Dear Greg and Alimar,
The use of cables for tension members obviously intrigues engineers and has been intiguing me. You may have seen that there was another thread on this subject today.
Allow me a stupid question which is not so much structural but more language related. (English is not my...
Wire ropes have a lower modulus of elasticity than steel. It can be as low as 50% of the steel e-modulus. So one has to accept higher deflection, but I guess you (and the analysing software) knew this already.
Right. So one can say ceramic tile floors behave different from the concrete slab underneath. If the connection between tiles and concrete slab is rigid stress builds up that leads to the popping up.
What is it that causes the stress (contraction of concrete slab)? Is it temperature or/and...
Yes. I suspect shrinkage of the concrete slab. However, the building(s) are several years old.
We are talking about Cambodia which enjoys tropical climate with temperatures around 30 deg. Celsius year around. Night time temperatures drop sometimes below 20 deg. in January. There is a...
Has anybody seen ceramic floor tiles lifting off suddenly and got a good explaination for it?
The tiles are (were) directly mortared to a reinforced concrete slab. The lifting of tiles occured suddenly and created quite some noise. Apparently, the tile floor was under lateral stress and the...
Goncetra,
Thanks for the replay.
I think overfinishing is not the case as we are talking about walls that were not treated after the formwork was taken off.
If the unit detects only the P-wave and not the R-wave, would this in your opinion be an instrument issue? Or could this also be...
Many thanks for your replies.
The contractor had not only a problem with controlling the mixing plants. Placement, compaction and grout loss were issues, too. This is what kick off the investigation. I'm not supprise that we encounter concrete of different density and strength, even when the...
We sounded a few (12) concrete cores before they were cruhed in the lab. The scatter was that high that one could not see any relation between pulse velocity and concrete strength.
Yes, we think we follow the multiple measurement procedure. Could you have a look at the two files? We do four readings per location. We avoid rebars by locating them beforehand. The diagrams of the readings suggest that there are little hiccups in most locations.
From your link I figure that...
Thanks for the reply.
The difference is fairly consistent considering the scatter one has to expect for these readings. Please have a look at attached spread sheet. (I guess we do not have enough readings.) The sounding was done on concrete of different pours. The mix, however is supposed to be...
We are currently sounding concrete with a swiss-made ultrasonic instrument call TICO. Literature says that the pulse velocity for indirect or surface transmissio is 5 to 20% lower than the velocity of direct transmission.
In our tests we find the pulse velocity of indirect transmission 50 to...