Impact of Fire Extinguishing Techniques On Concrete Performance

The incidence of fire unfortunately occurs quite frequently in buildings. In some cases it causes collapse of the whole structure. Many researches focused on investigation of the effect of fire on concrete strength. Others focused on the effect of concrete constituents on the fire resistance. Our main aim in this study is to try to find the ideal method for extinguishing fire, with minimum damage on concrete performance. (Concrete will be subjected to fire in different cases and different variables).The test program in this study focused on the effect of economical methods of extinguishing on the performance of concrete. The parameters considered in this study were: Effect of time on concrete under fire (1 hour, 2 hours and 3 hours). Impact of fire on concrete mixed with admixtures (super plasticizers, air entraining, and set retarders). Effect of using different methods of extinguishing the fire,(air cooling, cold water, hot cooling, cement paste) on physical and mechanical properties of concrete performance. The study also considered investigation of the effect of fire on concrete with different types of cement (ordinary Portland cement and Sulphate resistant cement. It was noted that Schmidt hammer presents an effective tool in preliminary assessment of buildings for fire fighters. The use of Ultra sonic pulse velocity was also successful in evaluation of the degree of damage in concrete

Charity and Nationalism: The Case of ‘Abd Allah al-Nadim’s Islamic Philanthropic Society

My paper argues that charity can be used as a lens to examine nationalism. Due to the transformation of the institution of charity in late nineteenth-century Egypt new charities were developed. In the nineteenth century charity was changing due to the state centralization policies of Mehmed ‘Ali (r. 1805-48), who founded state-run shelters and soup kitchens and enacted prohibitions against begging. Later because of decentralization policies under Said Pasha (r.1854-1863) and Khedive Ismail (r.1863-1879), there was a move away from state control of charity, and the gradual erection of a number of private charitable associations that aimed to help the “public” poor. I look at how the evolving nineteenth-century institutions of charity, both changes under Mehmed ‘Ali and later under his successors, differed from the “pre-modern” period. Is nineteenth-century charity similar to early charity, in particular the ‘awqaf (endowments) of Mamluk elites that became a symbol of the rulers’ beneficence? What did donation and beneficence mean in late nineteenth-century Egypt? And did the new charitable associations of the late nineteenth century, that were not an individual endowment (waqf) or state-controlled charity, begin to use their power of beneficence to improve the social conditions of people with the goal to mold a particular type of Egyptian citizen? This connection between charity and the modeling of a better citizen will constitute a central theme of my argument. My research concentrates on one Islamic charity created around the period of the 1881-2 ‘Urabi revolution, which are the years that are considered as the coming of age of the Egyptian nationalist movement. As such, my project’s periodization falls between 1879 and 1892 in order to obtain a detailed picture of charity within the early Egyptian nationalist movement. It focuses on the Islamic Philanthropic Society (IPS), founded in 1879, by ‘Abd Allah al-Nadim. The IPS was a nationalist organization, where both Egyptian territorial nationalism and Islamic nationalism were at work, with a mission to educate young poor Egyptians against what was perceived to be a growing foreign hegemony caused by the British occupation. Specifically, I will study how the IPS evolved, how its charity was donated, how it was received and perceived by its recipients in the late nineteenth century. My work expands on the current literature by looking at the connections between charity and nationalism, rather than looking specifically at the school/education side of the IPS alone. Instead of the individual contributing for themselves, or establishing their own endowment, like the many waqfs created to fund a madrassa or a kuttab, the new charitable associations of the late nineteenth century could be erected as joint charitable ventures, working not only for spiritual “reward,” but for the betterment of citizens

Glass Fiber for Improved Behavior of Light Expanded Clay Aggregate Concrete Beams: An Experimental Study

Concrete developed from light expanded clay aggregate (LECA) and glass fiber has good performance, durability, and sustainability. Towards this, the experimental investigation was designed to study cubes, cylinders, and simply supported beams. Four mixtures had LECA volume of 0%, 75%, 85%, and 95% as coarse aggregate replacement and glass fiber content volume of 2% (N, L75, L85, and L95), and the other two mixtures had 75% LECA and glass fiber content of 1% and 1.5% (L75-F1 and L75-F1.5). Results compared to normal concrete showed the weight reduction of samples while adding more glass fiber caused slump reduction in contrast to LECA. Increasing glass fiber volume in the mixture had a negative influence on tensile strength while causing compressive strength enhancement. Moment resistance and energy absorption capacity of L85 were enhanced by 7.5% and 10.3%, respectively. For L75-F1 specimens, the beam stiffness and ductility were enhanced by 14.8% and 14.3%, respectively. &nbsp

