Need a book? Engineering books recommendations...

Return to index: [Subject] [Thread] [Date] [Author]

Re: IBC Masonry Special Inspection Requirements

[Subject Prev][Subject Next][Thread Prev][Thread Next]
I agree that intermitent inspection for structural masonry should be defined
in the code.  I don't think individual engineers should define this inspection
for their jobs because there will be no standard and there will be different
kinds of inspections for different jobs. At least, the code should provide
guidelines for inspection if they will allow engineers to define it for each
job.

Let us go back to the history of Masonry Design. For working stress method of
design, we use half stresses and not require inspection.  When the slender
wall method of design first came out, They have two factors that can be used,
one for 'no inspection' required and another for 'inspection' required.  The
latest code does not allow the no inspection required anymore and all masonry
design using strength method has one factor only and inspection is always
required.

I believe the engineers responsible for the development of the latest Strength
Design formulas for slender walls, shear walls and momment frames shoud also
develop the guildelines for the extent of inspection required to attain the
quality of materials and construction method that they desired when they
developed these formulas.

Without these guidelines from the original formula developers, each engineer
will just have to use their individual judgement.

In my case, for a slender wall, I will require inspection only during the
grouting of the cells to insure that the rebars are in the correct position
during and after grouting.. I will also require that the inspector observe the
mason at the start of the job to make sure he applies the mortar at horizontal
joints properly and if he does, we assume that he will do it the same way the
rest of the job. Other engineers may not trust the mason that they will
require continuous inspection of the whole mortar laying process also. My
reason for this is because the moment strength of the wall is the most
important part of slender wall design and the position of the rebars is very
critical in determining the walls moment capacity. The quality of the mortar
is also important but second only to the rebar placement. A very small change
in the "d" distance of the rebar to the face of the compression side of the
wall will cause a very big change in moment capacity.

For walls with high shears or moment frames, I will require continuous
inspection. This is based on my thinking that all parts of the wall are
equally critical.

And like Tom said, all dowels, bolts, anchors and other inserts into the wall
will be inspected.

But like I said, it would be better if we get inspection guidelines or code
commentaries from the original formula developers.

Ernie Natividad