recipe for self compacting concrete (scc) ?
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typically this is determined by the company making the admixtures.  If you do not have access to high range water reducers/superplasticizers then you are not going to make it happen without segregation and a w/cm ratio that will make it useless.\n\nAlso SCC is very dependent upon the gradation of the aggregates, it has much more in the way of fine aggregates than standard concrete mixes.\n\nHere's a rough example:\n780 pounds cement\n1300 pounds sand\n500 pounds 3/8" chips\n1000 pounds 3/4" nominal diameter aggregate\n36 gallons of water\n\nThe admixture dosages are going to be different depending upon the company making the chemicals.\n\nThis is rough and would end up with an overyield.  SCC is something that to be developed you need a lot of experience or a lot of test batches.  Also go to the Precast/Prestressed concrete institute website.  A while back they had a preliminary guide regardint SCC
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It depends on what superconductor do you want to make. For example, let me give you a brief idea about making the most common 'High-Tc Superconductor' YBCO:\n\nRecipe for a homemade superconductor \n1.825g or 0.005M  Y(NO3)3.5H2O \n2.614g or 0.010M  Ba(NO3)2 \n3.624g or 0.015M  Cu(NO3)2.3H2O \n\nWeigh out the ingredients and grind together thoroughly in a mortar. Transfer the mixture to an alumina crucible and place in the centre of a tube furnace. Pass a slow flow of oxygen over the mixture and bake at 350°C for 1 hour. Then increase the temperature to 950°C and cook for a further 3 to 4 hours.  \nAllow the furnace to cool somehwhat before removing the crucible with tongs and gloves. Let the crucible cool on a fire-brick before emptying the contents into the mortar. Re-grind thoroughly.  \nThen press two 13mm pellets from the mixture (at 12 tons pressure). Place them in a crucible lined with platinum foil. An unlined crucible won't do since it would contaminate the pellet. Re-heat the crucible in the furnace to 950°C with a slow flow of oxygen. Programme the furnace to cool the sample at 50°C/hour through the tetragonal-orthorhombic phase transition (at 690°C). Ensure an appropriate sign for an overnight reaction is displayed on your furnace and do remember to ask a Senior Demonstrator first! Switch off the tube furnace, allow to cool a little and then remove your sample as before. \n\nJust a note at the end: You can't say Superconductors are 'conductors' with no resistance! In fact, superconductors are materials which essentially show the following two properties:\n1. zero electrical resistance, and\n2. expulsion of magnetic field.
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I assume you mean cement and concrete.\n\nCement is the bonding agent used to make concrete mix.  In addition to cement, concrete is made of aggregate (gravel and rock) and water.  The formulas vary somewhat according to the application, and whether the concrete will be pumped when it is poured.  You should not have too much water in the concrete mixture because it will reduce the strength of the concrete when it is cured.  Many times a sample of the concrete is poured for laboratory testing at a later date.\n\nThe evaporation of water from the poured concrete must be controlled while it is curing for maximum strength.  This can be accomplished by spraying water on the surface several times a day.  The hotter the weather, the more frequently it should be wetted.  Alternatively, there are products available that make a moisture barrier to reduce evaporation when sprayed on the surface of the concrete.\n\nReinforcing steel (rebar) is used inside concrete structures to improve strength and reduce cracking.  Building codes may give guidance as to the quantity and placement of rebar, but sometimes a structural engineer should be consulted.  Wire mesh is commonly used for large flat areas, like a slab or sidewalk, but it is not very effective and rebar is preferred.\n\nCement is also used with sand and lime to prepare mortar for masonry (brick and concrete block), and for plastering and stucco.  When the mortar is to be used for ceramic tile, the sand is usually omitted.
