Quantitative evaluation method of human comfort under the influence of blast vibration based on human physiological indexes and its application

Abstract

To reasonably assess the impact of blasting disturbance on personnel in the adjacent area and to protect the safety and physical and mental health of personnel, it is the key to construct a human comfort evaluation system under the impact of blasting vibration. In view of the uncertainty of human subjective feelings in the existing evaluation system of human comfort under the influence of blasting vibration, the human vibration response experiment is carried out by simulating blasting vibration through a shaking table, and the quantitative relationship between blasting vibration parameters, ECG indicators, and human subjective feelings is analyzed by combining with human ECG indicators to construct the evaluation system of human comfort under the influence of blasting vibration. At the same time, the evaluation system is applied to the actual project with Wuhan Metro Line 5 as the engineering background by combining numerical calculation methods. The results show that: the vertical direction is the main vibration direction affecting human comfort, and the impact of vibration on the human body is related to the main vibration sensation parts of the human body, and the degree of impact gradually increases when the main vibration sensation parts moves up from the feet to the head; There is a quantitative relationship between the decreased ratio of human ECG index RMSSD and blasting vibration parameters as well as human subjective feelings, when the decrease ratio of human RMSSD is >0.28, the extent to which the human feels the degree of annoyance cannot be ignored, and the vibration velocity and frequency (0.7 cm/s, 80 Hz) in the vertical direction of the ground surface at this time can be used as the control threshold of blasting works in the adjacent densely populated areas. It is recommended that the maximum explosive charge in the single delay of the subway tunnel blasting excavation does not exceed 0.32 kg.