The numerous advantages of solid slabs, including adequate rigidity, appropriate fire resistance, and sound insulation, have further extended the system’s applications. The main disadvantage of this system is, however, its extreme weight, especially in long spans. Since concrete is not involved in bearing in the tensile zone, its removal can lower the weight without affecting the load bearing of the slab. In a number of systems, named biaxial voided slabs, ellipsoidal or spherical sacrificial plastic balls are used to create voids within the concrete. As this system has just been introduced, considerable uncertainties have been raised about one-way and two-way shear behaviors of the system. Accordingly, four full-scale specimens were built in order to investigate these behaviors. Two one-way and two two-way full-scale shear specimens with dimensions of 3500 × 1200 × 200 mm and 2300 × 2300 × 200 mm (length × width × height) were constructed, respectively. These specimens were used to compare the shear capacity, cracking distribution, and deflection in solid and biaxial voided specimens. Also, the effect of vertical rods of steel cages on the shear behavior was investigated. The results show the steel cages clearly contributed to shear bearing; and although the shear capacity of voided specimens was less than solid ones, the failure mode of all specimens was shear. Finally, a new method was proposed to predict the ratio of shear capacity of biaxial voided slabs to solid slabs. Hence, the proposed method can predict the ratio of biaxial voided capacity to solid slab capacity with an adequate precision.

实心平板的众多优点，包括足够的刚性，合适的耐火性和隔音性，进一步扩展了系统的应用范围。然而，该系统的主要缺点是其极重，特别是在大跨度时。由于在拉伸区域的轴承中不涉及混凝土，因此去除混凝土可以减轻重量，而不会影响平板的承重。在许多称为双轴空心板的系统中，使用椭圆形或球形的牺牲塑料球在混凝土内部产生空隙。随着刚刚引入该系统，已经对该系统的单向和双向剪切行为提出了相当大的不确定性。因此，为了研究这些行为，建立了四个完整的标本。分别构建了两个单向和两个双向全尺寸剪切标本，尺寸分别为3500×1200×200 mm和2300×2300×200 mm（长×宽×高）。这些标本用于比较固体和双轴孔隙标本的剪切能力，裂缝分布和挠度。此外，研究了钢笼垂直杆对剪切行为的影响。结果表明，钢保持架明显有助于剪切承载。尽管空洞试样的剪切能力小于实心试样，但所有试样的破坏模式均为剪切。最后，提出了一种新的方法来预测双轴空心板与实心板的抗剪承载力比。因此，所提出的方法可以以足够的精度预测双轴空隙率与实心板坯率的比率。