The `Websol' system of soil reinforcement was used to construct the abutments to two bridges along a section of the Carmarthen bypass. This system utilizes a coated polyester strap for the soil reinforcement. The construction and performance of the west abutment of the rail bridge was selected for detailed study. Construction of the abutment commenced in July 1981 and the bypass was opened to traffic in July 1983. The report presents and discusses the data obtained from surveys of the structure up to June 1994. The data show that over the past ten years or so the centreline of the structure settled about 15mm but little or no movement occurred at the ends of the abutment. This increase in differential settlement has not led to any damage to the face of the structure. In June 1994 the maximum differential settlement along the abutment was equivalent to a gradient of about 1 in 95. There has been no significant change in the alignment of the face of the structure over the past decade and it can therefore be concluded that creep movements of the plastic reinforcements have been negligible. (A)
Samenvatting