Rheology Of Cement Paste Containning Chemical Admixtures

Understanding the Rheology of cement and water is a not a simple task since, thebehaviour of complicated system varies with time and there is still a great deal of work to bedone before, it is properly understood. In this study, we used a new simple and cheaptechnique to evaluate flow properties of cement paste .This technique is based on dropping aneedle from a constant height. The penetration depth is measured at different circumstances,different w/c ratios, different types of super plasticizer, and different percentage of admixturefor two types of cement types of cements OPC type V (CEMEX) and OPC type I (HELWAN)were considered in this study. Also, effect of retempering on penetration depth were alsoconsidered. Finally effect of variation of needle drop height was also considered. Thepenetration depth technique proved to be effective in monitoring the effect ofsuperplasticizer/cement ratio percentage, effect of time, manual remixing after 30 minutesand needle drop height on the rheological behavior of different types of cement paste, whichfurther proves the effectiveness of this method in evaluation of cement paste Rheology

Production of durable and cost effective sewer pipes using petroleum and industrial waste by-products

© The Authors, published by EDP Sciences, 2017. The Arabian Gulf environment has an adverse impact on concrete structures because of the high ambient temperature, humidity, salt contaminated dust, sea water and underground salts. As an innovative solution, reinforced modified sulfur concrete (MSC) pipes are recognized as a durable and economical solution for deterioration of pipelines. This work describes the manufacture and characterization of new MSC based on a cost effective sulfur modification process. Bitumen, a by-product from crude oil refining process was used to modify elemental sulfur and enhance its physical, mechanical properties, and mostly to increase its corrosive resistivity. The study has focused on optimizing the proportions of an offered MSC mixes that are composed of modified sulfur (MS) as a binder, crushed sand, dune sand and ladle furnace (LF) slag as aggregates, and ground granulated blast furnace slag (GGFBS) as a filler. To maximize the physical and mechanical properties of MSC sewer pipes, different mixtures were prepared and investigated. The optimum mix of MSC has a maximum compressive strength of 64 MPa, maximum splitting tensile strength of 4.5 MPa, maximum flexural strength of 21 MP, with a high corrosion resistance in acidic and salty environments

Single Photon Quantum Ranging: When Sequential Decoding Meets High Dimensional Entanglement

We consider the quantum ranging problem in the low noise level per mode and low reflectivity (high loss) regime. We focus on single photon transmission strategies and propose a novel approach that combines high dimensional time-bin entanglement at the transmitter with a carefully constructed sequential decision rule at the detector. Our analytical results establish the significant performance gains that can be leveraged from this approach in a range of operating parameters, as compared to the single photon classical approach, the two-mode squeezed vacuum ranging scheme proposed earlier, and even the block-based classical scheme. One can attribute this performance gain to 1) the ability of the high dimensional time-bin entangled signaling to offer a very fine range resolution with a single transmitted photon and 2) the ability of the sequential decision rule to minimize the average number of transmitted photon subject to a constraint on the probability of error. While our analysis is limited to the low energy/low noise regime, we conjecture that the proposed approach's superior performance extends to a wider range of scenarios which should motivate further analytical and experimental investigations.Comment: Submitted to NPJ Quantum information for peer revie

Glass Fiber for Improved Behavior of Light Expanded Clay Aggregate Concrete Beams: An Experimental Study

Concrete developed from light expanded clay aggregate (LECA) and glass fiber has good performance, durability, and sustainability. Towards this, the experimental investigation was designed to study cubes, cylinders, and simply supported beams. Four mixtures had LECA volume of 0%, 75%, 85%, and 95% as coarse aggregate replacement and glass fiber content volume of 2% (N, L75, L85, and L95), and the other two mixtures had 75% LECA and glass fiber content of 1% and 1.5% (L75-F1 and L75-F1.5). Results compared to normal concrete showed the weight reduction of samples while adding more glass fiber caused slump reduction in contrast to LECA. Increasing glass fiber volume in the mixture had a negative influence on tensile strength while causing compressive strength enhancement. Moment resistance and energy absorption capacity of L85 were enhanced by 7.5% and 10.3%, respectively. For L75-F1 specimens, the beam stiffness and ductility were enhanced by 14.8% and 14.3%, respectively.

