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111.
Many closely located adjacent buildings have suffered from pounding during past earthquakes because they vibrated out of phase.Furthermore,buildings are usually constructed on soil;hence,there are interactions between the buildings and the underlying soil that should also be considered.This paper examines both the interaction between adjacent buildings due to pounding and the interaction between the buildings through the soil as they affect the buildings’ seismic responses.The developed model consists of adjacent shear buildings resting on a discrete soil model and a linear viscoelastic contact force model that connects the buildings during pounding.The seismic responses of adjacent buildings due to ground accelerations are obtained for two conditions:fixed-based(FB) and structure-soil-structure interaction(SSSI).The results indicate that pounding worsens the buildings’ condition because their seismic responses are amplified after pounding.Moreover,the underlying soil negatively impacts the buildings’ seismic responses during pounding because the ratio of their seismic response under SSSI conditions with pounding to those without pounding is greater than that of the FB condition. 相似文献
112.
Bhadravathi Eswara Lokesh Zubaidah Aimi Abdul Hamid Takamitsu Arai Akihiko Kosugi Yoshinori Murata Rokiah Hashim Othman Sulaiman Yutaka Mori Kumar Sudesh 《洁净——土壤、空气、水》2012,40(3):310-317
Utilization of cheap renewable carbon feedstock for polyhydroxyalkanoate (PHA) production not only brings down its production cost but also ensures sustainability. The scope of this study was to evaluate the potential of sap extracted from felled oil palm trunk (OPT) as a novel inexpensive renewable carbon source for PHA production. OPT sap was found to be nutritionally rich and contained various fermentable sugars (5.5% w/v) as its major constituent. Termite gut isolate, Bacillus megaterium MC1 grew profoundly in mineral medium with OPT sap as carbon source and a cell density of 10.9 g/L was attained after 16 h of cultivation in shake flask cultures. A maximum poly‐3‐hydroxybutyrate [P(3HB)] content (% cell dry weight; CDW) of 30 wt% and a P(3HB) concentration of 3.28 g/L was recorded. Additionally, OPT sap extracted from younger tree trunks with prolonged storage had higher sugar content (10.8% w/v) and, when used as a growth medium without the addition of any nutrients, supported bacterial growth comparable to commercially available media. 相似文献
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114.
Laboratory soil piping and internal erosion experiments: evaluation of a soil piping model for low‐compacted soils 下载免费PDF全文
Garey A. Fox Rachel G. Felice Taber L. Midgley Glenn V. Wilson Abdul‐Sahib T. Al‐Madhhachi 《地球表面变化过程与地形》2014,39(9):1137-1145
Mechanistic models have been proposed for soil piping and internal erosion on well‐compacted levees and dams, but limited research has evaluated these models in less compacted (more erodible) soils typical of hillslopes and streambanks. This study utilized a soil box (50 cm long, 50 cm wide and 20 cm tall) to conduct constant‐head, soil pipe and internal erosion experiments for two soils (clay loam from Dry Creek and sandy loam from Cow Creek streambanks) packed at uniform bulk densities. Initial gravimetric moisture contents prior to packing were 10, 12 and 14% for Dry Creek soil and 8, 12, and 14% for Cow Creek soil. A 1‐cm diameter rod was placed horizontally along the length of the soil bed during packing and carefully removed after packing to create a continuous soil pipe. A constant head was maintained at the inflow end. Flow rates and sediment concentrations were measured from the pipe outlet. Replicate submerged jet erosion tests (JETs) were conducted to derive erodibility parameters for repacked samples at the same moisture contents. Flow rates from the box experiments were used to calibrate the mechanistic model. The influence of the initial moisture content was apparent, with some pipes (8% moisture content) expanding so fast that limited data was collected. The mechanistic model was able to estimate equivalent flow rates to those observed in the experiments, but had difficulty matching observed sediment concentrations when the pipes rapidly expanded. The JETs predicted similar erodibility coefficients compared to the mechanistic model for the more erodible cases but not for the less erodible cases (14% moisture content). Improved models are needed that better define the changing soil pipe cross‐section during supply‐ and transport‐limited internal erosion, especially for piping through lower compacted (more erodible) soils as opposed to more well‐compacted soils resulting from constructing levees and dams. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
115.
