Because of geometric nonlinearities, vibrations in two horizontal directions can generate a torsional moment that induces a torsional response, even in a structure with no eccentricity; we term this phenomenon Q–Δ effect. In this study, the torsional response caused by the Q–Δ resonance was investigated by performing a shaking table test that involves a single‐layer symmetric specimen. The specimen was designed and fabricated by focusing on one of two resonance conditions. Its moment of inertia was adjustable by changing locations of weights, and the natural frequency in the torsional mode could be modified. We developed a numerical model of the specimen, in which the columns connected to the slab were integrated into an elastic Euler beam. It was confirmed that the torsional response increased near the predicted Q–Δ resonance point. In addition, the acceleration at the corner of the slab was significantly increased. The formulated equations of motion provided a better prediction of the actual phenomena. Because the specimen corresponds to a stiff and slender high‐rise building when converted into a full scale, the result suggests a need to be aware of the risk of torsional response increase due to the Q–Δ resonance.

中文翻译：

---

Q-δ共振引起的扭转响应实验

由于几何非线性，即使在没有偏心的结构中，在两个水平方向上的振动也会产生扭转力矩，从而引起扭转响应。我们称这种现象为Q–Δ效应。在本研究中，由Q–Δ引起的扭转响应通过进行涉及单层对称试样的振动台试验研究了共振。通过关注两个共振条件之一来设计和制造样品。它的惯性矩可以通过改变配重的位置进行调节，并且可以修改扭转模式下的固有频率。我们开发了样品的数值模型，其中将与平板相连的柱整合到弹性的Euler梁中。可以确定，扭转响应在预计的Q–Δ附近增加共振点。此外，平板拐角处的加速度显着增加。制定的运动方程式可以更好地预测实际现象。由于将标本转换为完整比例后，该标本对应于一个刚性且细长的高层建筑，因此结果表明需要意识到由于Q-Δ共振而导致扭转响应增加的风险。