Reinforced concrete jacketed Z-shaped column section – rcjzcs

This is a section frequently adopted for the modelling of Z-shaped columns that have been retrofitted by means of reinforced concrete jacketing (steel- or FRP-wrapping can be modelled using the existing RC sections). The possibility of defining different confinement levels for the internal (pre-existing) and the external (new) concrete materials is available.

Materials and Dimensions

Six different materials can be defined; external longitudinal reinforcement, internal longitudinal reinforcement, external transverse reinforcement, internal transverse reinforcement, concrete jacket, concrete core.

The required dimensions are as follows:

• Bottom flange width. The default value is 1 m
• Bottom flange thickness. The default value is 0.45 m
• Top flange width. The default value is 1 m
• Top flange thickness. The default value is 0.45 m
• Web height. The default value is 1.3 m
• Web thickness. The default value is 0.45 m
• Jacket thickness. The default value is 0.1 m
• Cover Thickness. The default value is 0.025 m

Reinforcement

Longitudinal reinforcement bars can be defined in two different ways:

1. by editing the reinforcement pattern;
2. by entering the respective area and sectional coordinates (the latter being defined in the local coordinate system of the section).

Further, the transverse reinforcement may be specified, in terms of the stirrups' diameters and legs, as well as the distance between them.

Important: Re-bar distance d3 is to be measured from the bottom of the section.

FRP Strengthening

FRP wraps may be assigned by selecting the FRP Wrap from a list of the most common products found in the internet, or by introducing user defined values.

Notes

1. The confined concrete region is automatically computed by the program using the R/C cover thickness.
2. All re-bars must be located within the confined concrete region.