This is how you get a wrong answer from an engineer. StructuralBIMGGuy says
"Not from what I've seen in your photos..although you will need to look at the wall loading to say otherwise"
The correct answer is:
The mortar has been lab tested and has FAILED to COMPLY
The mortar also has failed to conform to the contract specification, it was supposed to be 1:1:6 cement, lime, sand but it was not.
Failure to comply = DEFECT
Failure to conform= BREACH OF CONTRACT
Defective mortar is unsafe and unacceptable.
And you don't need any calculations or the MUMBO JUMBO below:
You will need to provide evidence, calculations & proofs of tensile and bending Stresses, Failure, etc
The hand calculations are very complicated/difficult ..enter FEA/multiphysics software (Time based simulations) and there are now provisions for such in structural codes.
Here's what the battlers & Punters need to do
1. Get copies of all engineering specs,data,etc. Have the engineering independently inspected
2. Take photos of non compliance and future anticipated problem areas before they occur
3. Advise the builder of consequences of his failure to act, non-compliance and anticipated remedies
4.The evidence matches the simulations
5. It then becomes a Waiting game... There are lawyers & Engineers that specialise in such cases