Author(s): Keigo Namikawa; Naoki Koyama; Taro Kusagaya; Keiichi Suzuki; Tomohito Yamada; Tadashi Yamada

Linked Author(s): Tadashi Yamada

Keywords: Cosmic ray muon; Tomography analysis; Moore Penrose inverse; Singular value analysis; Tikhonov regularization

Abstract: River embankments have been constructed and reconstructed to resist extensive damage due to failure. However, the soil materials and compaction methods used have varied over time, which can cause localized voids and land subsidence that can lead to failure. Therefore, it is very important to know the presence and location of low-density and weak areas internal embankments. There are few ways to detect them. For example, Geophysical exploration has been used to estimate inside of ground, but conventional methods do not provide information on ground based on its physical properties and require specialist skills and knowledge to estimate extent of weak points and to interpret the results. In this study, the aim is to study the effectiveness of exploration technology using cosmic ray muon for understanding the internal structure of embankments, which can directly determine the ground density and are suitable for the scale of embankment exploration (spatial resolution 0.1- 1.0 m, exploration depth 1.0-10 m). To verify the validity of exploration using muon, the number of muons through the embankment is observed. To visualize the internal density distribution internal of the embankment, a tomography analysis was carried out in a way that the analytical values were independent of the initial values. The results of the analysis show that the analyzed density values internal the embankment generally agree with the actual embankment ground density data. Furthermore, the high-density areas representing the concrete were clearly visible.

DOI: https://doi.org/10.3850/978-90-833476-1-5_iahr40wc-p1459-cd

Year: 2023