In order to study the seismic wave attenuation characteristics of complex plate tectonics in and around the Kanto Basin, based on the focal mechanism and Slab1.0 model, the research area is divided into four regions. The one-step non-parametric generalized inversion technique was used to analyze the seismic wave attenuation characteristics of each region separately. The results show that the seismic path attenuation of earthquakes occurring in the shallow crust (Reg.1) is weak, and the seismic wave refraction at the crust–mantle boundary leads to almost no attenuation over a long hypocentral distance (>60 km), the frequency–dependent inelastic attenuation is also weak with the 0.5–20 Hz quality factor Q = 92.33f1.87. The seismic path attenuation of the upper mantle earthquakes occurring in the Kanto Basin (Reg.2) is strong, and the attenuation curve decreases with the increase of hypocentral distance, which is approximately parallel to the geometric diffusion R−2.0, the frequency–dependent inelastic attenuation is stronger with the quality factor Q = 27.75f1.08. The seismic path attenuation of subduction zone earthquakes (Reg.3 and Reg.4) is more obvious in the high–frequency band and has a frequency correlation, indicating that the attenuation of subduction zone earthquakes includes more inelastic attenuation. The frequency–dependent inelastic attenuation Q of Reg.3 and Reg.4 are 52.58f0.95 and 58.07f0.89, respectively.
The application of reinforcement with headed bars is widely used in the construction industry. Moreover, when the net distance between headed bars is close, the concrete areas for distributing bearing under the headed bars will overlap with each other. The local bearing capacity of concrete will also be affected by the overlapping area. To evaluate the effect of the overlapping area on the local bearing capacity of concrete, the experimental study was conducted on 6 concrete pull-out specimens. Based on the pull-out test, the parameter that net distance between headed bars was researched. The failure modes of specimens can be divided into two types. The first failure mode was marked by the formation of the dovetail slot structure during the failure process, and the second failure mode was characterized by the formation of through cracks in the cross section of specimens. The pull-out test results show that the local bearing capacity of concrete decreases firstly with the increase of net distance and then increases with the increase of net distance. Therefore, the relationship between the ratio of net distance to the side length of headed bars and the percentage decrease value of the local bearing capacity were given for the two segments. In addition, the critical value of the two segments was also analyzed and the corresponding formulas were also proposed. In order to verify the accuracy of formulas for the two segments, the test data from the similar pull-out tests with two or three headed bars were collected. And the calculation was recalculated according to the method proposed in this paper. Based on the ratio of the test data to the calculated values, the average value, standard deviation, and coefficient of variation are 1.08, 0.12, and 0.11 for the descending segment, respectively. And the values are 1.21, 0.22, and 0.18 for the rising segment, respectively. It is proved that there is a high accuracy for the formulas and the calculation method for the local bearing capacity of concrete under the interaction of headed bars was established.
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