Anti-water-penetration techniques are important to raise the durability of cement-based materials (CBMs). Here the water penetration resistances of cement mortars with ethylene-vinyl acetate copolymer (EVA) and styrene butadiene rubber (SBR) were in-situ and non-destructively probed by micro-focus X-ray computed tomography (μ-XCT). Caesium Chloride (CsCl) was mixed in water to enhance the contrast gradients of μ-XCT images. SEM and EDS tests were provided to assess the mortar microstructure changes induced by water penetration. Results show that the CsCl enhancement helps trace the water penetration fronts, while exerting minor influences on the water penetration kinetics. The polymers can greatly raise the resistance against the water penetration into the cement mortars. The pore blocking induced by the formation of polymer films on the surfaces of cement grains and aggregates may account for the enhanced water-penetration resistance. The findings of this work provide a new method to track the water penetration in CBMs by μ-XCT and deepen the knowledge in the anti-water mechanisms of polymer-modified cement materials.

防渗水技术对于提高水泥基材料（CBM）的耐久性很重要。在这里，通过微焦点X射线计算机断层扫描（μ-XCT）对乙烯-乙酸乙烯酯共聚物（EVA）和丁苯橡胶（SBR）的水泥砂浆的耐水渗透性进行了原位和无损检测。将氯化铯（CsCl）混合在水中以增强μ-XCT图像的对比度梯度。提供了SEM和EDS测试来评估水渗透引起的砂浆微观结构变化。结果表明，CsCl增强有助于追踪水渗透前沿，同时对水渗透动力学产生较小影响。聚合物可以大大提高抵抗水渗透到水泥砂浆中的抵抗力。在水泥颗粒和集料表面上形成聚合物膜引起的孔堵塞可能是增强的抗水渗透性的原因。这项工作的发现为通过μ-XCT追踪煤层气中的水渗透提供了一种新方法，并加深了聚合物改性水泥材料的抗水机理知识。