Fundamental Frequencies of Vibration of Footbridges in Portugal: From In Situ Measurements to Numerical Modelling

Table 6

Peak acceleration amplitudes for different tests.

Walking load	𝑎max (mg)
	Vertical	Longitudinal	Transversal
1 Person*—walk at 𝑓=1.8 Hz	18.9	2.7	3.8
1 Person—walk at 𝑓=2.2 Hz	29.1	5.2	6.1
1 Person—jogging at 𝑓=2.5 Hz	38.2	20.2^#	12.1
1 Person—jogging at 𝑓=3.3 Hz	251.3^†	16.5	21.4^#
1 Person—jogging at 𝑓=3.7 Hz	252.6^†	12.5	24.5^#
2 Person—walk at 𝑓=1.7 Hz	26.3	6.4	5.8
2 Person—walk at 𝑓=2.1 Hz	38.3	25.3^#	7.0
2 Person—jogging at 𝑓=2.25 Hz	74.4^‡	28.9^#	19.0
3 Person—walk at 𝑓=2.1 Hz	71.5^‡	29.1^#	14.1
7 or 8 kids (30 to 40 kg)—slow walk	16.3	6.2	10.3
Noise	6.8	0.9	2.6
Jump	198.1^†	21.1^#	83.4^#
Excitation in transversal direction (resonance)	27.9	3.2	15.5
Impulse in transversal direction	39.8	3.8	17.0
Excitation in vertical direction (resonance)	239.2^†	11.7	16.1

∗74 kg.
^†Values of vertical accelerations exceeding the less stringent limit (93.8 mg); ^‡the most stringent limit (66.7 mg); ^#values exceeding the code ones for horizontal vibrations (20 mg, EN 1990 [20]).