Analysis of Office-Teaching Comprehensive Buildings Using a Modified Seismic Performance Evaluation Method

Current building design codes allow the appearance of structural and nonstructural damage under design basis earthquakes.The research regarding probabilistic seismic loss estimation in domestic building structure is urgent.The evaluation in this paper is based on a 11-story reinforced concrete office building,incremental dynamic analysis(IDA)is conducted in Perform 3D program using models capable to simulate all possible limit states up to collapse.Next,the probability distribution of post-earthquake casualties,rebuild costs repair costs and business downtime loss are calculated in PACT software for the studied building considering the modified component vulnerability groups and population flow models.The evaluation procedure can also shed light on other types of buildings in China.For non-typical functional building structures,this article proposes to build a finite element model of structural components and to classify the vulnerability groups based on the construction drawings,and to supply and improve the vulnerability library of appendages in FEMA P-58 according to the actual situation.In this way,the application scope of building seismic performance evaluation can be expanded.

Revisiting the driving force underlying Chinese PM_(2.5)emissions:From the two perspectives of GVC and IDA

The depth and breadth of participation in the global value chain(GVC)significantly impacts a country's fine particulate contamination(PM_(2.5))emissions.First,based on the GVC accounting framework,the sources of PM_(2.5) emissions in China between 1990 and 2015 are identified and investigated considering production-side,consumption-side,and export-implied pollution.Then,index decomposition analysis(IDA)of emissions is conducted to further investigate the changes in and causes of air pollution in China.Throughout the analytical process,differences between the PM_(2.5) emissions in two time periods-one of rapid economic growth and another of the“new normal”economy-are compared.The results demonstrate that:China is embedded in high pollution links of GVCs;China transfers pollution to third-parties by importing intermediate products from resource-intensive countries in the global production system;extensive economic growth caused an increase in China's total PM_(2.5) emissions,but cleaner production technology can reduce the emissions intensity.Industrial restructuring under the“new normal”has increased China's short-term PM_(2.5) emissions intensity.These results suggest that China should optimize and upgrade its domestic economic structure and transform its export growth mode to deliver high added value and low pollution.Further,it should prioritize cooperation between the upstream and downstream value chain and accelerate the upgrading of its consumption structure in this new era.

A Coupled Soil-Fluid-Structure Simulation of the Near-Field Earthquake Effects on Gravity Type Quay-Walls

This study focuses on non-linear seismic response of concrete gravity quay-wall structures subjected to near-fault ground motions, a subject which seems not to have received much attention in the literature. A two-dimensional coupled fluid-structure-soil finite element modelling is employed to obtain the quay-wall response. The seawater medium is represented by acoustic type, potential based fluid elements. The elasto-plastic behavior of the soil medium is idealized using Drucker-Prager yield criterion based on associated flow rule assumption. Four nodded plane strain elements are used to model the concrete wall, foundation, subsoil, backfill and seabed zones. Fluid Structure Interface （FSI） elements are considered between the seawater interfaces with the quay-wall and the seabed. Frictional contact elements are employed between the wall and soil interfaces. The numerical model is validated using field measurements available for permanent drifts in a quay-wall damaged during Kobe earthquake. Reasonable agreements are obtained between the model predictions and the field measurements. Non-linear seismic analyses of the selected quay-wall subjected to both near-fault and far-fault ground motions are performed. An incremental dynamic analysis approach （IDA） is used. In general, at least for models examined in the current study, the gravity quay-walls are found to be more vulnerable to near-field, in comparison with the corresponding far-field, earthquakes.

Seismic performance of moment resisting steel frame subjected to earthquake excitations

This study presents static and dynamic assessments on the steel structures. Pushover analysis （POA） and incremental dynamic analysis （IDA） were run on moment resisting steel frames. The IDA study involves successive scaling and application of each accelerogram followed by assessment of the maximum response. Steel frames are subjected to nonlinear inelastic time history analysis for 14 different scaled ground motions, 7 near field and 7 far field. The results obtained from POA on the 3, 6 and 9 storey triangular lateral loading. Uniform loading shows that the steel frames show consistent results for both uniform and steel frames exhibits higher base shear than the triangular loading. The IDA results show that the far field ground motions has caused all steel frame design within the research to collapse while near field ground motion only caused some steel frames to collapse. The POA can be used to estimate the performance-based-seismic-design （PBSD） limit states of the steel frames with consistency while the IDA seems to be quite inconsistent. It is concluded that the POA can be consistently used to estimate the limit states of steel frames while limit state estimations from IDA requires carefully selected ground motions with considerations of important parameters.