Types of Mortar

Types of Mortar

The mortar are classified on the bases of the following

1. Bulk density

2. Kinds of binding material

3. Nature of application

4. Special mortars

1. Bulk density:

According to bulk density of mortar in dry state, the mortars are two types

a. Heavy mortars bulk density is more than 1500kg/m3 and prepared from heavy quartz b. Lightweight mortars – bulk density is less than 1500/mg3 and prepared from light porous sands.

2. Kinds of binding Material

According to the kinds of binding material, several factors such as expected working conditions, hardening temperature, moisture conditions, etc should be considered. The mortars are classified into four categories.

a. Lime Mortar - in this motor, lime is used as binding material. Lime may be fate lime or Hydraulic lime. Fat lime mortar 1:2 to 1:3 and hydraulic lime mortarmay be1:2 by VOLUME.

b. Cement mortar: In this mortar, cement is used as binding material. Depending upon the strength required and importance of work, the proportion of cement to sand varies from 1:2 to 1:6 or more.

c. Gauged Mortar or composite mortar: The process of adding cement to lime mortar to improve the quality of lime mortar is known as gauging. It makes lime mortar economical, strong and dense. The usual proportion of cement to lime by volume is about 1:6 to 1:8

d. Gypsum mortar: These mortars are prepared from gypsum binding material such as building gypsum and anhydrite binding materials.

3 Nature of Application:

According to the nature of application, the mortars are classified into two categories.

A. Brick laying mortars: Mortars for brick laying are intended to be used for brick works and walls. Depending up on the working conditions and type of construction, the composition of masonry mortars with respect to the kind of binding materials is decided.

B. Finishing Mortars: these mortars include common plastering work and mortars for developing architectural or ornamental effects. Generally cement or lime is used as binding material.

4. Special Mortars:

a. Fire resistant mortars

b. Light weight mortars

c. Packing mortars

d. Sound absorbing mortars

e. X-ray shielding mortars

A. Fire resistant mortar- This mortar is prepared by adding 1:2 ratio of aluminous cement with crushed powder of fire bricks used for fire brick lining furnaces, fire places, ovens etc.

B. Light weight mortar – This mortar is prepared by adding sawdust, wood powder to lime or cement mortar for sound proof and heat proof construction

C. Packing Mortar – To pack of oil wells, special mortars possessing the properties of high homogeneity, water resistance, predetermined setting time, ability to form solid water proof plugs in cracks and voids of rocks, resistance to subsoil water pressure etc. have to be formed with cement

sand, cement loam and cement sand loam mortars.

D. Sound absorbing mortars: To reduce the noise level, sound absorbing mortars with Portland cement, lime, gypsum, slag Portland cement etc as the binding materials employed in its composition. The aggregates re selected from lightweight porous material such as pumice, cinders etc.

E. X-ray shielding mortar: This type of mortar is used for providing the plastering coat to walls and celling of x-ray cabinets. This is heavy mortar with bulk density over 2200kg/m3 is used. The aggregates are obtained from heavy rock and suitable admixture are added to enhance protective

property of such a mortar.