损伤容限（damage tolerance）是一种较新的结构设计理论。该理论假设，任何结构材料内部都有来自加工及使用过程的缺陷，而设计者的任务是利用各种损伤理论（如断裂力学）以及给定的外载荷，确定这些缺陷的扩展速度以及结构的剩余强度。

对于经受变化载荷的结构，如飞机、轮船、车辆等，损伤容限设计要结合无损探伤技术和疲劳理论，提供结构的检验期限，以保证结构中存在的裂纹在该期限内不会扩展为临界裂纹。

Damage tolerance is a property of a structure relating to its ability to sustain defects safely until repair can be effected. The approach to engineering design to account for damage tolerance is based on the assumption that flaws can exist in any structure and such flaws propagate with usage. This approach is commonly used in aerospace engineering to manage the extension of cracks in structure through the application of the principles of fracture mechanics. In aerospace engineering, structure is considered to be damage tolerant if a maintenance program has been implemented that will result in the detection and repair of accidental damage, corrosion and fatigue cracking before such damage reduces the residual strength of the structure below an acceptable limit.