Analysis of 100 yr old Granite masonry
Analysis of 100 yr old Granite masonry
(OP)
Does anyone have any experience analyzing a 100 year old masonry wall built of large granite boulders? If so, what documentation did you find for allowable stresses?
How about the mortar, does anyone have a good reference for determining the allowable stress in the mortar for what was common at that time?
How about the mortar, does anyone have a good reference for determining the allowable stress in the mortar for what was common at that time?






RE: Analysis of 100 yr old Granite masonry
The mortar will have to be analysed. Master masons of a century ago had to source their own hydraulic materials. Check Sliderules website for some information on historic masonry.
Dik
RE: Analysis of 100 yr old Granite masonry
I am trying to convince the owner he needs to have it analyzed but so far unsuccessfully.
Thanks for the website, I will check it out.
RE: Analysis of 100 yr old Granite masonry
For cut granite limit (squashing without buckling) compressive strength is 40 to 80 kgf/cm2
Divide by your safety load factor to get your allowable, say 1.6 or 2.
RE: Analysis of 100 yr old Granite masonry
For stone walls, I would look to a SF of approx 5 to 10...
Dik
RE: Analysis of 100 yr old Granite masonry
RE: Analysis of 100 yr old Granite masonry
RE: Analysis of 100 yr old Granite masonry
Dik
RE: Analysis of 100 yr old Granite masonry
Respect the safety factors, note that code piet 70 was already a model code on limit strengths, and the design (characteristical) strengths above are values expected to be stood say 95% of the times. So the statements of the (limit) design crushing strengths above may not be in big disaccord with dik view of safety factors on the 5 to 10 order IF on average crushing strength (not the characteristical value).
So in my view, if normally one would use the 1.7 safety factor with the values above of characteristical design strength on the section once the buckling effects have been added, the main remaining question is to what extent we must increase the safety factor over such 1.7 to account for mortar degradation, an issue that can only reasonably be approached by direct investigation of its current state.