A COMPARATIVE STUDY OF MECHANICAL PROPERTIES AND DRYING SHRINKAGE OF MORTARS PREPARED WITH STANDARD AND RIVER SANDS AS A REPAIR MORTAR

作者：Pozo Antonio J S^*; Feijoo J

来源：Romanian Journal of Materials, 2016, 46(4): 471-479.

• Portland cement
• lime
• mortar
• aggregate
• curing
• Compressive strength
• Modulus of Elasticity
• Mechanical properties
• Drying shrinkage

Concrete lime-and NHL-based mortars were prepared with river sand and a standard ASTM sand as aggregate. The mortar samples were subjected to different curing conditions for 28 days in order to achieve the acceptable mortar strength in a shorter period of time, with the aim to move the repaired artworks from the restoration departments of museums while avoiding possible contamination or damages. The results are provided under the study of the influence of the curing conditions, the binder nature, the binder/aggregate ratio relation and the aggregate nature. The test results showed that ASTM sand was a good alternative to river sand; it even improved the mechanical characteristics and drying shrinkage of the NHL-based mortars and lime cement-based mortars. NHL5, with a lower amount of aggregates, achieved higher values of flexural tensile and compressive strength and performed mortars with lower shrinkage values, being the ASTM sand the aggregate that provided better properties. Synthetically, the lime based mortar NHL5 (1: 1.75) with ASTM sand under 14 days at a RH of 90 +/- 5% and 14 days at a RH of 60 +/- 5% seemed to be a satisfactory solution to be used as repair mortar in order to achieve good mechanical and physical properties without long periods in restoration departments.

• 出版日期2016