Interval Threshold Setting Method of Vertical Support Reaction for Early Warning of Concrete Bridges

Abstract:

Existing bridge health monitoring systems neglect the benefit of support reaction index for the safeguard of bridge safety and generally do not include the monitoring of support reaction values. The basic setting method of vertical support reaction threshold was proposed in this paper. For concrete bridges, which have prominent discreteness, statistical analysis method should be employed to obtain the representative value of the modulus of elasticity. However, in practice, it is very difficult to obtain large amounts of data sample. The small sample analysis is necessary, with intent to reduce the uncertainty. For this purpose, t -distribution was introduced to carry out interval estimation for the mean value of modulus of elasticity. Confidence interval can be obtained and then be used as the representative value of modulus of elasticity. By adopting each endpoint of this interval respectively, two sets of vertical support reaction values under the most unfavorable load combination can be obtained and then multiplied by a reduction factor. For each bearing, there are two corresponding values, which can be used as boundary values and then interval threshold of vertical support reaction for concrete bridges early warning can be obtained. Finally, multiple level early warning based on the interval threshold can be actualized.

• Periodical: Applied Mechanics and Materials (Volumes 638-640)
• Pages: 1049-1054
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.638-640.1049
• Online since: September 2014
• Authors: Zhong Jun Ma*, Sen Sen Li
• Keywords: Bridge, Early Warning, Monitor, Support Reaction

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