Producing high-ductility cementitious composites (HDCC) increased in parallel with concrete demand in China recently. However, the high cost of manufacturing cementitious composites (HDCC) persists. To reduce the cost of HDCC, steel fibers, polyvinyl alcohol (PVA), and river sand were used to produce HDCC concrete in the present study. A total fiber content of 2% was formed with five different proportions of PVA fiber and steel fiber. Within the scope of the experimental studies, mechanical (workability, compressive strength, tensile, and bending properties), and microstructural (scanning electron microscopy) tests were carried out to investigate the properties of the hybrid fiber-reinforced composites. The results showed that the fluidity of HDCC increased with increasing steel fiber substitution. The compressive strength of the mixture containing 0.5% steel fiber and 1.5% PVA fiber exhibited a better compressive strength of 31.3 MPa. The tensile performance of the mixture was improved due to the incorporation of steel fiber. The initial cracking strength was about 2.32 MPa, 25.4% higher than that of the reference group, and the ultimate tensile strength was 3.36–3.56 MPa. However, reducing the content of PVA fiber impacts the flexural rigidity of the matrix.

Ceramsite concrete, with its advantages such as excellent long-term durability and thermal insulation properties, is suitable to be utilized as precast sandwich wall panels. While the lack of assessment of the seismic performance of such wall panel joints has been studied. Therefore, an experimental program was carried out to investigate and improve the seismic performance of the new type of wall panel joints. The seismic performances of the specimens were experimentally evaluated, including failure mode, loading and deformation capacity, ductility, the strain of vertically distributed steels, stiffness, and energy dissipation. The insulated sandwich wall panel joints have good seismic performance shown by the quasi-static test. The ductility coefficient of all specimens was greater than 3. The structure of the control group specimen presented a better match in stiffness, bearing capacity, ductility, and energy dissipation. The sleeve connection confirmed that the integrity of the joint, and the L-shaped hidden column could improve the ductility coefficient and equivalent viscous damping coefficient by about 4.2%. The results can promote the research of such wallboard system. This design approach of sandwich wall panel joints with lightweight concrete is broadly applicable to the exploration of more types of energy-saving wallboard systems.