Flexible Behavior of Transverse Joints in Full-Scale Precast Concrete Slabs with Open-Type Joint Method

Abstract

Cracks and concentrated stresses can develop in precast concrete slabs, depending on the quality of the joints. The open-type joint method was adopted herein to fabricate a full-scale precast concrete slab joint. The open-type joint method features an exposed joint configuration that allows for direct installation of shear connectors without temporary formwork, improving constructability and load transfer efficiency. Full-scale load testing was carried out using a four-point loading experiment, revealing that the precast concrete slab had a yield load of 550 kN and maximum load of 733 kN. A slab using the cast-in-place method was measured to have a yield load of 500 kN and maximum load of 710 kN. A finite element analysis (FEA) model modeled the precast concrete slab, and the displacement and maximum load were analyzed. The FEA showed a maximum error within 7%. Therefore, the FEA results can predict the structural performance of the load–displacement of the precast concrete slab. The support vector regression model predicted key structural performance indicators such as concrete compressive strength, maximum load, displacement, and principal stress. The prediction results indicated that the average error converged within 3%. The prediction results of the SVR model can complement FEA by estimating outcomes without the need for complex modeling. Thus, the precast concrete slab using the open-type joint method was able to achieve structural performance equivalent to that of the slab using the cast-in-place technique. Furthermore, FEA and machine learning will be able to predict the structural performance of precast concrete slabs using the open-type joint method.