Investigation of adaptive prestressing for concrete structures

目前设计和建造民用基础设施的做法是制造“被动”部件和系统。结构系统在初始建造时是固定的，除非采取有目的的干预，否则在结构的整个生命周期中保持不变。这个项目挑战了我们的结构在未来需要保持被动的概念。通过结合材料和传感技术的进步，将研究主动控制和改变结构系统以响应不断变化的载荷条件的概念。具体地说，将开发混凝土梁的自适应预应力技术。梁将由混凝土建造，但将有内部钢筋，可以根据施加在梁上的荷载将其受力到任何所需的拉力水平。利用生物类比，肌腱将类似于身体的肌肉；当没有负荷时，它将放松，但当有负荷时，它将收缩。收缩的大小将随所施加的负荷量而变化。这一概念的主动或自适应控制将彻底改变我们构思和创造未来结构系统的方式。

Current practice in the design and construction of civil infrastructure is to create 'passive' components and systems. The structural system is fixed at the time of initial construction and remains unchanged throughout the life of the structure unless purposeful intervention is taken. This project challenges the concept that our structures need to remain passive in the future. Through combining advances in materials and sensing technology, the concept of actively controlling and changing the structural system in response to changing loading conditions will be investigated. Specifically technology for adaptive prestressing of concrete beams will be developed. The beam will be constructed of concrete but will have an internal steel tendon which can be stressed to any desired level of tension in response to loads being applied to a beam. Using a biological analogy, the tendon will be similar to a muscle in the body; it will be relaxed when there is no load but will contract when load is present. The amount of contraction will change in response to the amount of load being applied. This concept active or adaptive control will revolutionize the way we conceive of and create future structural systems.