Experimental investigation of response of HSTC beam encased with Hf‐ECC and LWAC

The present investigation deals with the flexural behavior of a new type of Hybrid steel, polypropylene Engineered Cementitious Composite (Hf‐ECC) ‐ Lightweight Aggregate Concrete (LWAC) encased Hybrid Steel Truss Composite (HSTC) beams and detailed parametric study of HSTC beams using Abaqus. Eight simply supported beams fabricated with identical hybrid steel truss, but with varying depths and layer arrangement of Hf‐ECC and LWAC were experimentally tested to investigate the effects of Hf‐ECC depth of HSTC beam on the ultimate load‐carrying capacities and failure modes. Test results show that cracking, yield, ultimate moments, and the ductility of HSTC beams are improved by increasing the depth of Hf‐ECC due to the excellent tensile properties of Hf‐ECC. In addition to the above enhancement, it is also found that the combined use of Hf‐ ECC and LWAC could improve the beams' general ductility and considerable energy dissipation capacity due to Hf‐ECC's excellent deformation ability besides reducing beams' weight. In addition to experimental work, a finite element model is used to predict the load‐deflection behavior of Hf‐ECC and LWAC‐encased HSTC beams.