The numerical investigation focused on the shear behavior of prestressed concrete (PC) beams with small rectangular openings, using the software ABAQUS. Three variables, including the prestressing force, the height of the opening and its length, were considered. The numerical results exhibited a good agreement with the previous experimental outcomes, and the parametric analysis was conducted to study the local internal force distribution of two chords during the loading process. The results indicate that for RC beams with openings, the shear proportion variation of the top chord is stable as the opening size changes, while it decreases almost linearly with the increase of prestressing force for PC beams with openings. The position of contraflexure point is found to be proportional to the root of the reinforcement ratio of the chord, and it moves towards the support with the increase of the prestressing force. Furthermore, the empirical equations to determine the shear proportions and the position of contraflexure point between chords are established.

中文翻译：

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矩形小开口预应力混凝土梁受剪性能的数值研究

数值研究的重点是使用ABAQUS软件对具有小矩形开口的预应力混凝土（PC）梁的抗剪性能。考虑了三个变量，包括预应力，开口的高度和长度。数值结果与以前的实验结果吻合得很好，并进行了参数分析，研究了在加载过程中两个弦的局部内力分布。结果表明，对于有开口的RC梁，随着开口尺寸的变化，顶弦的剪力比变化是稳定的，而随着有开口的PC梁的增大，其剪力比变化几乎呈线性减小。发现弯曲点的位置与弦的增强比的根成正比，随着预应力的增加，它趋向于支撑。此外，建立了确定剪切比例和弦之间反弯点位置的经验方程。