens were conditioned for 72 h at a temperature of 23 ± 2 º C and a humidity of 50 ± 5 %. They were then dried in a ventilated oven at a temperature held at 60 ± 5 º C for 24 h .
The samples were introduced in an oven equipped with thermocouples for temperature control , and the oven temperature was increased at a constant speed that was stabilized for at least 10 min at 750 ± 5 º C .
The test was stopped when the equilibrium temperature was reached or after 60 min had elapsed . The increased
Figure 5 . Breaking load under shear stress ( kN )
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