Flexural performance of assembly integral floor structure voided with steel mesh boxes

Abstract

Enhancing the ease of construction of fillers and large-span floors and their overall mechanical performance is critical for prefabricated hollow slabs in modular building structures. Therefore, we propose a novel assembly integral two-way hollow floor structure (8.4 × 8.4 m) consisting of permanent fillers (BDF ribbed steel mesh box) and three precast one-way hollow-core slabs with I-shaped flexural sections to address the above problem. This report evaluates the overarching flexural mechanism of a large-span full-scale model of the proposed system under uniform vertical loads. The experiment supports that the structure possesses a high bi-directional vertical bearing capacity and achieves the purpose of turning three one-way precast slabs into a two-way integral floor. The deflection value of the cast-in-site concrete frame beam, as the junction between the precast and cast-in-situ sections, is 88% below the damage limit value in GB/T 50152–2012. The strain of the bottom rebars in the ribbed girder of the precast hollow slab is identical to in the hidden girder. The strain profile in the mid-span of the frame beam reveals a noticeable membrane effect, strengthening the bending resistance of the system. Additionally, the original structure was modeled using ABAQUS to study the damage mechanism further. The analysis of the plastic development history and stress-strain distribution of the specimen reveals that upgrading the concrete strength has a slight improvement on the stiffness but could lessen its damage. While rationalizing the steel configuration is a more cost-effective option. Based on the pseudo-plate method and simulation results, the deflection and internal force equations were also recommended for preliminary design.