Shear Strength Of Concrete Block Wall

In the case of masonry structures subjected to seismic loads shear failure mechanism of walls characterised by the formation of diagonal cracks by far predominates the sliding shear failure.

Shear strength of concrete block wall. Nominal axial and flexural strength nominal shear strength 9 3 5 wall design for out of plane loads 9 3 6 wall design for in plane loads. 11 can be referred to for determining strength of dry stack units. 3 clear rather than the designed 2 clear. The shear strength of masonry triplets was mainly determined by the failure of hollow concrete block unit.

In stiffeners and boundary elements spwallcalculates the required shear and torsion steel reinforcement. Shear wall concrete strength in plane and out of plane is calculated for the applied loads and compared with the code permissible shear capacity. Such a block 9 inches high weighs 130 pounds. Assuming a strength of 1 000 pounds and a factor of safety of 5 the safe load would be 200 pounds per square inch or 200 x 192 38 400 pounds for the whole surface of the block.

By applying weight functions to put different failures together in a failure zone the shear strength of concrete hollow block masonry under combined shear and compression loading which including three typical failures is presented. Increase in the shear strength of the wall with a further inc rease to 44 when the axial stress. Bending strengthof the section has been reduced by about 15 shear strengthat wall base has been reduced by about 14. 27 58 mpa standard methods of sampling and testing concrete masonry units ref.

6 provides typical values for the net moment of inertia i n and cross sectional area a n for various wall sections if the value of the bending stress f b given by equation 1 is positive the masonry section is controlled by tension and the limiting values of table 1 must be satisfied. Tek 14 1b section properties of concrete masonry walls ref. The maximum shear strength of masonry triplets with precast concrete anti shear blocks was 234 48 percent higher than that of the control specimens. Shear strength reduced from 7654 lbs to 6589 lbs.

For the plain walls the increase in axia l stress from 2 mpa to 3 mpa resulted in a 29. 3500 psi concrete 5 10.