This study investigates the flexural performance and degree of composite action (DCA) of precast concrete sandwich panels (PCSPs) with four types of connectors. Five full-scale specimens were designed, and 4-point bending tests were performed. The specimens included four PCSPs utilizing glass fiber reinforced polymer (GFRP) truss connectors, steel truss connectors, concrete rib connectors, and GFRP pin connectors, respectively, along with a solid panel (SP). The results indicated that the flexural performance and DCA provided by the four types of connectors followed an ascending order as follows: GFRP pin-type connectors, GFRP truss connectors, steel truss connectors, and concrete rib-type connectors. Moreover, the study presented a novel method for calculating DCA, namely, the neutral axis method, which was compared with the displacement and strain methods. The reasonableness and accuracy of the neutral axis method in calculating DCA during the linear elastic stage were verified. Results indicated that the neutral axis method provided more precise and reasonable DCA that closely matched the experimental results compared with the displacement and strain methods. Additionally, the neutral axis method was simpler to calculate DCA and had a broader range of applications. Finally, the study provided recommendations for the optimal application scenarios of each calculation method.

中文翻译：

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预制混凝土夹芯板弯曲性能研究及新型复合作用度计算公式

本研究研究了具有四种连接器的预制混凝土夹芯板 (PCSP) 的弯曲性能和复合作用程度 (DCA)。设计了五个全尺寸试件，并进行了四点弯曲试验。样本包括四个分别使用玻璃纤维增​​强聚合物 (GFRP) 桁架连接器、钢桁架连接器、混凝土肋连接器和 GFRP 销连接器的 PCSP，以及一块实心板 (SP)。结果表明，四种连接器的弯曲性能和DCA按升序排列为：GFRP销式连接器、GFRP桁架连接器、钢桁架连接器和混凝土肋式连接器。此外，该研究提出了一种计算DCA的新方法，即中性轴法，并与位移和应变法进行了比较。验证了中性轴法计算线弹性阶段DCA的合理性和准确性。结果表明，与位移和应变方法相比，中性轴方法提供了更精确、更合理的 DCA，与实验结果更加吻合。此外，中性轴法计算DCA更简单，应用范围更广。最后，研究为每种计算方法的最佳应用场景提供了建议。