TECHNICAL NOTE Innovative method for remote measurement of pile set and temporary compression of driven H-piles in Hong Kong

摘要

The final set and temporary compression (also known as the elastic rebound) of pile and soil of a driven H-pile are conventionally measured manually by a worker standing next to a pile during pile driving. While this manual method is currently used in Hong Kong and many other countries, it may pose a potential hazard in occupational safety and health and its accuracy may be affected by ground vibrations and human limitations. The Pile Driving Monitor (PDM) is an innovative and non-contact mobile device that provides a better alternative method. It allows measurements to be taken remotely and accurately at a safe distance of 5-25 m from a pile. The Hong Kong Housing Authority (HKHA) [The specification library 2008 edition (SL). Housing Department, Government of the Hong Kong SAR; 2008] instituted a pilot study in a housing project on the use of PDM. A total of 120 sets of parallel measurements by manual and PDM methods were obtained and the results were found in good agreement. PDM advantages in occupational safety and health, measuring accuracy, reliability and efficiency were well demonstrated. The use of PDM method has been accepted by the Hong Kong Buildings Department on project basis.