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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