Concrete Mix Design:
Based on the above data and the requirements that are to be achieved for the construction of the dam are analyzed. Self compacting concrete has been used mostly in the design of major parts of the dam.For the first time China used new type of admixture known as Glenium type PCE admixture (PCE-3) for the mix used in constructing the power house.The SCC mixture contains large content of limestone powder to increase fluidity,cohesiveness and limit heat generation.These materials are less reactive and reduces the problem of fluidity loss of concrete.Three types of mixes have been used they are....
Grade of cement used is M60 as the structure needs to sustain heavy loads.
Material Mix 1 (kg/m3) Mix 2 (kg/m3) Mix 3 (kg/m3)
Cement 300 300 300
Limestone powder 248 248 248
Fine Aggregate 954 954 954
Coarse Agg (20mm) 700 700 700
Free Water 170 173 176
SP (% of CM) 4.7 (.85%) 9.3 (1.7%) 14 (2.55%)
W/C .57 .58 .59
W/P .31 .32 .32
The slump flow of mix1 is 550 mm and for mix2 and mix3 it is greater than mix 1 whose slump values are 745 and 755 mm.The blocking ratio L-box (1,10) test of mix1 was 0.81 and of mix2 and mix 3 was 1.0.The higher blocking ratio means good deformability without blockage on closely spaced obstacles and it is capable of highly flow able concrete to self compacting.
My structure has to bear a lot of heavy loads which vary seasonally through out the year and construction period is long.My structure has to remain stable for so many years as
It involves high money transactions it effects the economy and we can built it repeatedly as it takes lot of time for the construction.Based on the factors of strength and durability and high cost involving project it can be sustainable by constru...
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Disadvantages:
It is more prone to shrinkage problems and we have to add additional admixtures to complement this which is not economically feasible
Fly Ash:
Source:
Fly ash generally obtained near the thermal power plants as a residue from combustion of powdered coal.
Advantages:
Fly ash helps in increasing fineness which in turn increases the pozzolanic activity an we get higher strength.Fly ash mixes will have greater cohesion and improved plasticity resulting in greater workability.Increases time of setting.Bleeding decreases due to more of fines and lower water content for same degree of workability.Resistance to chemical attack and free thaw and decrease in permeability.Balling problem is reduced and superior finish is obtained.
Disadavantages:
Longer setting time,slower strength gain,Air content control,seasonal limitations and color variability.
Gunel, M. Halis. Ilgin H. Emre. "A proposal for the classification of structural systems of tall buildings" Building
Coal Combustion Residue, or coal sludge, is the byproduct of burning coal in order to make energy. It is a combination of fly ash, bottom ash, coal slag, and flue gas. According to the watchdog group “sourcewatch.org” the ...
However, the product has one significant weakness as it exhibits creep and or cold flow characteristics, under compressive loads, thus affecting the gasket’s performance, since frequent retightening is required. The point is most users of PTFE are unaware of the fact that several different materials can be used successfully for the same application. The question to ask is what product is right for your application.
Issues of defective construction or failure of building had been occur since all time ago. Each of the cases of defective construction has their own reason and most of the reason is related to its building. The main causes of the structural failure are not come from the loading but it determine by the defective design of the building. Other than that, the inferior construction material also may be the reason since the loads are being calculated based on the material specification. Usually the failure which comes from material is due to the changes material that difference from the exactly material that should be used in the construction.
In the competition known as Science Olympiad, there is an event build called “Boomilevers.” This event is comprised of building a structure to be attached on one side to a wall and bear the maximum weight possible on the other side, while the structure itself weighs as little as possible. The Boomilever is a long standing Olympiad Event and requires acute attention to detail and a critical mind in architecture in order to achieve the maximum efficiency score possible. There are many limitations and guidelines set forth in the Olympiad rules, defining how tall and long the boomilever must be and how the boomilever must attach to the wall. This leads to construction much like a real life situation, where resources must be utilized efficiently.
What kind of weather conditions will the design be under, how much force, safety, and other factors are
The dam could not be poured in a single pour due to its size, so the engineers had to think of a different method. They decided to pour the concrete in five foot high forms of varying widths, which were stacked together. Each form had multiple 1 inch steel pipes in it, totaling to 582 miles of pipe. These pipes had cool water pumped through them to speed up the curing process. The base of the dam alone needed 230 individual blocks of concrete. The blocks were stacked with alternating schemes to add to the strength. Once the block of concrete was poured and cured, the pipes were filled with grout to add extra support. Grout was also poured in between the blocks of concrete.
Concrete is one of the world’s most popular construction materials. Some six billion tonnes of concrete is produced each year in the world, making it approximately one ton of concrete for every human being per year (Fardis, 2012, p.116). However, the lifecycle of concrete does not make it the most sustainable building material at the moment. Because of limited natural resources, concerns over green house gases, and landfill problems, concrete production is being cut-back, or at least cannot be increased to keep up with population increase. In this essay, I will look at what makes concrete an unsustainable material and possible solutions to make concrete a more sustainable material.
Shrinking/ swelling of the stamp: During the curing process the stamp can shrink in size leading to a slight difference in the desired dimensions of the substrate patterning.
Now a days HPC is expensive than conventional concrete. It require additional materials in some quantities as to meet specified performance.These additional materials are cement,silica fume,...
Fanella, D. (2011). Reinforced concrete structures: analysis and design / David A. Fanella. New York: McGraw-Hill, c2011.
Because Yuhu is located in an earthquake zone, the capability to resist earthquake is highly concerned for the local buildings. In tradition houses, the main structure is hold by wood frames and stones are mounted on the exterior. During the 1996 level 7 earthquake, most of the exterior stone walls were collapsed but wood frame structures well remained. In the design of this project, Li adopted this traditional structure system and added new technologies to improve its resistance to earthquake. In traditional house construction, stones are mounted to the exterior walls and are likely to collapse during earthquake. In this project, vertical steel bars are inserted in the stone walls at a set interval. Horizontal meshes are also installed in layers to prevent lateral force during frequent earthquakes. Traditional stone wall con...
The American Petroleum Institute (API) recognizes nine different Portland cement types. These different types of cements are distinguished by their different compositions allowing them to be used in different conditions. These different types of cement are presented in Table 1.2 along with their applications. In the united states the most common class used is class H because of its ability to be mixed with a variety of different additives to achieve a range of different requirements [7].
Sustainable buildings are becoming somewhat of a necessity in the world today. As the demand for green building develops, so does the demand for green building materials. Just as the old techniques and building materials seem to disappear in the assembly of things, they are now making a come back. Green building focuses on the efficiency of major resources like water and energy. As the cost for sustainable materials and products are on the decline, building green seems to be the most cost effective kind of design and construction. Looking specifically at green materials and their impact on the production of structures, it is evident that they are a prime choice for building material. The use of green materials should be promoted because they are better for the environment, more healthful for the consumer, and better for the economy.
Minerals can be found in every part of the earth’s crust, but with two important needs; the concentration of mineral and the size of the deposit. We want to make sure the mineral is high grade and large enough to repay the investment and make profit. Of the many mineral found, there is only a few mineral will appear to have good potential. So it must be tested widely, which costs a lot of time and speed is one of the critical factors. If the construction is financed by loans, it leads up to high interest costs.