Dębska Aleksandra, Gwoździewicz Piotr, Seruga Andrzej, Balandraud Xavier, Destrebecq Jean-François
Aldebud Aleksandra Dębska, ul. Zyndrama z Maszkowic 11, 30-689 Kraków, Poland.
Faculty of Civil Engineeering, Cracow University of Technology, ul. Warszawska 24, 31-155 Krakow, Poland.
Materials (Basel). 2022 Jan 21;15(3):826. doi: 10.3390/ma15030826.
This paper deals with the mechanical behavior of hollow concrete cylinders prestressed with nickel-titanium (Ni-Ti)-shape memory alloy (SMA) wires wound around them. Prestresses can be created by the thermal activation of the memory effect of SMA wire placed on the outer surface of concrete cylinders. In order to assess the stress level in concrete, a model was used to analyze the thermal stresses in the concrete shell resulting from a temperature gradient in the thickness. Another model was used to calculate the circular concentric loading applied by the wound wire resulting from the impairment of its memory effect by the concrete cylinder. Finally, longitudinal compression tests were performed on the prestressed hollow cylinders. Longitudinal and circumferential strains were measured using gauges located on the surfaces of the hollow cylinders. The tests were performed almost one year after the application of prestressing by means of Ni-Ti SMA wire, confirming that the residual stress in the wire remained present. It may therefore be concluded that the prestressing of concrete elements designed with the use of Ni-Ti SMA material is effective for a long time.
本文研究了缠绕有镍钛（Ni-Ti）形状记忆合金（SMA）丝的空心混凝土圆柱体的力学性能。通过对置于混凝土圆柱体外表面的SMA丝的记忆效应进行热激活，可以产生预应力。为了评估混凝土中的应力水平，使用一个模型来分析由厚度方向的温度梯度引起的混凝土壳中的热应力。另一个模型用于计算由于混凝土圆柱体对缠绕丝记忆效应的损害而由缠绕丝施加的圆形同心荷载。最后，对预应力空心圆柱体进行了纵向压缩试验。使用位于空心圆柱体表面的应变片测量纵向和周向应变。试验在通过Ni-Ti SMA丝施加预应力近一年后进行，证实了丝中的残余应力仍然存在。因此可以得出结论，使用Ni-Ti SMA材料设计的混凝土构件的预应力在很长时间内都是有效的。
