Ferretti Elena, Pascale Giovanni
Department of Civil, Environmental and Materials Engineering-DICAM, Alma Mater Studiorum Università di Bologna, 40136 Bologna, Italy.
Materials (Basel). 2019 Apr 10;12(7):1171. doi: 10.3390/ma12071171.
The purpose of this study is to improve the performance of walls under out-of-plane loads especially when subjected to the hammering action of the floors. The idea behind the paper is to provide the masonry walls with a device that behaves like a buttress, without having to build a traditional buttress. The solution presented in this paper consists of a mechanical coupling between the three-dimensional net of steel ribbons of the CAM (Active Confinement of Masonry) system and the CFRP (Carbon Fiber Reinforced Polymer) strips. Since the steel ribbons of the CAM system have a pre-tension, the mechanical coupling allows the steel ribbons to establish a semi-rigid transverse link between the CFRP strips bonded on the two opposite sides of a wall. Therefore, two vertical CFRP strips tied by the steel ribbons behave like the flanges of an I-beam and the flexural strength of the ideal I-beam counteracts the out-of-plane displacements of the wall. The experimental results showed that the combined technique inherits the strong points of both constituent techniques. In fact, the delamination load is comparable to that of the specimens reinforced with the CFRP strips and the overall behavior is as ductile as for the specimens reinforced with the CAM system. They also inspired a more performing combined technique.
本研究的目的是提高墙体在平面外荷载作用下的性能，特别是在承受楼板锤击作用时的性能。本文背后的理念是为砌体墙提供一种类似于扶壁的装置，而无需建造传统的扶壁。本文提出的解决方案包括CAM（砌体主动约束）系统的三维钢带网与CFRP（碳纤维增强聚合物）条带之间的机械耦合。由于CAM系统的钢带具有预张力，这种机械耦合使钢带能够在粘结在墙体两侧的CFRP条带之间建立半刚性横向连接。因此，由钢带系在一起的两条垂直CFRP条带的作用类似于工字梁的翼缘，理想工字梁的抗弯强度可抵消墙体的平面外位移。实验结果表明，这种组合技术继承了两种组成技术的优点。事实上，分层荷载与用CFRP条带加固的试件相当，整体性能与用CAM系统加固的试件一样具有延性。这些结果还启发了一种性能更优的组合技术。
