Topological phononic crystals in the mechanical setup became a topic of great interest owing to their applicability in various engineering systems such as waveguides or vibration isolation devices. If such systems are composed of elastic structures, they are usually characterized by a bulk-edge correspondence where the geometrical and material properties can play important role in the existence of stable surface and boundary modes. This work investigates the band transition and topological interface modes in a beam array system, where two sub-lattices of vertically aligned, parallel, and elastically coupled beams are connected at the chain center. To illustrate the existence of interface modes and understand their behavior, the corresponding eigenvalue problem is solved and frequency response function is sought for the system with a finite number of unit cells. Localization of the interface modes is demonstrated based on the steady-state responses of the beam array system to harmonic excitation. The effects of introduced defect masses and inerters on interface states are studied separately. It is revealed that the introduction of a small defect mass in the form of concentrated mass attached to some beam in the system does not affect the interface modes within the observed frequency range. On the other side, inerters produce frequency shifts towards lower values, which even in the case of small values of the inerter parameter causes the interface modes to vanish or even to appear inside another frequency band gap. The obtained results give an insight into the influence of inerter devices and their mass amplification effect on the interface states in complex periodic elastic systems. It also investigates the possibility to tune interface modes without significantly affecting the main band structure properties of the system.

机械装置中的拓扑声子晶体因其在各种工程系统（如波导或隔振装置）中的适用性而成为人们非常感兴趣的话题。如果这样的系统由弹性结构组成，它们通常以体边缘对应为特征，其中几何和材料特性可以在稳定表面和边界模式的存在中发挥重要作用。这项工作研究了梁阵列系统中的能带过渡和拓扑界面模式，其中两个垂直对齐、平行和弹性耦合梁的子晶格在链中心连接。为了说明接口模式的存在并理解它们的行为，相应的特征值问题得到解决，并为具有有限数量单元的系统寻求频率响应函数。基于光束阵列系统对谐波激发的稳态响应，证明了界面模式的定位。分别研究引入的缺陷质量和惰性物质对界面态的影响。结果表明，以集中质量的形式引入系统中某些光束的小缺陷质量不会影响观察到的频率范围内的界面模式。另一方面，惰性物产生向较低值的频移，即使在惰性物参数值较小的情况下，这也会导致界面模式消失或什至出现在另一个频带间隙内。所获得的结果深入了解了惰性装置及其质量放大效应对复杂周期弹性系统中界面态的影响。它还研究了在不显着影响系统主要能带结构特性的情况下调整界面模式的可能性。