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The increasing value of land and the limited availability of suitable sites for construction are greatly encouraging engineers to consider in situ improvement of weak soil deposits. To economically develop marginal sites a number of ground improvement techniques have been developed as stone columns, jet grouting, compaction grouting, short pile, dynamic compaction, lime stabilization etc. Stone column treatment is one of the most promising and favourable ground improvement techniques widely practiced all over the world. This paper presents a critical review of analytical, experimental, numerical and field studies on the aspect of ordinary and encased stone columns which have been published in the past three decades. Focus is on the recent advancement of encasing these columns with geosynthetic products to enhance their performance in load bearing capacity, decreasing the compressibility, accelerating and reducing the consolidation settlement. Another advantage of encasement is to prevent excessive bulging, squeezing of stone into soft soil. This paper presents installation methods, failure modes of stone columns and brief review of previous researches.

Effective utilization of Daylighting Systems (DLS) in buildings has the potential to maximize the benefits of daylighting, reduce energy consumption, and achieve a quality building environment for the users. Even though the number of possible alternatives that can be generated for integrating DLS in buildings is immense, the number of DLS alternatives simulated and analyzed in previous research has been fairly limited. Therefore, this paper focuses on expanding the number of design alternatives to be simulated and analyzed for integrating DLS individually and collectively at both individual zones and in the whole building, including at different orientations, in order to better inform and enrich design decisions for selecting the best alternatives of DLS that can achieve the highest energy performance for office buildings in a hot climate zone such as Egypt. Daylighting and Energy simulation are conducted for these alternatives, along with visual and comfort analysis.

The results of conducting a comparative study of various DLS in Office Buildings in Egypt include identifying optimal alternatives for improving energy efficiency. Results indicate that HSD and HST, whether individually or collectively, can achieve the highest savings, with a reduction of 40% in the energy consumption of cooling and lighting, while HLE saves 38% and HBI saves 24% of the energy consumption for cooling and lighting. The paper concludes with a developed guide to be used by building designers at the conceptual design stages to improve energy efficiency of buildings by selecting and integrating the most appropriate DLS based on building conditions and designers’ preferences of façade design.

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Numerous urban seismic vulnerability studies have recognized pounding as one of the main risks due to the restricted separation distance between neighboring structures. The pounding effects on the adjacent buildings could extend from slight non-structural to serious structural damage that could even head to a total collapse of buildings. Therefore, an assessment of the seismic pounding hazard to the adjacent buildings is superficial in future building code calibrations. Thus, this study targets are to draw useful recommendations and set up guidelines for potential pounding damage evaluation for code calibration through a numerical simulation approach for the evaluation of the pounding risks on adjacent buildings. A numerical simulation is formulated to estimate the seismic pounding effects on the seismic response demands of adjacent buildings for different design parameters that include: number of stories, separation distances; alignment configurations, and then compared with nominal model without pounding. Based on the obtained results, it has been concluded that the severity of the pounding effects depends on the dynamic characteristics of the adjacent buildings and the input excitation characteristics, and whether the building is exposed to one or two-sided impacts. Seismic pounding among adjacent buildings produces greater acceleration and shear force response demands at different story levels compared to the no pounding case response demands.

This study proposed Carbon fiber reinforced polymers (CFRP) as additional transverse reinforcement at the
critical zones of concrete filled steel tubular (CFST). An experimental study consisted of five main sets of specimens
representing the ends of columns, such as those merging in through beam-column connections, was conducted. Each
main set of specimens investigated the behavior of the concrete core for a specific case of CFST or CFRP wrapped
CFST (CFCFST), and each main set comprised three similar specimens to get more accurate results. All specimens
were 160 mm external diameter and 320 mm height and had the same concrete grade. The thicknesses of the steel tubes
used were 2 and 3mm. The numbers of (CFRP) layers used were one and two layers. The results showed that one and
two CFRP outer layers added to CFST greatly improved the concrete compression. Response showed 29% and 54%
increase in the concrete core compressive strength, respectively. The increase in the steel tube thickness from 2mm to 3
mm caused 20% increase in the concrete core compressive strength. A new analytical model with a sufficient accuracy
was driven to predict the concrete core strength for both CFST and CFCFST cases.

There is a growing interest among architects to allow for a huge amount of daylighting inside office buildings as a way of achieving user’s visual comfort, however, this result in high energy consumption due to the high solar gain. Intelligent window techniques are considered a suitable solution for this issue due to their ability to change their main functional parameters based on the changing environmental situations and therefore contribute to reducing energy consumption. This paper reviews various types of glazing techniques and conducts a comparative study on 12 glazing techniques by measuring their performance on different facades of 1000 sq. m office building using Energy plus 8.6 simulation software (WWR 40%). Thus, guiding the selection of the best glazing technique for each facade.
Studying the performance of each technique on single façade showed that the best glazing technique on the east and west directions were “Electrochromic glazing (EC) with low SHGC” which allowed for a reduction of 32.18% and 32.45% respectively. While the “EC glazing with medium SHGC” reached 31.91% reduction when applied on the south facade. On the other side, by applying each technique on the four facades together, the best cooling reduction of almost 49% was achieved by using “Triple with suspended Low-E film” glazing technique.

Seismic vulnerability assessments of buildings after several earthquakes have confirmed that the pounding could be one of the key threats. The pounding among series of neighbouring building structures throughout earthquakes exerts repeated strikes on each other that could be a reason for structural damages ranging from light damage to even collapse. So, the main objectives are to provide constructive suggestions for code calibration through a numerical simulation for the estimation of the pounding risks on series of neighbouring buildings separated by minimum code-specified separation. A numerical simulation and FE analysis are developed to estimate the influence of pounding on the seismic response demands of adjacent buildings. The collision effects on 3-, 6- and 12-stories adjacent buildings are studied for different separation distances and alignment configurations and compared with a nominal model without pounding considerations. Based on the obtained results, it is concluded that the seriousness of the impact effects is influenced by the vibration characteristics of the adjacent buildings, the input excitation characteristics and whether the building is exposed to one- or two-sided impacts. There are additional loads caused by the pounding which leads to additional shear forces and acceleration at different story levels that do not appear in the no-pounding case.

This paper introduces a sensing and stimulation system to transfer the electromyogram (EMG) signal from one limb to another, aiming to enable self-electro-physical therapy. The presented technique depends on sensing EMG signal from one limb muscle and, simultaneously, stimulating the corresponding muscle in the other limb by this signal. The technique has been implemented on a standalone cheap microcontroller. The sensing and stimulating circuits have been implemented using off-shelf components. The delivery of the stimulating signal has been done noninvasively through surface electrodes.