Has anyone considered the effects of fiber/fibre on freeze/thaw resistance of concrete?
Dick
Engineer and international traveler interested in construction techniques, problems and proper design.
I worked at the Santa Susana site for 2 year from 7/1/1963 to7/1/1965. This was before the development of the Semi Valley.
I was employed by Rocketdyne (another division of north American Aviation) that used the vast majority of the area because of the area required for testing of liquid...
It is possible that those are not "earthquakes", but just "tremors" as the the relaxing of the rock. I worked in the Santa Susanna area and at Edwards AFB where our company tested rocket engines (150,000# thrust to 1.500,000# thrust). We had sensors at our "block-houses" where we had the...
Abuh -
How are you measuring the "strength of the masonry".
Most codes recognize the f'm, which is determined by testing of a prism consisting of masonry units and mortar. Masonry for code development is usually determined by testing wall sections (vertically loaded, shear and flexure) to...
It is only a "proclamation" for the press to create headlines or news items for the 10:00 o'clock news.
It will only be a legal document until is made a requirement/law with definitions and limits that provide something enforceable.
His mode is to provide a direction/impetus for law makers to...
That looks strangely like many buildings I have seen around the world. - In those the concrete frame is built just before the (or with) the masonry infill.
Hamza41: The in-fill units are adequate for the loads they see. The actual strength of the CMUs would be in the range of 3000 psi to 8500...
Minimums and local practices can exceed the "standard Class A (3000 psi)concrete" that is "adequate".
In some areas, for driveways, aprons, garage floors and some sidewalks, the unwritten standard is 4000 psi with 5% air for durability. Even if it is not written, a supplier may refuse to...
It is really not a special size unit, but a very common split block for veneer applications across the country.
Nominal length of 8" and a nominal thickness of 4". A guess would be 2-1/4" high since that is a common height for masonry veneers.
Dick
Engineer and international traveler...
If you are not adding additional loads, I don't see a reason/excuse for trying to tie the blocks together. I assume the block is laid in traditional running bond, which provide continuity, so the masonry acts as a structural panel.
Using a solid or filled top(semi-solid)has been common.
How...
2,000,000# and 10 seconds sounds like a launch of the recent rockets. I only saw a couple of firings.
On the ground in FLA you will likely have a good amount of moisture in the concrete. Our tests were on a rush 24/7/365, so the concrete never dried out and that is the reason for water cooled...
LeonardEulere -
What is the duration of the firing and what is the thrust of the rocket?
I worked in the facilities division of a rocket engine manufacturer. We had engines from 180,000# to 1,500,000# of thrust vertical downward and a firing duration from 30 seconds to 7 minutes. In most...
Aidan -
More information is needed.
In your area, what does "UB" refer to?
What codes are you referring to?
Is the 6" wall load bearing or just a non-bearing facade.
What is the shape of the block for the first course of the 140 mm wall wythe? I am sure there is some minimal vertical steel...
Jim's book and pilaster details were based around southern California products and shapes commonly used there.
The NCMA handbook is very good, but shows a number of methods used in different regions.
I suggest looking at local brochures to see what is available there near the construction...
I bought a home that was 75' long (50' house and 25' of garage footings 4' deep). It intersected a natural drainage pattern adjacent to golf course that was under construction. I had landscaping, AC, deck and a patio around the basement, so no work could be done on the exterior.
The next...
shuff -
Those certainly look like some older CMU shapes that are far beyond the ASTM minimal requirements. I would suggest to look at the ACI 530 requirements. The NCMA TEK notes also provide a good reference. When we wrote the design codes that led to the current codes and standards(ASTM...
There is a difference between a composite wall and a cavity wall with rigid foam in the cavity.
If you use an "eye and pintel" system, the exterior wythe sees different conditions than the interior (temperature/moisture) and can perform well. The ties allow the differential lateral movement of...
The stresses in the fully grouted assembly are very small and distributed over a long period of time.
The "classic"/typical concerns about the different material properties are for the classic block/brick wall with the voids connected with wire. There is a limit is a limit on that type of...
That is definitely a composite wall that resists the load totally and not with the individual wythes.
The 2" grout is just like a collar joint. The 8' to 11" grout should be placed every 4' of height. As the grout consolidates, the excess grout moisture is sucked into the masonry units...
After searching my old memory banks, The best place to start would be Molin Concrete Products in Lino Lakes, MN.
They made Flexicore wet cast plank (16" and 24" widths) and also made some specialty shapes needed.
Dick
Engineer and international traveler interested in construction techniques...
Granular "A"??? What is the reference for the material?
What kind of pavers? - Larger flat or "brick size" interlocking pavers.
For the latter, the sand must be finer sand meeting the ASTM requirements. For this type of pavers, the pavers are placed tight on a 1" sand base and additional sand...
