The technical nature of the mortar

Mortar: The adhesive material used for masonry on the building. It is made up of a certain proportion of sand and cementing materials (cement, lime paste, clay, etc.). It is also called mortar and mortar. The mortar is made by mixing water with cementitious materials (cement, lime, clay, etc.) and fine aggregate (sand). Commonly used are cement mortar, mixed mortar (or cement lime mortar), lime mortar and clay mortar.

Technical nature

First, the workability of fresh mortar

The workability of mortar refers to whether mortar is easy to lay on the masonry and other surfaces into a uniform, continuous thin layer and is closely bonded to the base layer. Including the meaning of mobility and water retention.

(I) Liquidity

The factors influencing the fluidity of mortar are mainly the type and amount of cementitious materials, the amount of water used and the type of fine aggregate, the shape of the particles, the degree of thickness and the gradation, in addition to the mixed materials and admixtures incorporated. The variety and dosage are related.

Under normal circumstances, the substrate is a porous, water-absorbent material, or a mortar with a high fluidity should be selected when it is applied under dry heat conditions. On the other hand, if the substrate absorbs less water, or if it is constructed under wet and cold conditions, a mortar with low fluidity should be selected.

(two) water retention

Water retention refers to the ability of mortar to retain moisture. Poorly water-retaining mortar has bleeding and flow during use, which causes the mortar and the substrate to be loosely bonded, and the loss of water affects the normal adhesion hardening of the mortar, which reduces the strength of the mortar.

The main factors affecting the water retention of mortars are the type and amount of cementitious materials, sand type, fineness, and water consumption. In the mortar mixed with lime paste, fly ash and other powdery mixed materials, can improve the water retention of the mortar.

Second, the strength of hardened mortar

The factors affecting the strength of the mortar are: When the quality of the raw materials is constant, the strength of the mortar mainly depends on the cement number and the amount of cement. In addition, mortar strength is also related to sand, admixtures, blended materials, and masonry and curing conditions. When sand contains mud and other impurities, mortar strength is also affected.