IS 1893 Seismic Load Calculator

Dynamic analysis required (Cl. 7.7.1). This building is 21.0 m tall in Zone IV. The equivalent static base shear below is valid only as the lower-bound scaling target of Cl. 7.7.3 — where the dynamic base shear V_B′ is less than V_B, all response quantities from the dynamic analysis must be scaled by V_B/V_B′.

Ductile detailing to IS 13920 is a pre-condition for this R value.

Project information

Appears on the printed calculation sheet

Project Structure reference Prepared by Checked by Date Revision

Site location & seismic zone

IS 1893 Annex E · Table 3 · Table 7

Town / city (Annex E)

Annex E → Zone IVZone override A town on a zone boundary line is taken in the higher zone. For any town not listed, read the zone from Fig. 1 of the standard.

Zone

0.24

ρ (%)

1.6

Z/2 (DBE)

0.120

Soil classification

Spectrum soil (Table 4) and foundation soil (Table 2) are independent inputs

Soil type for spectrum (Cl. 6.4.2.1)Type I: rock/hard soil, N > 30 · Type II: medium/stiff, N = 10–30 · Type III: soft soil, N < 10Foundation soil type (Cl. 6.3.5.2) Site is liquefiable N < 15 (Zones III–V) / N < 10 (Zone II)

T₁ (s)

0.55

1.36

Sa/g floor

0.34

Bearing increase

25%

Damping

5% (Cl. 7.2.4)

Occupancy, structural system & analysis

Table 8 · Table 9 · Cl. 7.7

Occupancy (Table 8)Importance override (≥ table value) (Cl. 7.2.3)

Lateral load resisting system (Table 9)Analysis method (Cl. 7.6 / 7.7) Frame has masonry infill Include vertical component (Cl. 6.4.6)

1.20

5.0

R / I

4.1667

Participation

0.3