Author: haroonkhan

Causes Cracks are frequently found in brick masonry walls due to some of the reasons given below.

In an eccentrically loaded wall, there is an axial load and a bending moment. These two may be combined into a single resultant load acting at a distance. This is known as equivalent eccentricity (Fig. 17.15). Figure 17.15 Equivalent eccentricity The stress distribution due to axial load and the bending moment are combined to get the…

Figure 17.14 Eccentricity due to unequal span in interior wall

In general, walls in buildings are commonly loaded with some eccentricity. Eccentricity may be caused due to one reason or another. Thus, there is a little possibility of establishing an exact relationship between factors which may cause eccentricity. Some of the factors which contribute for eccentricity on brick walls are: Thus a designer has to…

Ordinary masonry walls are reinforced with iron bars or expanded metal mesh and such walls are called reinforced brick walls. Here, the reinforcement, iron bars or expanded metal mesh are provided at every third or fourth course (Fig. 17.11). Figure 17.11 Reinforcement of brick wall with metal mesh Alternately flat bars of sections about 25 mm…

Slenderness ratio is the ratio of effective height or effective length to effective thickness of the masonry unit. Slenderness ratio is an important factor to be considered in the stability of a wall. For solid walls, the effective thickness is the actual thickness of the wall. For the solid walls which are adequately bonded with…

Effective thickness of a wall is an idealised thickness which reflects the behaviour of the wall. Effective thickness is determined as detailed below. Table 17.4 Stiffness coefficient where Sp = Centre to centre spacing of pier or cross wall wp = Width of pier in the direction of the wall or the actual thickness of cross wall tp = Thickness…

While deciding the length of walls, the following end support conditions are considered: Various combinations of the above conditions and the effective length of a wall are presented in Table 17.3 (Fig. 17.10). Table 17.3 Effective length of walls Source: IS: 1905, 1987. Note: (i) H = actual height of wall between centre of cross wall/pier. L = length of…

If both lateral and rotational restraints are offered by a support, then the wall is said to be fully restrained at the support. It is said to be partial, if only lateral restraint is provided. Combination of these two restraint cases yields different boundary conditions depending on location. The effective height of a wall is…