Masonry mortar
Advantages of Lime-Cement Mortar
Lime has been an essential component in construction for over 2000 years. The characteristics of slaked lime provide unique advantages in masonry, distinguishing lime-cement mortar from other building materials. It is the most commonly used mortar for laying concrete blocks, primarily due to its ease of use and cost-effectiveness.
The main advantages of lime-cement mortar for masonry include:
Tensile Strength
This refers to the strength of the mortar that holds masonry elements together. High tensile strength is guaranteed by the following characteristics of the mortar:
- Lime provides high water retention, allowing for early curing of cementitious materials.
- A significant initial flow that allows for easy coverage of masonry elements.
- Low air content in lime-cement mortar for bricklaying increases bonding strength.
Bonding Capacity
Bonding capacity is the percentage of a brick's surface area that the mortar adheres to. The low air content and fine particles of slaked lime increase the bonding capacity of the mortar with the bricks.
These factors allow lime-cement mortars to penetrate deeply into the bricks and seal the brick/lime boundary effectively. Using this mortar for laying cement blocks or bricks guarantees a quality and reliable construction that will endure for a long time, all at an affordable cost.
Water Flow
Studies show that lime-cement mortars can be used to minimize the potential for water penetration in masonry walls. The low air content, fine particle size, high plasticity, and water retention contribute to the excellent bonding strength of cementitious lime mortars. This eliminates easy migration paths for water penetration.
Autogenous Healing
When cracks appear in the mortar, slaked lime reacts with the carbon dioxide in the atmosphere. This reaction produces lime, which helps seal the crack and fill voids in the mortar. This explains the enhanced moisture resistance observed six months after curing in two studies.
Durability
Constructions created with this mortar system have low maintenance costs and are a durable system with proven performance. Using lime in the mortars contributes to the durability of the system. The high slaked lime content mortars improve the ability of the assembly to accommodate the stresses caused by building movement and temperature cycles without undue cracking.
Elasticity
Studies show that mortars with a high content of slaked lime cure slowly and remain elastic and flexible. Therefore, lime-cement mortars enhance the assembly's ability to withstand stresses caused by building movement and temperature changes without excessive cracking.
Proven Characteristics
Before the 1930s, all masonry structures were built using lime or a mixture of cement and lime. Lime was used as a primary ingredient in all mortars before this. The long-lasting durability of these structures serves as evidence of the lasting strength of lime-based mortars.
Slaked lime enhances the strength of the mortar through carbonation, cementitious reactions, and maintaining high pH levels in the mortar mix, making siliceous materials more soluble and reactive.