Formation of cracks represents one of the major causes of concrete deterioration, which can lead to durability and safety issues. In this work, a novel crack closure system is developed, using polyethylene terephthalate (PET) polymer fibres embedded in a mortar mix. The PET polymer has shape memory properties and shrinks upon thermal activation, if free to do so, or otherwise exerts shrinkage restraint forces. A single knot was manufactured at each end of the PET fibres to provide mechanical anchorage into the mortar matrix. Mortar samples with embedded knotted fibres were pre-cracked and subsequently placed in an oven to thermally activate the polymers and induce the shrinkage mechanism into the fibres. Crack closure was measured in the range 45–100%, depending on the geometry, dimension and distribution of the fibres, and the size of the initial crack.

裂缝的形成代表混凝土劣化的主要原因之一，这可能导致耐久性和安全性问题。在这项工作中，使用嵌入砂浆混合物中的聚对苯二甲酸乙二酯（PET）聚合物纤维开发了一种新型的裂缝封闭系统。PET聚合物具有形状记忆性能，并且在自由激活时会在热活化时收缩，否则会施加收缩抑制力。在PET纤维的每端制造一个结，以将机械锚定到砂浆基质中。将具有嵌入打结纤维的砂浆样品进行预裂解，然后将其置于烤箱中以热活化聚合物，并引起纤维收缩机制。裂纹闭合的测量范围为45-100％，具体取决于纤维的几何形状，尺寸和分布，