Comparative study between aortic valve replacement through full sternotomy versus mini-sternotomy

Background: The superiority of minimally invasive aortic valve replacement (AVR) over the standard approach is the subject of ongoing research. The aim of this study was to compare the outcomes of AVR through full sternotomy versus mini-sternotomy. Methods:  We included 60 patients who had AVR; 30 patients underwent AVR through J- or T-shaped mini-sternotomy, and 30 patients had a full sternotomy. We included patients who had isolated AVR and excluded patients who had a concomitant cardiac procedure, redo surgery, or those who needed annular dilatation. All patients had aortic and right atrial cannulation for cardiopulmonary bypass. Study endpoints were operative times, postoperative complications and duration of ICU and hospital stays. Results: There were no differences between the two groups preoperatively. Cardiopulmonary bypass time was longer in the mini-sternotomy group (median: 100 (range: 65- 170) vs. 85 (55-160) min, respectively; p= 0.024). Operative time was non-significantly longer in the mini-sternotomy group 5 (4-6) hours vs. 4.5 (4-6) hours in the full sternotomy group (p=0.62). Ventilation time was 10 (4- 50) hours in the mini-sternotomy group vs. 14 (8- 45) hours in the full sternotomy group (p<0.001). ICU stay was shorter in the mini-sternotomy group (2 (1-6.5) vs. 2.5 (1-7) days, respectively, p= 0.014). The total mediastinal drainage was 100 (50 400) ml in the mini-sternotomy group vs. 275 (50- 1000) ml in the full sternotomy group (p= <0.001). There was no difference in wound infection (p= 0.35), tamponade (p˃0.99), and hemothorax (p˃0.99) between both groups. Conclusion: Mini-sternotomy AVR had longer cardiopulmonary bypass times; however, there were no differences in the postoperative complications compared to the full sternotomy approach. Mini-sternotomy could be a safe alternative approach to the full median sternotomy for aortic valve replacement

Durability of modified sulfur concrete in sewerage environment

This study verifies and validates the superiority of sulfur concrete (SC) over the ordinary Portland cement concrete (PCC) and sulfate-resistant concrete (SRC) in sewer harsh environments. A field study was performed in an actual sewage environment, specifically at the sewer’s gas and sludge environments. Performance of the PCC, SRC and two types of SC was assessed after 3, 6, 10, 18 and 24 months of exposure. Specimen’s durability was evaluated through physical appearance, change in weight and mechanical and hydraulic properties. The microstructure and the composition of the specimens were studied by means of scanning electron microscopy and X-ray diffraction. Attempts have been made to explain the mechanism of deterioration, the basic chemical interactions involved in the deterioration processes and the effect of such interactions on the concrete and reinforcing steel. It was found that SC is highly resistant to sewer environment compared to PCC and SRC, and that there was a significant weight loss of 8·0% and 13·6% in PCC and SRC, respectively, whereas a smaller weight loss of 2·2% was noticed in SC. This is consistent with the observed reduction in strength, increase in permeability and noticeable steel bar corrosion for the PCC and SRC relative to the SC

A proposal for a production line for the design and implementation of quality clothing for gymnastics in A.R.E

Gymnastics wear needs multiple specifications in terms of material and the proportion ‎of elasticity, as well as the designs in terms of players' comfort and the movements of ‎this game .In this research, an empirical research study is conducted for gymnastics ‎wear to increase its productivity rate in the national market and what are the obstacles ‎facing this industry and how to develop it and reach the international. ‎Some people see the design of gymnastics wear is a secondary idea or an aesthetic ‎form, while others see it as the fulcrum of the ‎entire development process in relation to ‎the manufacturing process and the cost ‎of production.‎So this research is based on studying everything related to these clothes from the ‎materials available in the national market, as well as suggesting 50 designs and ‎making a questionnaire to identify the ten most suitable designs for gymnastics, and ‎then implementing these designs with nationally available materials and determining ‎appropriate production methods for gymnastics wear.‎A summary of the research Findings• The local fabrics have what is suitable for the production of gymnastics wear.‎• Determination the appropriate production methods for gymnastics clothing have ‎been identified in terms of cutting, knitting and embroideries.‎The Recommendations:‎• Paying attention to the study of the Gymnastics wear of the sport of gymnastics ‎in the departments of clothes design at Arts Faculties• Paying attention to the choice of the materials of the Gymnastics wear and the ‎suitable design given their influence on the player’s movemen