PSI - Issue 5

Aalil Issam et al. / Procedia Structural Integrity 5 (2017) 1123–1128 Aalil Issam/ Structural Integrity Procedia 00 (2017) 000 – 000

1125

3

b

a

Fig. 2. (a) collapsed wall built with mud based mortar; (b) the use of Portland cement mortar.

2. Materials and methodology

2.1. Calcarenite stone

Calcarenite stone is a beige-yellowish calcarenite limestone (fig.3a), rich in terrigenous material and large bioclasts (Dessandier et al. 2008). It is the predominant stone on the site of Volubilis and represents about 60% of its building stones. Mineralogical analysis with XRD showed that this stone is mainly composed of calcite with some quartz (Aalil et al., 2016). Calcarenite blocks were extracted from the main original quarry at Ain Schkor. Eight cubic samples measuring 50 mm per side were prepared, using a diamond saw, for all tests except the compressive strength (CS) test which was conducted on 3 cylindrical samples (Φ40mm x80 mm). Mortars were formulated using aerial lime and regional materials: brick dust and washed dolomitic sand. The brick dust was crushed by a LOS ANGLES apparatus and then sieved through a 315 µm sieve. The regional sand was washed several times in order to reduce its salt contents and then dried. It has a continuous grading from 0.063 to 2 mm. In order to study the effects of each compound, nine mortars were formulated (table 1). Preliminary consistency tests determined the amount of water required for each formulation to obtain a good workable consistency. The prepared pastes were cast in prismatic 40x40x160 mm molds for 7 days and then placed in laboratory conditions. 2.2. Mortar formulation

Table 1. Mortar mixes: identification and weight contents of components. M 1 M 2 M 3 M 4

M 5 25.0 40.0 35.0 31.3

M 6 25.0 75.0

M 7 40.0

M 8 40.0 32.5 27.5 41.3

M 9 40.0 60.0

Lime (%)

10.0

10.0 47.5 42.5 22.7

10.0 90.0

25.0

Brick dust (%)

5.0

5.0

5.0

Sand (%)

85.0 18.7

0.0

70.0 26.3

0.0

55.0 36.0

0.0

Water / dry mixture (%)

31.3

37.3

47.5

2.3. Laboratory tests Porosity P(%), bulk density ρb and solid matrix density ρs were determined using the hydrostatic weighing method according to (RILEM 1980). The capillary water rise test was carried out on dried samples by following the procedure described in the EN 1925 standard (fig.3b). The capillary absorption coefficient A and the saturation coefficient reached at the end of the test were determined.