The development of earthquake engineering in China is described into three stages.The initial stage in 1950's -1960's was marked with the initiation of this branch of science from its creation in the first national 12-year plan of science and technology by specifying earthquake engineering as a branch item and IEM was one participant. The first earthquake zonation map and the first seismic design code were soon completed and used in engineering design. Site effect on structural design and site selection were seriously studied. The second stage marked with the occurrence of quite a few strong earthquakes in China, from which many lessons were learned and corresponding considerations were specified in our design codes and followed in construction practice. The third stage is a stage of disaster management, which is marked by a series of government documentations, leading by a national law of the People's Republic of China on the protecting against and mitigating earthquake disasters adopted at the meeting of the Standing Committee of the National People's Congress of the People's Republic of China in 1997, and then followed by some provincial and municipal laws to force the actions outlined in the national law. It may be expected that our society will be much more safer to resist the attack of future strong earthquakes with less losses. Lastly, possible future developments are also discussed.Keywords: earthquake engineering in China; stage of development; disaster management; future developments EARTHQUAKE ENGINEERING AND ENGINEREING VIBRATION Vol.1 2

A new shell finite element method (FEM) model with an equivalent boundary is presented for estimating the response of a buried pipeline under large fault movement. The length of affected pipeline under fault movement is usually too long for a shell-mode calculation because of the limitation of memory and time of computers. In this study, only the pipeline segment near fault is modeled with plastic shell elements to study the local buckling and the large section deformation in pipe. The material property of pipe segment far away from the fault is considered as elastic, and nonlinear spring elements at equivalent boundaries are obtained and applied to two ends of shell model. Compared with the fixed-boundary shell model, the shell model with an equivalent boundary proposed by the study can remarkably reduce the needed memory and calculating time.

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Human activities have greatly accelerated the input of nitrogen into waters, resulting in water quality degradation. Facing the water crisis of nitrogen pollution, the state of surface water in arid areas needs close attention. Although numerous studies have indicated that waters’ nitrogen is often impacted by land use covers, the correlation between the two remains obscure. This paper explored the spatial relationship between anthropogenic activity and waters’ nitrogen on the eastern Loess Plateau, based on the Geographic Information System (GIS) spatial analysis using land use covers. There were 3 human land use types and 2 nitrogen indices used to assess the rivers’ state at the watershed scale. The results showed that rivers’ nitrogen was closely associated with human land use covers. Nitrogen pollution was most serious in urban areas. This study provided new evidence for the relationship between anthropogenic activities and river ecology. The findings may be helpful for policymakers to make strategic decisions of water resource management and land use planning in arid areas.

Characteristics of near-fault vertical and horizontal ground motion from 2008 Wenchuan earthquake are investigated in this paper. Records from 40 strong motion stations along the Beichuan-Yingxiu fault with fault distance smaller than 120km are used as database. Based on the analysis of peak ground acceleration, peak velocity, spectra acceleration and spectra ratio of vertical to horizontal ground motion, the following conclusions can be made: (1) Hanging wall effects are shown in PGA for near-fault ground motions within 60 km to the surface rupture, the empirical model results in up to a 30%∼40% increase in peak horizontal and vertical accelerations on the hanging wall over the distance range of 3 to 60 km relative to the median attenuation for the Wenchuan earthquake. The peak acceleration residuals on the hanging wall appear to be biased to positive values whereas the residuals of footwall sites are negative. The EW component of horizontal accelerations is larger than the NS component and attenuates more slowly. (2) There is a lack of long period component in near-fault ground motion of Wenchuan earthquake, the value of spectrum acceleration decreases rapidly in the long period range. The maximum spectrum acceleration is only 0.5 g even at locations very close to the main causative fault at period 1.0 s. Large distinctions are shown in the distribution of acceleration spectrum ratio (Vertical/Horizontal) for near-source ground motion at longer periods (T =0.2 s, 0.5 s, 1.0 s) with respect to short periods (T =0.05 s, 0.1 s).(3) High intensity of UD component is shown for near-fault ground motion, the PGA ratio (Vertical/Horizontal) can be as large as 1.4. High intensity of UD component is more obvious on the hanging wall, and the PGA ratios on the hanging wall are much larger compared with the footwall. For some near-fault records, the acceleration spectral ratio (Vertical/Horizontal) can even be larger than 1.5. It can also be concluded that the spectral ratio decreases with the increasing of fault distance at short periods (<0.1 s).

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Summary:In this research work, a low-temperature examination method for scanning electron microscopy (SEM) is introduced. A water-absorbable polymer material, the sulfonated polyethylene (SPE) ion-exchange hollow fiber membrane, was used for the experiments. With this lowtemperature technique, the wet morphology of the waterabsorbable sulfonated polyethylene hollow fiber membrane was revealed. The results obtained from this investigation offer some important information to explain the behavior of the SPE hollow fiber membranes when they are applied in pervaporation separation of water/ organic solvent mixtures, such as water/ethylene glycol, water/ethanol, and so forth.