Civil Engineering Reference
In-Depth Information
Since the observed changes in frequency and amplitude are more regular than the changes in temperature, it could be said
that the change in frequency is due to the effect of traffic on the bridge. This could be due to the direct effect of the increased
mass on the bridge; it is seen that the lowest frequency is during the day (and highest at night) which corresponds with the
concept of the greater mass during in the day lowering the fundamental frequency.
To examine this further, a more detailed study will be required to look at the effect of change in traffic throughout the day.
For example in the two rush hour periods where the bridge is heavily loaded with slow moving traffic, and then the midday
period where the bridge is heavily loaded with faster moving traffic. In addition the phenomenon will be studied using a
longer set of data, such as sets of 2 weeks of data each month for 6 months.
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