This paper aims to study the use of Lebanese raw kaolin in the formulation of geopolymers (GP) mortars based on an experimental and numerical approach. Two classes of GP mortars were prepared: the first contained sodium (Na)-based alkali activator, while the second was prepared by adding potassium (K)-based activators. A microstructural characterization was realized before and after the calcination of the raw material. Mechanical characterization of the mortars was conducted by highlighting the impact of the two alkaline solutions used, on tests performed on days 1, 3, 7, 28, 90, and 120. Simultaneously, a three-phased heterogeneous numerical modeling (matrix, aggregates, pores) was used to obtain specific characteristics not accessible experimentally. As main results, the experimental work showed that the binding solutions’ nature and samples’ aging affected the microstructure and, consequently, the mechanical properties. K-based geopolymer mortar presents higher values of mechanical strength than Na-based geopolymer mortar. Moreover, an asymptotic behavior is observed in mechanical characteristics at about 90 days. The numerical results confirmed that micro-defects and porous network have an important impact on Young’s modulus values as well as the presence of the sand phase. The mechanical characteristics of pure binder samples were also obtained numerically. These samples contain natural defects and pores leading it impossible to obtain experimentally the desired characteristics. This work and the associated results confirm that Lebanese raw material can be considered as a sustainable construction material solution for Middle Eastern countries.

本文旨在通过实验和数值方法研究黎巴嫩生高岭土在地聚合物（GP）砂浆配方中的用途。制备了两类GP砂浆：第一类包含基于钠（Na）的碱活化剂，第二类通过添加基于钾（K）的活化剂制备。在原料煅烧之前和之后都实现了微观结构表征。通过突出使用的两种碱性溶液对第1、3、7、28、90和120天进行的测试的影响，对砂浆进行了机械表征。同时，进行了三相异质数值建模（基体，骨料，孔）用于获得实验无法获得的特定特征。作为主要结果，实验工作表明，结合溶液的性质和样品的老化会影响其微观结构，进而影响其机械性能。K基地质聚合物砂浆比Na基地质聚合物砂浆具有更高的机械强度。此外，在约90天时观察到机械特性的渐近行为。数值结果证实，微缺陷和多孔网络对杨氏模量值以及砂相的存在具有重要影响。还可以通过数值获得纯粘合剂样品的机械特性。这些样品含有自然缺陷和孔隙，导致无法通过实验获得所需的特性。