The current report is devoted to the flexural analysis of a composite structural insulated panel (CSIP) with magnesium oxide board facings and expanded polystyrene (EPS) core, that was recently introduced to the building industry. An advanced nonlinear FE model was created in the ABAQUS environment, able to simulate the CSIP’s flexural behavior in great detail. An original custom code procedure was developed, which allowed to include material bimodularity to significantly improve the accuracy of computational results and failure mode predictions. Material model parameters describing the nonlinear range were identified in a joint analysis of laboratory tests and their numerical simulations performed on CSIP beams of three different lengths subjected to three- and four-point bending. The model was validated by confronting computational results with experimental results for natural scale panels; a good correlation between the two results proved that the proposed model could effectively support the CSIP design process.

中文翻译：

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氧化镁板饰面的复合结构隔热板的抗弯性能

本报告专门研究具有氧化镁板饰面和膨胀聚苯乙烯（EPS）芯的复合结构绝热板（CSIP）的弯曲分析，该结构最近被引入建筑行业。在ABAQUS环境中创建了先进的非线性有限元模型，能够详细模拟CSIP的弯曲行为。开发了原始的自定义代码过程，该过程允许包括材料双模量以显着提高计算结果和故障模式预测的准确性。在实验室测试的联合分析中确定了描述非线性范围的材料模型参数，并对在三种不同长度的三点和四点弯曲的CSIP梁上进行了数值模拟。通过将计算结果与自然比例面板的实验结果相面对来验证该模型；两种结果之间的良好相关性证明，该模型可以有效地支持CSIP设计过程。