ESWWR Vs Conventional steel reinforcing. 1

[yjung]

Hi all,

I have a question on using ESWWR (Engineered structural welded wire reinforcement).

I have #5@12" reinforcement specified on the plan.
Someone wants to use ESWWR by finding equivalent area of steel and spacing. Does it really work? If they can weld the between bars why they need to provide lab-splice?

is the conversion factor simpliy the linear relationship between the rebars and ESWWR ? The linear relationship between the conversion factor is somewhat strange because of the welded and tied bars connection.

What do you think about this ?

thanks always,

 

[RiBeneke]

I think you will get better answers if you ask your question on the 'Concrete Engineering' part of the Forum.

There are a number of issues
1) Tensile capacity is related to the total cross-sectional area of steel in each direction and the specified yield strength. The effect that welding has on the yield strength is not normally taken into account directly.
2) Bond strength is different depending on the surface texture of the bars, and is also affected by the welded cross-bars of the fabric (mesh).

 

[yjung]

do you know any reference for your first comment?
regarding "the effect that welding has on the yield strength is not normally taken into account directly."

please let me know.

thanks

 

[RiBeneke]

In the codes of practice for concrete design that I have seen, the properties of the cross-section, for the steel tension side, are based on cross-sectional area of steel and nominal characteristic yield strength of the steel bars or wires.
The characteristic strength may include some allowance for the effect of welding, but I have never seen this mentioned. A material factor (say 0.87) accounts for variability in strength in all cases, and is not necessarily related to welding effects.
Normally a beam in bending will have the bending resistance governed by both concrete compressive strength on one side of the member and steel tensile strength on the other side of the member.