To effectively monitor the formation and development of cracks, a quantitative sensing method of static cracks using piezoelectric smart aggregates was proposed. The piezoelectric smart aggregate transducers were designed and the sensitivity of the sensing signals was tested and analyzed. The sensor shape, packaging material, input voltage and excitation frequency of smart aggregate were optimized. Quantitative sensing tests of crack location and depth were carried out, a relative energy index based on wavelet packet analysis was constructed, and the regular relationship among the energy indices and fracture location, depth was proved. Finally, a random aggregate FEM model was constructed to perform numerical simulation on the effect of cracks on the sensing signal. The results show that the numerical simulation results and the test results are well fitted, indicating that the use of piezoelectric intelligent aggregate can well monitor the crack damage of concrete structures. This method provides a new way for continuous, remote, and real-time monitoring of fracture occurrence and development.