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SEFE11
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The pile (P45) was driven by a vibratory hammer (EK-180) up to 15.5 m depth. The Standard Penetration Test (SPT) indicated a 1.5m landfill, followed by soft clay up to 13.3 m. Underneath this layer, sandy silt soil was observed. The Dynamic Load Test (DLT) was performed through the Dynamic Increasing Energy Test (DIET) proposed by Aoki (1989, 1997). Moreover, the signal-matching analysis was done according to the new procedure for the CAPWAP analysis in the DIET (Murakami, 2015, 2019). The initial studies observed that this procedure had shown positive correlations for precast concrete piles (Murakami, 2015). However, Murakami and Massad (2023) observed that this procedure applies to other pile types. Murakami (2019) proposed using the littlest achievable shaft quake to access the best traditional Match quality calculated on the Wave Up Curve (MQWU). In this case, the CAPWAP matches the slope of the pile-top load of the Static Load Test versus the settlement curve at early loads. In this context, the concept of match quality of settlements (MQS) arises. Traditionally, the correlation between SLT and DLT is done by the Davisson Offset or the NBR 6122 Methods. The last one is used in Brazil and may indicate a slightly higher load compared to the Davisson Method. This paper aims to present a comparison between SLT and DLT in steel piles (W360x32.9) through different methods: 1) Match Quality of Settlements (MQS); 2) Davisson Offset; 3) NBR 6122; 4) axial force in depth; The SLT was carried out 44 days after the end of the initial drive (EOID), while the dynamic test was done 62 days after the EOID. Both tests were done in the same pile (P45). The SLT reached a maximum load of 60.7 tons and a settlement of 45.3 mm, while the CAPWAP showed a maximum load of 55.0 tons and a settlement of 28.3 mm. A comparison through traditional methods shows that the Davisson Method reached a load of 48.6 tons for the SLT and 53.5 tons for the CAPWAP, a difference of 7.0 %. On the other hand, the NBR Method indicates 49.7 tons for the SLT and 53.5 tons for the CAPWAP, a difference of 7.6 %. Moreover, a good match was observed in the early loads between the tests. In this case, the alpha value of the MQS was 0.81, with an R2 of 0.9773. In addition, the instrumented SLT indicated a good agreement with the CAPWAP regarding the axial force in depth. The final paper will present: 1) axial force in depth in the SLT for each load increment and 2) axial force in-depth for CAPWAP analyses in each blow in the DIET. The conclusion is that the procedure proposed by Murakami (2015, 2019) improved the MQWU, and the output of the CAPWAP presented a good agreement with the instrumented SLT: 1) MQS close to the unit; 2) good correlation with traditional methods (Davisson and NBR 6122); 3) good correlation with the axial force in the depth of the SLT.
Evento criado e realizado, desde 1985, pela
Patrocínio Platina
Patrocínio Ouro
Patrocínio Prata
Patrocínio Bronze
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Apoio Técnico e Institucional
Apoio Institucional
Apoio de Divulgação