Evaluating Sensitivity of an AAR-Affected Concrete Arch Dam to the Effects of Structural Joints and Solar Radiation

Abstract

Alkali aggregate reaction may affect the ultimate strength and structural performance of wet concrete structures such as arch dams. In addition to chemically-dependent factors, such as alkali aggregate reactivity, humidity, the mixture materials, etc., some other parameters intensify the complexity of the reaction simulation. In this regard, structural responses, i.e., stress values, cracks and their distributions, as well as thermal status of the damaged structures are known significant factors. The accuracy and quality of modeling for the aforementioned factors, may affect the validity of performed simulations. Contraction joints impress the structural reactions and solar radiation mainly impresses the dam thermal distribution. In the present paper, effects of both mentioned parameters during simulating the performance of a double-curvature concrete arch dam suffering from alkali aggregate reaction are evaluated. A computer program previously developed by the authors is utilized for modeling the selected case study. In addition to the final step results, the histories of structural responses during the dam life time are accounted for. The final results show high importance of both phenomena when stresses are evaluated but, the effect of solar radiation is ignorable when only crest displacements are considered. However, the deduction is somehow different when responses of a middle step are compared. Such differences would be more impressive to final results when nonlinear materials are assigned to the model and may be a shortcoming for the simulations in which the material behavior is assumed linear-elastic.

Simulating Structural Responses of a Generic AAR-Affected Arch Dam Considering Seismic Loading

“…It should be noted that a transient thermal analysis is performed before the structural analyses. Solar radiations were modelled in the aforementioned simulations using a precise formulation utilized by the authors during the previous studies [19,20]. Meanwhile, the variation of the reservoir surface level was elaborated based on the recorded history in the dam site.…”

A Review on Thermo-mechanical Modelling of Arch Dams During Construction and Operation: Effect of the Reference Temperature on the Stress Field

“…Regarding insolation, the exact trajectory of the sun throughout the year in the location of the dam can be computed and applied [18,56], as well as the shadows [89]. However, clouds generate local modifications that are complicated to include and can strongly modify the theoretical radiation.…”