Multiscale experimental and numerical study of the thermomechanical behavior of composite sandwich panels towards the integration of environmental effects to the virtual testing method

复合材料夹层板在空间结构、海军结构、风力涡轮机、飞机等领域的应用越来越广泛。在这些应用中，由于复合材料结构的各向异性和非均匀性，夹层板会受到循环环境条件的作用，从而产生不同尺度的内应力。这些内应力的循环性质又会导致损伤的发展。温度和湿度也影响夹层板组分的力学性能和断裂行为。 开发复合材料结构需要大量的时间和金钱投资。正因为如此，行业正在转向数值模拟和虚拟测试。虚拟测试背后的原理是，复合材料结构开发所需的每个实验测试，从试样规模开始并向大规模测试发展，都可以使用数值模拟虚拟地进行。在各种实验条件下的测试是复合材料结构开发的一部分，因此可以集成到虚拟测试方法中。 拟议的研究计划的长期目标是将环境条件对复合材料结构力学行为的影响整合到虚拟测试过程中。为了做到这一点，需要更好地了解温度对复合材料结构及其成分的影响，并开发数值工具。目前，该研究计划的重点是温度的影响，但将来将包括湿度等其他环境条件的影响。作为一个起点，该项目是围绕复合材料夹层板作为主要类型的结构研究。然而，由于该研究计划旨在研究温度变化引起的现象的多尺度性质，层压板，核心和复合材料组件也是拟议研究计划的一部分。 该研究项目以A

Composite sandwich panels are increasingly used in many applications such as space structures, naval structures, wind turbines, aircraft, etc. In all of these applications, they are subjected to cyclic environmental conditions which leads to the development of internal stresses at different scales caused by the anisotropy and heterogeneity of composite structures. The cyclic nature of these internal stresses can in turn lead to damage development. Temperature and humidity also influence the mechanical properties and the fracture behavior of sandwich panels constituents. Large time and money investments are required to develop composite structures. Because of that, industries are turning to numerical simulations and virtual testing. The principle behind virtual testing is that each experimental test required for the development of a composite structure, starting at the coupon scale and evolving toward large scale testing, can all be performed virtually using numerical simulations. Testing in various experimental conditions is part of the development of composite structures and thus could be integrated to the virtual testing method. The long-term goal of the proposed research program is to integrate the effects of environmental conditions on the mechanical behavior of composite structures to the virtual testing process. In order to do so, a better understanding of the effect of temperature on composite structures and their constituents and the development of numerical tools are required. For now, the research program is focused on the effect of temperature, but will, in the future, include the effect of other environmental conditions such as humidity. As a starting point, the project is developed around composite sandwich panels as the main type of structures studied. However, because the research program aims to look at the multiscale nature of the phenomena caused by temperature changes, laminates, cores and composite assemblies are also part of the proposed research program. The research program is centered a