## 1 Introduction  
The aorta is the main artery in the human body, originating from the left ventricle of the heart and extending down to the abdomen, where it splits into two smaller arteries. It distributes oxygenated blood to all parts of the body through systemic circulation. However, aortic aneurysms--characterized by reduced stiffness of the arterial wall--may develop, which results in the expansion of the lumen due to several factors, such as smoking, alcohol consumption, hypertension, genetic influences, and atherosclerosis. Aneurysms have different names according to their position, and their geometry is also different depending on the location. In particular, an abdominal aortic aneurysm is a localized enlargement of the abdominal aorta with a diameter >3.0 cm or 50% larger than the normal diameter. These abdominal aortic aneurysms occur most commonly in individuals aged 50 years for men and 60 to 70 years for women, as well as those with family history [1]. Additional risk factors include smoking, high blood pressure, other heart or blood vessel diseases, and genetic conditions, including Marfan syndrome and Ehlers-Danlos syndrome, which increase risk [2]. According to the guidelines of the European Society for Vascular Surgery, it can be seen that important risk factors for abdominal aortic aneurysms are advanced age, male gender, and smoking. Smoking is a particularly strong risk factor, and smoking-related risks are much higher than for either coronary artery disease or stroke. In addition, it can be seen that the average growth rate of abdominal aortic aneurysms is from 30 mm to 55 mm, and the ranges are from 2 mm to 3 mm per year [2]. In these abdominal aortic aneurysms, ruptures are very lethal and the mortality rate is from 85% to 90%. In particular, the aneurysms are normally asymptomatic until a rupture. Hence, the aneurysms should be identified and treated before any ruptures occur, and surgery is usually recommended for abdominal aortic aneurysms with a diameter of \(>\)5.5 cm in men or \(>\)5.0 cm in women in order to prevent aortic ruptures [1]. However, there are some problems in the surgical judgement criteria for abdominal aortic aneurysms. In particular, many clinicians are having difficulty in examining the cause and making accurate judgements of aortic aneurysms, partly because aortic ruptures more commonly occur even if the diameter is \(<\)5.0 cm. Hence, studies on the risk factors of abdominal aortic aneurysms have been conducted in recent decades, and some studies reported the significant associations of these factors with the number of patients with abdominal aortic aneurysms. Nevertheless, studies that quantitatively analyze the location, propagation rate, and rupture risk of abdominal aortic aneurysms are rarely able to be found. Therefore, the mechanical analysis in identifying the precise material behavior and degradation of abdominal aortic properties according to the major factors should be performed in order to solve these problems. Experimental and computational analyses of the extracted tissues from carcasses, cadavers, and patients have been conducted to identify the precise material behaviors and properties based on various factors, such as vascular location [3; 4; 5; 6; 7], layer [8; 9; 10; 11], diameter [12], and smoking preference [5] in leading overseas research institutions for many decades [13; 14; 15; 16; 17]. In particular, [PERSON] et al. [3] have quantitatively studied the impact of tissue variations on the passive mechanical response of aneurysms in the supra-physiological loading range via mechanical testing and constitutive modeling. They conducted uniaxial extension tests on circumferentially and axially oriented strips from five thoracic and eight abdominal aortic fusiform aneurysms. As a result, they found the differences on the material behavior between the diseased thoracic and abdominal tissues and between healthy and diseased tissues.