Aiming at the anti-collision performance of SS-grade concrete guardrail of Chinese highway bridges, the nonlinear dynamic simulation of collision is carried out. On this basis, aiming at the defects of rigid guardrail, a rigid and flexible composite double-layer guardrail is proposed, and its anti-collision performance is evaluated. The vehicle factor analysis shows that the energy absorbed by the guardrail system, crash force, guardrail damage and reinforcement stress range increase with the increase of vehicle speed and impact angle. The effect of concrete grade on improving the anti-collision performance of guardrails is limited. It is not that the higher the strength grade, the better the effect. Compared with concrete guardrail, the vehicle deformation energy of double-layer guardrail system is only 59.1% of that of concrete guardrail system. This shows that the deformation of the vehicle is more serious when the vehicle hits the concrete guardrail, and the damage to the driver and passenger is greater, while the double-layer guardrail can improve the safety of the driver and passenger. The crash force of double-layer guardrail is reduced, so the impact suffered by passengers is reduced and the double-layer guardrail has good buffering effect.

The curved beam bridge exhibits lateral displacement during construction and operation. Taking a curved beam bridge as an example, the status of lateral displacement of the bridge is investigated in detail in this paper. To understand the mechanism of the curved beam lateral displacement, further to determine the curved beam lateral displacement under temperature effect, using ANSYS software to establish solid element model of the curved beam, steady state thermal analysis method is applied to analyze temperature field. Based on the analysis, the lateral displacement under temperature effect is analyzed. Then in order to further explain the lateral displacement mechanism, to discuss the frictional force causing the residual deformation of the rubber bearing to make the lateral displacement of the curved beam, the mechanical mechanism of curved beam under temperature effect is approximately analyzed. On the basis of clarifying the mechanism of lateral displacement, the paper puts forward the reinforcement measures for the curved beam bridge. In order to verify the treatment effect, long-term displacement monitoring is performed on the bridge. Numerical studies and monitoring data show that temperature is the main factor that causes the lateral displacement. Monitoring data over the past year shows that the displacement of the bearing is less than the value of allowable displacement after the reinforcement measures are adopted, and the bridge is in a safe state.