The goal of this work is to investigate the seismic behaviour of plan-asymmetric structures by considering the least seismic-resistant directions and the spatial features of the seismic event. New tools for the analys...The goal of this work is to investigate the seismic behaviour of plan-asymmetric structures by considering the least seismic-resistant directions and the spatial features of the seismic event. New tools for the analysis of the seismic behaviour of plan-asymmetric structures are herein presented and the concepts of ＂Polar Spectrum＂ and limit domains are discussed. In particular, the capacity of the structure is described by using the limit domains based on the Non Linear Static Procedures, while the seismic demand is analysed by introducing a new representation of the spectral response. This representation is based on the construction of a spectral surface obtained by the spectral seismic response for different in-plan directions and the in-plan projection of this surface is herein defined ＂Polar Spectrum＂. The obtained results for two benchmark structures, verified by means of non-linear incremental dynamic analyses, have pointed out that non-linear static analyses, carried out for different in-plan directions of the incoming seismic action, have allowed us to accurately evaluate the least seismic resistant directions.展开更多
Black phosphorus has a strong Raman anisotropy on the basal and cross planes dueto its orthorhombic crystal structure. However, almost all the studies on blackphosphorus’ anisotropy focus on basal plane with the cros...Black phosphorus has a strong Raman anisotropy on the basal and cross planes dueto its orthorhombic crystal structure. However, almost all the studies on blackphosphorus’ anisotropy focus on basal plane with the cross plane neglected. Here,we performed a systematic angle-resolved polarized Raman scattering on both thebasal and cross planes of black phosphorus and obtained its integral Raman tensors.It is discovered that when the polarization direction of excitation light is alongdifferent crystal axes, the Raman intensity ratio (Ixx : Iyy: Izz) of A1g mode is 256:1:5.Besides, via calculation, it is confirmed that the strong Raman anisotropy mainlycomes from different differential polarizability alone different directions. Thisphenomenon is also observed when it comes to the A2g mode.展开更多
文摘The goal of this work is to investigate the seismic behaviour of plan-asymmetric structures by considering the least seismic-resistant directions and the spatial features of the seismic event. New tools for the analysis of the seismic behaviour of plan-asymmetric structures are herein presented and the concepts of ＂Polar Spectrum＂ and limit domains are discussed. In particular, the capacity of the structure is described by using the limit domains based on the Non Linear Static Procedures, while the seismic demand is analysed by introducing a new representation of the spectral response. This representation is based on the construction of a spectral surface obtained by the spectral seismic response for different in-plan directions and the in-plan projection of this surface is herein defined ＂Polar Spectrum＂. The obtained results for two benchmark structures, verified by means of non-linear incremental dynamic analyses, have pointed out that non-linear static analyses, carried out for different in-plan directions of the incoming seismic action, have allowed us to accurately evaluate the least seismic resistant directions.
基金support of this work is from the National Natural Science Foundation of China(Nos.91333207,61427901,61604178,91833301 and U1505252).
文摘Black phosphorus has a strong Raman anisotropy on the basal and cross planes dueto its orthorhombic crystal structure. However, almost all the studies on blackphosphorus’ anisotropy focus on basal plane with the cross plane neglected. Here,we performed a systematic angle-resolved polarized Raman scattering on both thebasal and cross planes of black phosphorus and obtained its integral Raman tensors.It is discovered that when the polarization direction of excitation light is alongdifferent crystal axes, the Raman intensity ratio (Ixx : Iyy: Izz) of A1g mode is 256:1:5.Besides, via calculation, it is confirmed that the strong Raman anisotropy mainlycomes from different differential polarizability alone different directions. Thisphenomenon is also observed when it comes to the A2g mode.
