Sub-grade soils of lateritic origin encountered in the construction of highway embankments in various regions of India, often comprise intrusions of soft lithomargic soils that result in large settlements during const...Sub-grade soils of lateritic origin encountered in the construction of highway embankments in various regions of India, often comprise intrusions of soft lithomargic soils that result in large settlements during constructions, and differential settlements at later stages. This necessitates the use of appropriate soil improvement techniques to improve the load-carrying capacity of pavements. This work deals with accelerated consolidation of un-reinforced and coir-rein- forced lateritic lithomargic soil blends, provided with three vertical sand drains. The load-settlement characteristics were studied for various preloads ranging from 50 kg (0.0013 N/mm2) to 500 kg (0.013N/mm2) on soil specimens prepared in circular ferro-cement moulds. It was observed that at lower preloads up to 200kg, across the blends, the relative increase in consolidation (Rct) for randomly reinforced soil with vertical drains was sig-nificantly higher than that of un-reinforced soil without vertical drains, with an average value of 124.8%. Also, the Rct for un-reinforced soil with vertical drains was quite higher than that of un-reinforced soil without vertical drains, with an average value of 103.9%. In the case of higher preloads, the Rct values for randomly reinforced soil with vertical drains were moderate with an average value of 30.88%, while the same for un-reinforced soil with vertical drains was about 20.4%. The aspect-ratio of coir fibers used was 1:275.展开更多
ZnO thin films were synthesised by a new method which uses polyvinyl alcohol （PVA） as the polymer precursor. The films are annealed at different temperatures and for different annealing times. The structural paramet...ZnO thin films were synthesised by a new method which uses polyvinyl alcohol （PVA） as the polymer precursor. The films are annealed at different temperatures and for different annealing times. The structural parameters, like grain size, lattice constants, optical band gap, and Urbach energy, depend on the annealing temperature and time. All the films possess tensile strain, which relaxes as the annealing temperature and time increase. The photoluminescence （PL） spectra contain only ultraviolet （UV） peaks at low temperature, but as the annealing temperature and time increase, we observe peaks at the blue and green regions with a variation in the intensities of these peaks with annealing temperature and time.展开更多
文摘Sub-grade soils of lateritic origin encountered in the construction of highway embankments in various regions of India, often comprise intrusions of soft lithomargic soils that result in large settlements during constructions, and differential settlements at later stages. This necessitates the use of appropriate soil improvement techniques to improve the load-carrying capacity of pavements. This work deals with accelerated consolidation of un-reinforced and coir-rein- forced lateritic lithomargic soil blends, provided with three vertical sand drains. The load-settlement characteristics were studied for various preloads ranging from 50 kg (0.0013 N/mm2) to 500 kg (0.013N/mm2) on soil specimens prepared in circular ferro-cement moulds. It was observed that at lower preloads up to 200kg, across the blends, the relative increase in consolidation (Rct) for randomly reinforced soil with vertical drains was sig-nificantly higher than that of un-reinforced soil without vertical drains, with an average value of 124.8%. Also, the Rct for un-reinforced soil with vertical drains was quite higher than that of un-reinforced soil without vertical drains, with an average value of 103.9%. In the case of higher preloads, the Rct values for randomly reinforced soil with vertical drains were moderate with an average value of 30.88%, while the same for un-reinforced soil with vertical drains was about 20.4%. The aspect-ratio of coir fibers used was 1:275.
文摘ZnO thin films were synthesised by a new method which uses polyvinyl alcohol （PVA） as the polymer precursor. The films are annealed at different temperatures and for different annealing times. The structural parameters, like grain size, lattice constants, optical band gap, and Urbach energy, depend on the annealing temperature and time. All the films possess tensile strain, which relaxes as the annealing temperature and time increase. The photoluminescence （PL） spectra contain only ultraviolet （UV） peaks at low temperature, but as the annealing temperature and time increase, we observe peaks at the blue and green regions with a variation in the intensities of these peaks with annealing temperature and time.