Spatial analysis of daily rainfall intensity and concentration index in Peninsular Malaysia 总被引:1,自引:0,他引:1
This study presents the spatial analysis of daily rainfall intensity and concentration index over Peninsular Malaysia. Daily rainfall data from 50 rainfall stations are used in this study. Due to the limited number of stations, the geostatistical method of ordinary kriging is used to compute the values of daily rainfall concentration and intensity and to map their spatial distribution. The resultant analysis of rainfall concentration indicated that the distribution of daily rainfall is more regular over the west, northwest and southwest regions compared to the east. Large areas of the eastern Peninsula display an irregularity in distribution of daily rainfall. In terms of number of rainy days, analysis of daily rainfall confirms that a large number of rainy days across the Peninsula arise from low-intensity events but only contribute a small percentage of total rain. On the other hand, a low frequency of rainy days with high-intensity events contributes the largest percentage of total rain. The results indicated that the total rain in eastern areas is mainly contributed by the high-intensity events. This finding explains the occurrence of a large number of floods and soil erosions in these areas. Therefore, precautionary measures should be taken earlier to prevent any massive destruction of property and loss of life due to the hazards. These research findings are of considerable importance in providing enough information to water resource management, climatologists and agriculturists as well as hydrologists for planning their activities and modelling processes. 相似文献
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Ahmed Nasir Bodrud-Doza Md. Islam S. M. Didar-Ul Choudhry Manzoor Ahmad Muhib Md. Iftakharul Zahid Anwar Hossain Shahadat Moniruzzaman Md. Deb Nipa Bhuiyan Md. Abdul Quaiyum 《中国地球化学学报》2019,38(3):440-455
Acta Geochimica - To investigate the hydrogeochemical characteristics of groundwater 23 shallow, 30 intermediate and 38 deep wells samples were collected from Sylhet district of Bangladesh, and... 相似文献
118.
Ehtisham Abdul Rehman 《Arabian Journal of Geosciences》2017,10(4):88
Reduced amplitude and distorted dispersion of seismic waves caused by attenuation, especially strong attenuation, always degrade the resolution of migrated images. To improve seismic imaging, attenuation must be compensated. This study addresses the factors causing seismic attenuation in Jati Block. Jati Block lies in Lower Indus Basin, Pakistan, approximately 25 mi north of the offshore Indus. Method used for Q factor is empirical equation method. Q factor correlation indicates that there are three major zones of attenuation in Jati block, i.e., zone I (surface to top Khadro), zone II (Upper Goru Formation), and zone III (Lower Goru Formation). Lowest Q value is in zone I, followed by zone II and zone III, respectively. Commonly, Khadro Formation (Basalt) of Paleocene and saucer-shaped igneous intrusion is considered as sources of attenuation. However, surprisingly, Khadro Formation of Paleocene and saucer-shaped igneous intrusion is zone of minimum attenuation and causes minimal transmission loss. Anisotropy analysis is performed to determine cause of attenuation within these zones. Thomson anisotropic parameters are computed for vertical wells using Backus averaging algorithm. These parameters are calibrated using sonic scanner data available for one well. Correlation of Q factor curve with mud log suggests that loose, unconsolidated sands and sand-shale layering are sources of attenuation within zone I. Attenuation in this zone is mostly due to fluid motion relative to the framework of loosely packed grains. Major lithology of Upper Goru Formation is marl. It is a slow formation, and in this formation, P wave loses energy to the formation in what is known as leaky P mode (sonic logging) and is dispersive (seismic). Epsilon (?) value is greater than almost 0.02 throughout Lower Goru Formations, indicating that this formation is strongly anisotropic. Fluctuation of epsilon (?) in Lower Goru Formation also suggests that this formation is causing layer-induced anisotropy. This layer-induced anisotropy in Lower Goru Formation added by dispersive and slow nature of Upper Goru Formation causes rapid attenuation. 相似文献
119.
Mokhtar Ernieza Suhana Pradhan Biswajeet Ghazali Abd Halim Shafri Helmi Zulhaidi Mohd 《Natural Hazards》2017,87(2):1125-1146
Natural Hazards - Discharge is traditionally measured at gauge stations located at discrete positions along the river course. When the volume of water discharge is higher than the river bank,... 相似文献
120.
Yawar Hussain Sadia Fida Ullah Muhammad Babar Hussain Abdul Qayyum Aslam Gulraiz Akhter Hernan Martinez-Carvajal Martin Cárdenas-Soto 《Environmental Earth Sciences》2017,76(2):84
The area of Thal Doab is located in the Indus Basin and is underlain by a thick alluvial aquifer called the Thal Doab aquifer (TDA). The TDA is undergone intense hydrological stress owing to rapid population growth and excessive groundwater use for livestock and irrigated agricultural land uses. The potential impact of these land uses on groundwater quality was assessed using a DRASTIC model in a Geographic Information System environment. Seven DRASTIC thematic maps were developed at fixed scale and then combined into a groundwater vulnerability map. The resultant vulnerability index values were grouped into four zones as low, moderate, high and very high. The study has established that 76% of the land area that is underlain by the TDA has a high to very high vulnerability to groundwater contamination mainly because of a thin soil profile, a shallow water table and the presence of soils and sediments with high hydraulic conductivity values. In addition, only 2 and 22% of the total area lie in low and moderate vulnerability zones, respectively. The outcomes of this study can be used to improve the sustainability of the groundwater resource through proper land-use management. 相似文献