Code Name

Argentinean Standards for Earthquake Resistant Constructions

Issued by

Center of Investigation of National Regulations of Security for Civil Works

Revision

CONCAR70(1972), NAA80(1981), INPRES-CIRSOC103(1983), INPRES-CIRSOC103(1991)

Horizontal Base Shear

C: Seismic coefficient given by the following formula:

S_a: Seismic horizontal spectral value (See Fig 1)
γ_d: Seismic risk factor (See Table 1)

T: Fundamental period of the structure
a_s, b, T₁, T₂: Parameters (See Table 2)

For structures having a damping value smaller than 5%, the following S_a should be used:

f_A: Amplification factor due to damping calculated by following formula:

R: Reduction factor depending on the global structural ductility μ and its fundamental period T

μ: Global structural ductility (See Table 3)

W: Total weight of building given by the following formula:

W_i: weight at level i

Seismic Zone: (See Fig. 2, Table 4)

Building classification: (See Table 5)

Soil classification:

Dynamically Stable Soils

Type I (very firm and compact): Firm rocks or similar formations, and stiff soils above firm rock with a depth less than 50 m

Type II (soils with intermediate stiffness): Firm soils with a depth greater than 50 m or soils with intermediate characteristics of stiffness with a depth greater than 8 m

Type III (soft soils): Loose granular soils, soft and medium-stiff cohesive soils

Dynamically Unstable Soils

The Code assigns special measures for soils that could become unstable under a seismic load.