Direct simulation of the tensioning process of cable-stayed bridge cantilever construction

The construction analysis of cable-stayed bridges plays a crucial role in the security of such structures because stresses and deflections attained during construction might exceed those in service. Although some commercial software are capable of simulating this, their main drawback is that they typically apply the stage superposition principle, owing to which the intermediate stages cannot be analyzed independently. Moreover, under this approach, the corrections of the tensioning process due to deviations in the cable stresses measured on site are more difficult. In this study, we conducted a direct simulation of the construction process of cable-stayed bridges built using the cantilever erection method by analyzing independent finite element models. To assure the achievement of a certain target state after construction (objective service stage, (OSS)), the prestressing forces in these models were modeled as imposed strains based on the unstressed length concept. Thus, the construction process can be simulated faster when time dependent phenomena are neglected. Moreover, this will lead to the direct simulation of the construction stages and OSS. To illustrate the application of the proposed method, a cable-stayed bridge was analyzed.