In the performance analysis of existing buildings, the fracture type of concrete elements is classified as ductile if bending and as brittle if shear. While controlling the ductility of concrete elements in linear performance analysis, it is classified as brittle if the shear force value taken as the basis is greater than the shear strength, and as ductile if the shear force value is less than the shear strength.


ECO = Impact / Capacity ratio
R a = Earthquake Load Reduction Coefficient
β v = Shear force dynamic magnification coefficient at the curtain
f ck = Concrete characteristic cylinder compressive strength
V e = Design shear force based on column, beam and curtain
V leg = Above the node point and The smaller of the column shear forces calculated according to Section 4 under

TBDY Section 15.5.2. Determination of Damage Types in Structural Elements of Reinforced Concrete Buildings - In determining the application limits of the following calculation methods for reinforced concrete systems, the numerical values ​​expressed as bending effect / capacity ratios (ECO) of the sections of beams, columns and curtain elements will be used. - Reinforced concrete elements are classified as "ductile" if the fracture type is bending, and "brittle" if shear.

(a) columns, beams and curtains ductile element the shear force calculated in accordance with the bending capacity at the critical sections of the element to be counted V e 's, 15.2 as defined in knowledge compatible with existing material strength using the values for Eq. (7.10) at it must meet the given limits. V e 's account for columns 7.3.7 ' to, for beams 7.4.5 'to e and curtains 7.6.6 "According to do, but Eq. (7.16) at β v = 1 shall be taken. V e in columns, beams and wallsIn the calculation of, instead of hardening bearing moment moments, bearing power moments will be used. Vertical loads with R a = 1 V on the total shear force calculated by the earthquake to the case to be less than V e instead of the shear force will be used.

(b) Reinforced concrete elements that do not meet the ductile element conditions given in (a ) above , shall be defined as fragile damaged elements . - The impact / capacity ratio (ECO) of ductile beam, column and wall sections is obtained by dividing the total section moment calculated by taking R a = 1 under the effect of gravity loads and earthquakes by the section moment capacity. The direction of the earthquake force applied in EKO calculation will be taken into account. The axial forces corresponding to the bending moment capacities of the column and wall sections will be calculated under the combined effect of the vertical loads and earthquake loads calculated by taking R a = 4. - The impact / capacity ratio of reinforced partition walls is the ratio of the shear force calculated under the effect of an earthquake to the shear force strength. The shear forces generated in the reinforced partition walls modeled with diagonal bars will be considered as the horizontal component of the axial force of the bar. - In reinforced concrete column-beam joints , the shear forces acting on the joint for all boundary situations and calculated from Equation (7.11) should not exceed the shear strength given in . However, Eq. (7.11) from V leg instead 7.3.7 according calculated without concern to hardening V e to be used, Equation (7.12) or Eq. (7.13) 'is wherein the strength calculations f ck instead of 2.15Current concrete strength determined according to the knowledge level defined in. If the joint shear demand exceeds the shear strength, the column-beam junction area will be defined as a brittle damaged element.

Next Topic

Related Topics