Dados do Trabalho

Título

The Effect of the Pile Cushion on the Data Quality in the Dynamic Load Test

Palavras-chave

Dynamic Load Test, Pile Driving Analyzer (PDA), Data Quality, Pile Cushion, Tension Stress.

Resumo (no máximo 200 palavras)

A good PDA Test outcome requires good dynamic data (Murakami, 2015). Moreover, sensors must be firmly attached to the pile to provide a good PDA test (Likins and Rausche, 2008). Some other effects may provide a bad outcome: an eccentric blow, the follower's failure, and the concrete's quality where the bolts were attached (Murakami et al., 2022). This paper presents a case study in which a different source caused poor-quality data. The Dynamic Test was performed in a 29.5cm-square precast concrete pile. For a low-energy blow (40cm drop height), the PDA showed a high tension stress of 3.0MPa, while in the other piles, this tension stress commonly occurred with higher energy (80cm drop height or more). In addition, the force and velocity signals qualitatively were different compared to the other piles. The sensors were firmly attached to the pile, and the pile-driving machine's hammer seemed well-adjusted to provide a non-eccentric blow. Then, after about 2cm of the pile cushion had been removed, the Dynamic Test has performed again, resulting in good-quality data. This case study shows the need for data quality in the Dynamic Load Test, and some unusual force and velocity signals must be investigated to provide good-quality data.

Palavras Chave

Data Quality; Dynamic Load Test; Pile Cushion; Pile Driving Analyzer (PDA); Tension Stress

Arquivos

Área

Ensaios de Carregamento Dinâmico, Teste Bidirecional: instrumentação e controle