The Performance Assessment of a Precast, Panel-Segmented Arch Bridge with Outriggers

Abstract

Stone arch bridges, which are globally implemented, are advantageous with respect to material strength and durability. To minimize environmental damage from arch bridges, a structurally stable scheme that can resist variable external loads is required. This paper proposes a segmented precast arch bridge with outriggers to resist both the tensile force applied on the precast panels and the compressive force during construction and use. To assess the structural behavior and safety of the proposed arch bridge, a three-dimensional (3D) nonlinear structural analysis was conducted, considering the construction step and rise ratio of the arch bridge. The structural analysis of the proposed arch bridge revealed that its maximum horizontal and vertical displacements occurred at the support of the precast panel and the arch crown in a self-weight state. However, because of the compressive resistance characteristics of the outriggers connected to the precast panels, the structure demonstrated an effective performance in the self-weight state. With an increase in the construction steps, and the final completion of proposed arch bridge via installation of the precast arch segments and earthwork for the precast arch bridge with outriggers, the deformation of the arch members was mitigated, and the relative difference between the stress distributions of the members reduced. Hence, the arch bridge achieved structural stability. Based on the thrust line analysis results of the arch bridge with respect to the construction step using 3D structural analysis results, the thrust line was formed outside the precast panel at the arch crown and support, so was attributed to the behavior of the arch bridge in a self-weight state. The thrust line was found to act within the precast panel depending on the construction step. Analysis results confirmed that the behavior of the precast panel arch bridge with the proposed outrigger was stable and structurally effective.

Keywords

• precast panel
• outrigger
• arch bridge
• segmented precast
• underground arch
• nonlinear analysis