Summary: | 碩士 === 國立高雄應用科技大學 === 土木工程與防災科技研究所 === 94 === Standard Penetration Test(SPT) has been extensively used in civil engineering. Due to wrong operation performed and inexact equipment, the judgment of formation of soil layers lead to error or imperfections by using SPT N-value. Therefore, it generally needs to many different ways to modify so that N value can be used in geotechnical applications. The purpose of this study is to estimate the energy loss using energy measurement system for SPT and for providing SPT N- value correction for reference. The research methods are focused on design and setup the load cell and the accelerometer on the energy measurement rod. In addition, the industrial panel computer (IPC) and high-speed analogy-to-digital converter (ADC) card are used to acquisite and record the test data. Moreover, the Mass-Spring-Slider (MSS) model is proposed to estimate the relationship among the displacement, velocity, and acceleration of drill rod. The result showed that the joint of drill rod influenced the shape of first pressure wave and measurement energy of manual hammer was little higher than that of automatic hammer. In other words, the N-value will be underestimated. Besides, the MSS model should be needed to limit the deformation by Slider element otherwise the displacement of model should continue to increase with force. In addition, the maximum energy occurred most frequently on, or near, the first pressure wave in load cell response.
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