Dimensional Limit Conditions for Polygonal Cross-Section Shearwalls
- oğuzcan hadim
- Zeynep Aladağ
The axial pressure force control calculated under the joint effect of vertical loads and earthquake loads is done automatically A c ≥ N dm / (0.35 f ck ).
It is controlled automatically that the ratio of polygon curtains to the thickness of the long side in the plan is at least six.
The control that the curtain thickness in the body area of rectangular and U, L and T curtains is not less than 1/16 of the floor height and 250 mm is automatically checked and the user is warned.
ICONS
A c = Gross cross-sectional area of the column or curtain end zone
ΣA g = The sum of the cross-sectional areas of the
structural system elements operating as a curtain parallel to the earthquake direction considered at any floor ΣA p = Total of the plan areas of all floors of the building
E = Earthquake effect
f ctd = Concrete design tensile strength
f ck = characteristic cylinder compressive strength of concrete
G = constant load effect
N dm =The largest of the axial pressure forces calculated under the joint effect of vertical loads and earthquake loads (taking into account the live load reduction coefficients defined for live loads in TS 498)
Q = Live load effect
V t = Total earthquake load acting on the building according to Section 4 (base shear force)
Cross-section Conditions Provided for Polygon Curtains
According to TBDY 7.6.1 , these following cross-section conditions are valid for polygonal walls other than basement walls. These cross-sectional conditions are not valid for basement curtains.
TBDY Article 7.6.1.1 according to vertical loads ( G, Q ) and seismic loads ( E ) under the joint effect ( G + Q + E ) is the largest of the calculated axial force N dm , curtain gross cross-sectional area A c and concrete characteristic pressure The condition given below must be met , with its resistance f ck .
A c ≥ N dm / (0.35f ck )
An example Curtain Group Axial Force Control Report is shown below. As seen in the picture, all parameters of the 7.6.1.1 condition are given and control has been made.
According to Article 7.6.1.2 of TBDY, the ratio of the long side of the walls in the plan to the thickness should be at least six. At the same time , conditions regarding wall thickness are given in 7.6.1.2 (a), (b) and (c) .
(a) Except for the special cases specified in 7.6.1.3 , the wall thickness in the body area of rectangular and U, L and T curtains shall not be less than 1/16 of the storey height and 250 mm.
(b) The thickness of the rectangular curtain or curtain arm shall not be less than 1/30 of the length of the curtain or the curtain arm that is not kept in the lateral direction in the plan.
(c) If the curtain arm is held at both ends by a curtain in lateral direction, the curtain arm thickness shall not be less than 1/20 of the floor height and 250 mm.
This situation is stated in both Getometry Controls and reports when modeling except the conditions given in Article 7.6.1.2 of TBDY . The image below shows a sample Getometry Control . In this control , it is seen that the conditions given in 7.6.1.2 are controlled.
According to the article 7.6.1.3 of TBDY , in the buildings where the load-bearing system consists of curtains, the polygon curtain arm thickness should not be less than 1/20 of the height of the highest floor in the building and 200 mm in cases where both conditions given in Equation 7.14 are met.
Requirements for the control of 7.6.1.2 and 7.6.1.3 are given in the Curtain Arm Thickness line under the Group Wall Dimension and Reinforcement Conditions heading of the Preliminary Information report of the Curtain Group . The picture below shows an example of the Curtain Group Preliminary Information report.