Design of the Office Building of Nanjing Bussiness Group文献综述

文献综述

Literature Review INTRODUCTIONOur childhoods are littered with attempts to create a muddled, unattractive edifice out of plastic blocks purchased at the local hardware store. Despite the fact that this may not have motivated many of us to continue in the job path we have chosen,As civil engineers, we can empathize with and understand.In many ways, concrete structures resemble the lovely blocks we always admired.They had all been assembled. Despite the fact that our prior experiences have helped shape who we are now,As weve fought to protect these incredible structures, weve had the pleasure of admiring them from afar. a part of who we are as a people.On the other hand, the application of what is studied might provide a variety of options.Engineering is the only way to learn about and use these concepts.Lacking sufficient research alternatives, our ancestors built structures based on partial accumulated wisdom and the belief that the structure would remain enigmatic for millennia excessively high, disregarding the requirements, resulting in an abundance of old wonders of the world. It should be obvious by this point what the primary distinctions are, as well as the evolution of language across time.. In truth, the issue at hand is one of necessity, since it reached our desired value and saves us time; this is why we have a huge number of customers.Many buildings have been finished by this point, but just a few have proven to be structures of awe As we go, we notice that the previously stated blocks are actually columns, beams, and other structural elements.structural features such as floors, walls, and ceilings. We assemble or cast a vast number of provisions.Depending on the structural application, we can use them in the lab. These provisions are rules that must be adhered to in order to avoid ambiguity and protect the integrity of the system.consistent environmental and geological conditions are present throughout this region, ensuring uniformity elements. This may not be the case for countries or regions with a tiny population.Progress in materials research and development has come to a halt at this moment.They have demonstrated to us that they are a kind of crucial aspect in beating the clock and dealing with these differences in the time.When it comes to small countries or geographical areas, these traits might vary greatly. When it comes to materials research and advancement, this is where we are now.has shown us time and time again that they are an essential part of beating the clock and Adapting to the widening performance gap.RC, as a building material, is used extensively around the world because of its importance in the development of urbanization. It has a lot of pros and cons. For example, some advantages of armed concrete are: 1. Compared to other construction materials, RC has high compressive strength. 2. RC can withstand a great deal of tensile stress due to the reinforcement provided. 3. Fire resistance and weather. 4. Considered to be more robust building system than any other building system for RC. 5. Initially, RC, as liquid materials, can be formed in an almost unlimited range of shapes. 6. Less skilled labour to establish the structure, compared to using steel in the structure. On the other hand, some disadvantages: 1. Tensile strength up to ten compressive strength. 2. RC steps are mixing, casting, and processing, which undoubtedly have a significant impact on the final power. 3. The cost of models used for casting RC is quite higher. 4. Deflation causes crack expansion and loss of strengthThere are many topics to be presented such as: concrete materials and different environments that are exposed to concrete and durability, concrete durability in the global building code, distressed RC tradition structures, concrete cracks, corrosion, and causes of deterioration, and solutions for the treatment of these problems, for example concrete injectors, repair by concrete, repair and prevention of rust, especially cathodic protection, reinforcing bars made of fiber reinforced plastic (FRP). Developed countries spend a huge proportion of their annual infrastructure budgets on repairs, maintenance and replacement of present and new structures, which is a significant indication of deficiencies in past construction practices. Graduation Project (Thesis) Opening Report２．Problems to be solved in this topic and research methods (pathways) to be adopted:Concrete Problems and Their SolutionsBleedingExcess water seeps through the surface of concrete when heavier constituents, such as aggregates and cement, settle. Because the evaporation rate and temperature arent adequate, the water droplets will keep emerging, resulting in excessive bleeding. Bleeding is a common occurrence during the curing process of concrete, however excessive bleeding can have a detrimental effect on the concretes strength.Ways to reduce bleeding:1.Strictly maintaining water to cement ratio.2.Adding sand of finer particles.3.Supplementary cementitious materials to increase water absorption.4.Adding air entertaining admixturesPlastic Shrinkage CrackingPlastic shrinkage cracking occurs in the concrete when there is an excessive and rapid loss of water from concrete before it has even set. This occurs when the rate of evaporation of surface moisture is higher than the rate of bleeding of water in concrete. This problem is very common during hot weather conditions.Here are the ways to avoid plastic shrinkage cracks in concrete:1.Avoiding overmixing of the concrete.2.Providing sunshades around the concrete in hot weather.3.Placing or constructing temporary walls to block or reduce wind velocity.4.Placing concrete either early in the morning or in the late afternoon to avoid hot temperaturesDustingDusting refers to the formation of a loose powdery layer on the surface of the concrete. Dusting is often found on traffic exposed concrete surfaces.How to Stop Concrete Dusting:1.Maintaining perfect water-cement ratio.2.Using dust-free aggregates.3.Giving the concrete proper time to cure or dry.4.Using sealers to make concrete dusting proof.SegregationSegregation, in a nutshell, is the process of separating the cement paste from the particles in the concrete. The cement paste rises to the top of the concrete, while the aggregates sink to the bottom. Good concrete is an even and homogenous mixture, therefore segregation impacts its durability and strength.Ways to prevent segregation:Using the correct amount of water and cement.Over-vibration of the concrete or compaction should be avoided.Its important to be careful when handling and transporting concrete.The use of concrete mixing standards, such as speeding up the process.To prevent concrete from falling from great heights.CurlingConcrete curling occurs when there is a difference in both temperature and moisture of the top and bottom surface. When curling occurs, the slab of the surface becomes unsupported from the base.How to avoid concrete curling:1.Use proper curling techniques2.Place concrete joints accordingly3.Use low water content or use water reducing admixtures4.Use the largest possible aggregate size5.Ensure proper bonding when applying thin topping mixes6.Use enough, not excessive, amount of steel reinforcement in the slab7.Place concrete on a damp but absorptive sub-grade so that all the bleed water is not forced to the top of the slab

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