Table 3 Default parameter values used in the simulations. Here, S.D. is the standard deviation of parameter mismatch among pedestrians, which follows a normal distribution in all cases.

a

Auxiliary

m

0.047

0

Ref. ^20,45

\({b}_{\min }\)

Margin of stability

m

0.0157

0.002

Ref. ¹⁸

C

Bridge damping

Ns/m

29,251

g

Acceleration of gravity

m/s⁻²

9.81

L

Effective leg length

m

1.17

0.092

Ref. ³¹

m

Pedestrian mass

kg

76.9

10

Ref. ³¹

M

Bridge mass

kg

113,000

Ref. ¹¹

p_c

Auxiliary

m

0.063

0

Ref. ^20,45

T_add

Pedestrian addition time

s

20

X₀

Unperturbed half step length

m

0.36

Ref. ^42,81

Y₀

Unperturbed half step width

m

0.047

Ref. ¹⁸

λ

Damping due to walking

s/m²

23.25

0

ω

Unperturbed angular

rad/s

5.655

0.1

Ref. ^20,42

Stride frequency

Ω

Angular bridge

rad/s

6.503

Ref. ^11,12

Natural frequency