A Study on the Influence of Bolt Arrangement Parameters on the Bending Behavior of Timber–Steel Composite (TSC) Beams

The present paper investigates the impact of bolt distance, diameter, and number rows on bending performance timber–steel composite (TSC) beams. This study aims to facilitate application connections in assembled TSC structures. Composite steel I-beams were designed with timber boards connected upper section bolts. Three-point static tests conducted nine beams divided into four groups (L1, L2, L3, L4) varying arrangements. destruction mode, ultimate bearing capacity, ductility coefficient, load–midspan deflection curve, strain curve each specimen obtained. In addition, mechanism, quantitative relationship between area ratio interfacial slip, ideal identified. It was found that when midspan beam approached prescribed limit, main failure mode can be explained as follows: top surface all specimens had longitudinal local splitting, except L1, which fewer bolts no obvious damage. Moreover, due compression because stress at lower edge I-beam entered flow amplitude stage, some crushed but not pulled off. high flexural load capacity maximum relative slips interfaces range 2–6 mm. also slip interface coefficient decreased steadily increased, while specimen’s increased. optimal determined 8 × 10−3. Using total area, we arrangement board. For convenience, multiple variables converted one variable. distance a greater diameter smaller impact. theoretical values good agreement experimental results, based superposition equations distances. effective formula segment provide instructions for control intersections engineering practices.