Column-Beam Joint Confinement Conditions (Confined and Unconfined Joints)
Column-beam joints in frame systems formed by columns and beams of high ductility level are automatically controlled as two classes (flanked joints and unconfined joints) as described in (a) and (b) below .
A s1 = Total area of the tensile reinforcement placed on one side of the column-beam node to accommodate the negative moment of the beam
A s2 = Thetotal area of the tensile reinforcement placedon the other side of thecolumn-beam node withrespectto A s1 to accommodate the positive moment of the beam
b j = the earthquake direction considered, if the beam stuck in the joint area is the same width as the column or protrudes from both sides of the column, the column width, otherwise, twice the distance from the vertical middle axis of the beam to the column edges (the beam width cannot exceed the sum of the height of the junction)
b w = Body width of beam
f ck = Characteristic cylinder compressive strength of concrete
f yk = Characteristic yield strength of longitudinal reinforcement
h = Cross-section dimension of the column in the direction of the earthquake
V e = Shear force taken as basis in the transverse reinforcement calculation in the column, beam, junction area and curtain
V arm = Above and below the node point Section 4 the smaller of the column shear forces calculated according to
Confined and Unconfined Joints
Column-beam connections in frame systems consisting of columns and beams of high ductility level are divided into two classes.
Confined Connection: Column-beam connection is classified asa confined joint if the beams are joined to the column from four sides and the width of each beam is not less than 3/4 of the column width.
Unconfined Union: All column-beam joints that do not satisfy the confined joint conditionare classified as unconfined joints .
TBDY Article 7.5.2 from which to calculate Column-Beam Shear Safety limit value to be used for calculating the design shear 7.5.1 from made confined joints and unconfined connection classification .
Confined joint conditions are shown in Figure 7.10 .
This classification is shown in the Column-Beam Junction Area Shear Safety report. The following picture shows an example of a report and the classification status made according to 7.5.1 .