This paper proposed a distributed seismic damage sensing network using PZT-based smart aggregates for RC building structures, aiming to monitor the structural local seismic response. The stress history and the crack patterns of the structure under earthquake load in positions of interest are the two key issues to be monitored. The concept of the seismic damage mechanism monitoring by means of direct piezoelectric effect and stress wave propagation evaluation is proposed. The proposed smart aggregates consist of PZT sensing element and the stone holding matrix. Its senssitivity for dynamic compressive stress induced by earthquake load and the influence of pre-stress from dead load of building structures after embedment are discussed. It is shown that the proposed smart aggregates suits for seismic stress monitoring and the static pre-stress has no significant influence on its performance.© (2011) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.