Noise Reduction of Construction Equipment Vehicle Through Structure-borne and air-borne Noise Reduction Strategy

One can witness the constant development and redevelopment of cities throughout the world. Construction equipment vehicles (CEVs) are commonly used on the construction site. However, the noise pollution from construction sites due to the use of CEV has become a major problem for many cities. The construction equipment employed is one of the main causes of these elevated noise levels. The construction workers face a potential risk to their auditory health and well-being due to the noise levels they are exposed to. Different countries have imposed exterior and operator’s ear noise limits for construction equipment vehicles, enabling them to control noise pollution. In this study, three vehicles were selected and checked for NVH performance and found that the operator ear noise level of the identified vehicle is 6 dB(A) higher than the benchmark vehicle level in dynamic conditions, when tested as per ISO 6396. Similarly, there was another vehicle having exterior noise 2 dB(A) higher than the benchmark vehicle, when tested as per ISO 6395. It was a tough time for the NVH engineer to reduce the interior and exterior noise level of the vehicle. The steering unit and radiator fan were identified as the major dominant sources rather than typical conventional sources like powertrain, intake, and exhaust. Initially, the noise source identification technique was used to identify the dominant sources for increasing the interior and exterior noise of the test vehicle. The primary concern identified with the vehicles was the transmission of structure-borne noise into the cabin and air-borne noise to the exterior. It was foremost required to address the issues without compromising the overall performance of the vehicle other than NVH. Individual sources of noise were analyzed in detail and optimizations were made to minimize the vehicle interior and exterior noise. As a result, the significant noise reduction was achieved at operator ear level and exterior sound power level.