Analysis On Stability Of Long Span Ribbed Slab Bridge System By Direct Lifting

With the development of highway construction and the improvement of the pre-stress technology and the maturity of direct lifting technology in our contrary, the pre-stress concrete T-beam has been more used by right of its properties such as making construction simplify and shortening working period, the T-bean is used everywhere and the span is more great. Thought the construction technology of pre-stress concrete T-beam is maturity, the accident of lost stability is familiar, analyzing on the accident and advancing prevented method is the important question in engineering.Combining the working status, this passage based the model of 50m T-beam by direct lifting; through the static and dynamic theory analysis, this passage analyze detailedly the status of loading by direct lifting, it include the study of static displacement, static stress, dynamic displacement, dynamic stress; besides, analysis of T-beam through Ansys. Finally, comparing theory analysis with Ansys analysis we can gained that the result leading the accident of lost stability is inertia coming from acceleration.Through the analysis of this passage, we should control the acceleration of 50m T-beam by direct lifting; also we must control the acceleration less than 0.5m/s2. Simultaneity, avoiding the upright acceleration and level acceleration happened at one time; preventing concrete crack by increasing the number of reinforcing. Finally, we can get a reasonable outcome through analysis and calculation; it has some importance to construction of direct lifting.