针对深基础工程在冲击波作用下的防护问题，本项目将设计双向梯度声子晶体(斗篷)，使冲击波的传播路径逐渐偏离深基础工程，减少冲击波能量向深基础工程的传递，起到遮挡冲击波的作用。主要研究内容包括：(1)根据设计频率范围内群速度方向的范围及传播路径的设计要求，确定梯度分布方式并建立双向梯度声子晶体(斗篷)的三维有限元模型，考察冲击载荷作用下深基础工程的时域/频域响应，揭示斗篷的隔冲击机理；(2)讨论材料、结构几何(包括水平/竖直梯度分布)等参数对深基础工程时域/频域特性的影响，拓宽隔冲击斗篷的工作频率范围，给出设计隔冲击斗篷的参考准则；(3)制作定向隔冲击斗篷模型，进行落锤或工程动载荷实验测试，实现斗篷遮蔽深基础工程的功能。本项目的研究将为隔冲击斗篷的设计奠定相关的理论与实验基础。

Regarding to the protection of deep foundation engineering under impact waves, the aim of the proposed project is to design bi-gradient phononic crystals (cloaking) for re-directing the impact waves far from the deep foundation engineering, reducing the energy transformation from impact waves to deep foundation engineering, realizing the impact-wave shading of deep foundation engineering. The main content includes: (1) according to the direction range of the group velocity in the considered frequency range and the design requirements of the propagation path, fixing the gradient form, designing and building the three-dimensional finite element models for bi-gradient phononic crystals (cloaking), investigating the effect of impact waves on the transient/harmonic responses of deep foundation engineering, exploring the mechanism of impact-wave shading; (2) discussing effects of material or structural parameters (including the horizontal/vertical gradient distribution) on the transient/harmonic responses of deep foundation engineering under impact waves, enlarging the working frequency range of cloaking, providing reference principle for the design of cloaking; (3) manufacturing directional cloaking model, carrying out drop hammer or dynamic loading tests, realizing the impact-wave shading of deep foundation engineering. The current research is expected to provide a theoretical and experimental basis to design cloaking for impact-wave shading.