Concrete Technology and Practice Analysis

Question: Describe how the properties of the concrete mixes can determine the performance characteristics, use spreadsheet properties (i. e., ability to be placed into congested reinforcement sections, ability to resist compressive loads and bending moments and ability to endure C2 exposure classification). Answer: For the desired performance characteristics, the properties of the concrete mixes given in the spreadsheet can be determines after checking the: - 1. Ability to be placed in to congested reinforcement sections: - As per the spreadsheet freshly prepared concrete have low yield stress and high viscosity. As yield stress measures the amount of energy with which concrete flows. Considered that the concrete flows easily under its own weight that is due to gravity, so its yield stress should be very low. Thickness measures the resistance of crisply arranged cement to stream because of inside grating. So the solid ought to have high thickness so as to suspend total particles in a homogenous way inside the solid blend with no isolation, over the top dying, and unnecessary air movement (Mehta and Monteiro, 2005). However because of higher powder substance concrete drains not exactly the ordinary droop cement and it can likewise prompt shrinkage splitting on the off chance that it is not appropriately ensured and cured, especially in flatwork. Workability characteristics of freshly prepared concrete are measured in four ways:- Flowability:- This property measured using slump flow and used to represents the ability of concrete to flow into forms through densely reinforced and complex structural elements under its own weight but there is a drawback with this property that it does not suggest that all concrete gets leveled by itself. Passability (resistance to blocking):- This property measures the ability of concrete to flow under its own weight through confined spaces, such as narrow spacing between reinforcing bars and also fills open spaces in the formwork without any segregation or blocking (Naghoj and Abdel-Rahmna, 2004). Stability or segregation resistance: - This property of the concrete is its capacity to sustain a homogenous composition in a fresh state during and after the process of transport and placing. This includes both static and dynamic stability. 2. Ability to resist compressive loads and bending moment: - Concerning the role of the reinforced concrete, it has more number of advantages over the masonary, it has the ability to resist the tension and also the compression and consequently it has the ability to resist the bending. As the given data in the spreadsheet shows that it can provide the sufficient strength to concrete structure according to the standards. The vault and the dome are, of course, compressive form active structures, the meaning of that is it never subjected to the bending moment because for the specific load pattern which is valid for form active shapes only (Neville and Brooks, 1994). Ability to endure C2 exposure classification: Corrosion is presumably the most well-known unmistakable indication of decay in outside cement. It has huge security suggestions when the compelling region of fortifying steel is decreased by transformation to rust that causes spalling of solid spread. Basic wellbeing is more basic for prestresses concrete in view of the more noteworthy helplessness of prestressing gauges to consumption and potential for disastrous disappointments if these strands are traded off via flesh. The presentation classes fdor conditions that need erosion security of fortification are: C0 (Not Applicable) This type of concrete will be dry and will be protected from moisture in service. C1 (Moderate) This type of concrete will exposed to external source of chlorides but will be exposed to the moisture in the service. C2 (Severe) In this type the concrete is more exposed to chlorides and also to the moisture in services from deicing chemicals, salt, seawater, spray and brackish water from these sources. (Schneider and Chen, 2005) For Class C2 the outline expert is told to pay consideration on the unmistakable front of cement to the fortifying steel. For prestressed concrete, the Code particularly requires that the spread be expanded by half. In fortified cement expanding the spread should be adjusted with the potential for expanded and more extensive splits. Conclusion In concluding all of the above facts I came to the conclusion that the data on which the analysis has been done is based on the spreadsheet that has been provided. According to the choice of the concrete mixes in the given file the choice of mix B is choosen. There are certain properties like the properties which are used to determine the performance characteristics based on the air storage, cylinder and slump. The selection of the concrete mix B will provide enough strength to the structure of the buildings and bridge deck will provide enough protection against sulphate and help the building to stay for long time. References Abdel-Razik. 2004. Coating protection of loaded R.C. columns against elevated temperature, in: International Conference, Future Vision and Challenges for Urban Development, Cairo, Egypt, Kodur, L.A. Bisby, M.F. 2004 Green, Fire endurance of FRP-strengthened reinforced concrete columns, in: Proceedings of the Fourth International Conference on Concrete Under Severe Conditions, Seoul, Korea. McCoy, W. J. 2002 Mixing and curing water for concrete.Significance of tests and properties of concrete and concrete-making materials,STP 169-A. pp.515521. Philadelphia, PA: American Society for Testing and Materials. Mehta, P. K. and Monteiro, P.2005.Concrete: microstructure, properties, and materials. 3rd ed, 135136. New York: McGraw-Hill Professional. Naghoj, N. M. and Abdel-Rahmna, N. 2004 Enhancing the performance of concrete subjected to salty seawater.Admixtures enhancing concrete performance,the international conference, Dundee, Scotland, UK. London: Thomas Telford. pp.3540. Neville, A. M. and Brooks, J. J.1994.Concrete technology, England: Longman Scientific and Technical.