Experimental study on construction vibration during different phases of diaphragm wall-supported deep excavation and its influence on indoor sensitive receivers

Construction vibration during deep excavation supported by diaphragm walls was experimentally investigated. First, measurement on the ground vibration induced by panel excavation for diaphragm wall installation was made inside a construction site. Results showed that the vibration level during excavation was much higher than ambient vibration at most frequencies, especially near the fundamental frequencies of the ground and the grab, and the strongest vibration was induced by the grab impacting the ground and guide walls. At another site, indoor ground-borne vibration was measured at two zebrafish laboratories at B1 and 3F of adjacent buildings during phases of existing pavement demolition, panel excavation, and basement excavation. The behavior of zebrafishes was observed simultaneously to examine the influence of vibration. Pavement demolition caused considerable increase in vibration level at B1 for nearly all frequencies, whereas at 3F the increment was more remarkable yet limited to a narrower bandwidth. Excavation of both panel and basement slightly enhanced the vibration magnitude at B1 at frequencies above 63 Hz or higher yet was hardly influential at 3F. Zebrafishes at B1 exhibited more startle response than those at 3F in all phases possibly because the construction vibration at B1 fell within the frequency range of vibration detection of zebrafishes. According to ISO 2631-1, this indoor vibration was perceptible to people only in some situations yet caused no discomfort.