Thermal Interaction of a Geosynthetic Reinforced Soil Integrated Bridge System in St. Lawrence County, NY

摘要

The geosynthetic reinforced soil integrated bridge system (GRS-IBS) can be used to support a variety of superstructures for single span bridges. The technology appears to demonstrate compatibility between the substructure and the superstructure, requiring no special design details to maintain serviceability of the approach due to lateral movement induced by thermal expansion and contraction of the bridge. This paper presents the behavior of the lateral abutment face movement in combination with the corresponding back wall pressures at the interface between the bridge and the approach of a GRS-IBS built along CR47 in St. Lawrence County, NY in 2013. The 32 m long, single span GRS-IBS, with a 3.7% superelevation and 30 degree skew, was instrumented to monitor the thermally induced movement of the abutment wall face in combination with lateral backwall pressures to evaluate the response of this particular superstructure geometry for the IBS. During the initial eight month monitoring period, the data shows both the GRS abutment and superstructure moved in unison with the seasonal change in temperature. In addition, the passive pressures induced from the thermal expansion of the superstructure are minor, and similar to those seen in an IBS with no skew.