Terracotta Hollow Block Walls

[JrStructuralEng]

Hi, I am trying to determine the bearing capacity of old 1920's terracotta hollow block walls (See attached photo). The wall is approx 8.5" wide. We are installing windows lintels which will put point loads on either side and I am concerned about crushing the block.

 

[JrStructuralEng]

I should mention...(because someone is bound to say "Core-fill") that the flutes run horizontally in a similar fashion to the blocks shown in the photo. So core-filling is not possible.

 

[ishvaaag]

According to the attached recension, compressive design strength to be compared with factored stress (slendernesses taken unto account) is 10 kgf/cm2, or around 1 MPa, on total or brute section. With that design strength one had to operate till 2005 in Spain. It is clear that crushing strenght with no slenderness effects present was expected to be far higher than that.

Note that tile masonry suffers degradation and can be almost spoiled after say 100 years on bad exposures. Your photo example seems sound yet apparently porous and hence somewhat susceptible to damage brought by water.

 

[concretemasonry]

Horizontal cores have been common for over 100 years.

Are you concerned with the bearing capacity or the compressive strength? Unless the loads are high, the vertical steel on the sides of an opening is really for continuity since the natural distribution may govern. The vertical load is distributed on a 45 or 30 degree angle from the center of bearing. Longer lintels will spread out the load into the wall quicker.

Dick

Engineer and international traveler interested in construction techniques, problems and proper design.

 

[JrStructuralEng]

im concerned with bearing and compressive strength. ishvaag i'm not sure I understand your attachment.