Effects of carbonation on the pore structure of non-hydraulic lime mortars

In recent years, the use of hydraulic lime in conservation and restoration of historic buildings has increased due to the pathological processes involved in the use of Portland cement. This investigation determines the properties of hydraulic lime mortars with added carbon fibers for their possible use in restoration of architectural heritage. The results obtained are compared with mortars to which glass and basalt fibers have been added. The results show that the fibers affect significantly the behaviour of the mortar. Although the fibers have a negative impact in the workability and increase the air void content, they improve significantly the mechanical strengths. Although no relevant differences have been found in the pre-cracking behaviour, it has been proven that the fibers avoid a fragile behaviour of the mortar, showing a better post-cracking behaviour. Mortars with carbon fibers are the ones that show the best performance, increasing the toughness up to 12080% over the reference mortars.

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Natural hydraulic lime versus cement for blended lime mortars for restoration works

Construction and Building Materials ◽

10.1016/j.conbuildmat.2015.06.058 ◽

2015 ◽

Vol 94 ◽

pp. 346-360 ◽

Cited By ~ 49

Author(s):

B.A. Silva ◽

A.P. Ferreira Pinto ◽

A. Gomes

Keyword(s):

Hydraulic Lime ◽

Natural Hydraulic Lime ◽

Lime Mortars

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Design and evaluation of restoration mortars for historic masonry using traditional materials and production techniques

MRS Proceedings ◽

10.1557/proc-712-ii2.7 ◽

2002 ◽

Vol 712 ◽

Author(s):

Antonia Moropoulou ◽

Asterios Bakolas ◽

Petros Moundoulas ◽

Eleni Aggelakopoulou ◽

Sofia Anagnostopoulou

Keyword(s):

Mechanical Strength ◽

Water Absorption ◽

Mechanical Tests ◽

Hydraulic Lime ◽

Historic Masonry ◽

Natural Hydraulic Lime ◽

Total Percentage ◽

Lime Mortars ◽

Production Techniques ◽

Absorption Measurements

ABSTRACTCement based mortars used for historic masonry restoration presented unsatisfactory results, due to their chemical and physico-mechanical incompatibility to original buildings. In the present research, several syntheses of restoration mortars are produced using traditional techniques and materials such as binders (aerial and natural hydraulic lime), pozzolanicadditives (natural and artificial pozzolanas) and aggregates (sand and crushed brick). The technical characteristics of the mortars were determined using mechanical tests (compressive and flexural) and mercury intrusion porosimetry measurements at the time of 1, 3, 9, 15 months of curing. Water absorption measurements were performed at the time of 9 and 15 months curing, in order to evaluate mortars microstructural characteristics, their rate of water absorption and the total percentage of absorbed water. The aerial lime - artificial pozzolana mortar presented the best mechanical and microstructural performance. Hydraulic mortars acquired the maximum of the mechanical strength in 1 month, lime - pozzolana mortars in 3 months while aerial lime mortars continue to gain mechanical strength even in 15 months curing. Furthermore, the use of ceramic aggregates produces lightweight and elastic mortars, compatible to historicones.

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