Monument Future. Siegfried Siegesmund

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      Figure 1: Mortars samples at 180 days. The different formulations obtained are presented in Table 1.

      The first mortar prepared was the HFD after evaluation it was decided to increase the amount of the binder, to increase the resistance of 20 %. The mortars HS and AS are performed to compare binders, the mortar HB is prepared to test the additive, the mortar HSD is prepared to test the effect of granulometry to increase de resistance.

      The HSC and HSCR mortars start from the same base with 30 % of binder but one is prepared with water and the other with the pine resin solution, mortar HC was prepared to test the calcareous sand, and HSG for test the WPG.In future work more formulas will be prepared to make comparisons.

      Several properties have been measured in the harden mortars (90 or 180 days old). Porosity and density have been measured by the triple weight method following the standard EN 1936. Compressive and flexural strength were obtained in 4 × 4 × 16 cm³ samples, according to EN 1015-11 standard. Capillarity water absorption tests were performed following the standard EN 1015-18. Durability of the samples was estimated by salt crystallisation and frost resistance tests following standards EN 12371 and EN 12370. Dynamic Young’s modulus (E) and Poisson’s coefficient (n) from P and S wave velocities using the next equations (Baron 2007):

      In order to validate the obtained formulations, their physical properties have been compared with three commercial products (Altarpierre, Artopierre and Lithomex TM) previously studed in our laboratory and largely employed in France and others parts of the world.

       Results and Discussion

      Granulometry of the mortars produced in this work was compared to that of the commercial products to compare if it has an impact in the durability of the mortar. The particle diameter of all mortars ranges from 0.08 to 0.8 mm. Particle size distribution of mortar HB is a little different from the others due to the use of chamotte as aggregate. Mortar AS shows smaller particle size due to the use of air lime.

      Porosity and density, water capillarity absorption and relative amount of mixing water necessary to obtain the expected workability are presented in Table 2. The mean density measured at 90 days is 1,720(109) kg/m³, HSP mortar presents the smallest value with 1534 kg/m³ and the highest value corresponds to mortar HSG with 1,873 kg/m³. These two mortars have additives, pinecone and waste glass powder respectively, which shows that the use of the correct additives is able to modify 62the density of a restoration mortar. The mean porosity at 90 days is 33.7(4) %; HSG mortar, with 29.4 %, presents the lowest value and the highest value corresponds to HSP mortar, with 40.9 %. As expected, mortar with the lowest density has the highest porosity.

Table 1: Restoration mortar formulations in weigh percentage. WGP: Waste glass powder, PN: Pine cone, PCRS (Pine Cone Resin Solution), CHAM:Chamotte (Crushed brick waste).

      Figure 2: Granulometric Curves.

      The mean capillarity coefficient at 180 days is 1.73(0.53) kg/m²min^½, with a minimum of 0.99 kg/ m²min^½ for mortar HSP and a maximum of 2.57 Kg/ m²min^½ for mortar HB. These results are in accord with the results obtained by Margalha et al. (2011) in mortars with hot lime mix.

Table 2: Physical characteristics of mortars. ρ: density (kg/m³), n: open porosity (%), C: Capillarity coefficient (Kg/m²min^½), W: mixing water (g water/g dry mortar).

Mortar	ρ	n	C	W
HFD	1,783 (18)	30.2 (0.5)	2.39 (0.02)	0,16
HSD	1,713 (20)	31.2 (0.3)	2.02 (0.18)	0,18
HS	1,762 (13)	30.1 (0.2)	1.99 (0.02)	0,14
HB	1,541 (23)	37.9 (0.3)	2.57 (0.53)	0,27
HSCR	1,764 (8)	33.7 (0.8)	1.42 (0.20)	0,15
HSC	1,787 (26)	33.2 (0.2)	1.24 (0.45)	0,15
HSG	1,873 (26)	29.4 (0.1)	1.18 (0.1)	0,15
HSP	1,534 (14)	40.9 (0.1)	0.99 (0.1)	0,15
HC	1,669 (34)	38.4 (0.2)	1.97 (.13)	0,14
AS	1,771 (3)	СКАЧАТЬ В начало < 16 17 18 19 20 21 22 23 24 25 > В конец