Evaluations of different irregular conditions in bridges subjected to seismic load, considering systems with length relations of extreme girder to central girder of 1:0. 75 and 1:2, and structures with curvatures of 30o, 60o, 90o, 120o. Review of planning and construction services rendered in eleven projects (mostly road construction) in terms of quality and volume. By modernizing its street network, Gabon wants to promote the diversification of the country's economy, and further develop tourism and agriculture. This is also. This category has the following 2 subcategories, out of 2 total. There are times when engineers would have to design and evaluate bridge structures that fall outside of the AASHTO design guideline. Therefore, when do we define a structure as irregular? How is evaluating an irregular bridge different from evaluating a regular bridge? How to minimize errors during. In 2007, Tuojiang Bridge catastrophically collapsed during construction, resulting in 64 deaths and 22 injuries as well as a direct economic loss of about 39. Nevertheless, at present there is no developed road link to the inland. That's why the city can be reached or supplied only by air or sea so far.