利用双参数地基模型修正反应位移法弹簧

Modified the spring of response displacement method using two-parameter foundation model

摘要:

为得到一种模型简单、计算精度高,且能更好反映土-结构相互作用的地下结构抗震设计方法,根据双参数地基模型的原理,用比传统单参数模型更加接近土体性质的双参数模型简化土体,并根据受力和变形特性对双参数计算模型进行简化,最终得到能考虑土体间相互作用的修正反应位移法.修正方法计算模型与传统反应位移法相比,仅仅是法向弹簧的基床系数进行了一定的修正,仍然是一种模型简单的计算方法.建立数值模型进行分析,以动力时程计算结果为基准,并与传统反应位移法作对比验证修正方法的正确性.结果表明,相比传统采用离散弹簧模拟土体的反应位移法,修正方法的内力及变形误差能减小一半左右,由此得到修正方法是一种模型简单且计算精度较高的设计方法,能够应用到地下结构抗震设计中.

Abstract:

To obtain a seismic design method for underground structures, which has simple model with higher accuracy and can better reflect the soil-structure interaction, this paper presents a modified response displacement method. The two-parameter foundation model was adopted to simplify the soil, which is closer to the soil properties than the traditional single-parameter foundation model. Based on the force and deformation properties, the two-parameter computational model was simplified, and the modified response displacement method was obtained, which considers soil-structure interaction. Compared with the traditional model, the proposed model only modifies the foundation bed coefficient of normal spring, making it still a simple computational model. In addition, a numerical model was established to verify the correctness of the modified method and compared with the traditional response displacement method based on the results of dynamic time-history calculation. Results show that the error of the modified method could be reduced by half compared with the traditional response displacement method. Therefore, the proposed method has simple model and high computational accuracy, which can be applied in the seismic design of underground structures.