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This is what I found:\n\nCALCIUM CHLORIDE\n\nCalcium Chloride can be used for and in the following:\n\nIce and Snow Melters. Production of Calcium Salts. Cold-weather concrete additive - Soil solidification - Tractor Tire weighting. Direct drying compound. Shoulder and base stabilization. Dustproofing and freeze-resisting ore and coal. Increases web strength of corrugating media.  Improves dye retention. An additive to oil well completion fluids. Cementing finished oil wells. Drilling mud additive and drying petroleum fractions.\n\nDust Control - Concrete Accelerator:\n\nCalcium Chloride has unique properties that make it ideal for maintaining unpaved roads and fortifying road bases for new construction. It is calcium chloride's ability to regulate moisture on road surfaces that is the key to building roads that last.\n\nCalcium Chloride keeps roads moist, day-in and day out, keeping nuisance dust down. Reduced pot-holing and rutting made possible by calcium chloride surface stabilization makes roads safer year round.\n\nStabilized calcium chloride roads can reduce aggregate loss by up to 75%. In addition, they significantly reduce the frequency and costs associated with periodic grading.\n\nUniform compaction and residual calcium chloride helps protect road bases from winter freezing and related frost heaving. Long known as an effective ice melter, calcium chloride lowers the freezing point of moisture in road bases to nearly 60 degrees below zero.\n\nCalcium Chloride protection of unpaved roads and road  bases is cumulative and long-tasting. The migration of calcium Chloride from road bases is minimal. Studies have shown that calcium chloride is still present and providing stabilization in road sub-bases nearly 30 years after initial construction.\n\nCalcium Chloride maintains workability in concrete with reduced water usage. In addition, faster setting means that manpower and labor hours can be reduced. And the number of forms required for a project can be minimized, since they can be re-used faster at the job-site.\n\nCalcium chloride is commonly used in industry as an accelerator.  Accelerated rates of strength development allow for earlier removal of forms, earlier finishing operations and availability for use.  This also allows for shorter curing and protection periods which can be advantageous, especially in cold weather conditions.  Briefly, calcium chloride reduces initial and final setting, resistance to sulfate attack and bleeding.  Tensile and flexural strength are slightly decreased.  However, compressive strength, water tightness and modulus of elasticity are increased.  Resistance to damage by freezing and thawing is improved early but may be less resistant at later ages.\n\nOne of the major problems encountered with the use of calcium chloride as an admixture is the effect that the chlorides have on reinforced concrete.  Prestressed concrete can contain no significant amount of calcium chloride.  The effect of corrosion hat the presence of chlorides may produce can be controlled if appropriate measures are taken.\n\nIce Melters\n\nCalcium Chloride Liquid: a liquid brine in its natural state and is converted into a dry material by removing the water. It quickly absorbs water from the atmosphere. When calcium chloride is converted into a liquid, it gives off heat. Calcium chloride will melt ice at temperatures of-25° F.\n\nThe growing need for corrosion-inhibited deicers has prompted manufacturers to explore their production.  One example of this is a new corrosion-inhibited grade of liquid calcium chloride designed to meet or exceed deicers standards in all respects.  In addition to providing low corrosion versus salt, it has calcium chloride's operational benefits in that it continues to melt snow and ice at 20 degrees F, the temperature at which salt becomes an inefficient deicer.\n\nThose using corrosion-inhibited calcium chloride for deicing and anti-icing, report that it aggressively melts snow an
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You may want to try the American Society of Civil Engineers (ASCE), at www.asce.org. This should lead you to a place where you can get at minimum the American codes. The most widely used code in the US is ASCE 7, which is referenced in most building codes, both adopted and models. You can get a copy of ASCE 7 from ASCE's online bookstore.\n\nUnfortunately, I don't know of a place where you can get them for free, although if you are a student you may be able to get them at a reduced rate.
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hope this helps you out. molding clay is what i would use.
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If the soils removed from the excavation aren't too wet then use the same soils. \n Why do you have post tension cables on a slab on grade design?\n If you are trying to bring the subgrade level across the whole floor area to minimize the purchase of extra concrete ,then sand would prob. be the way to go.
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See if these help\n\nhttp://www.pslc.ws/macrog.htm\n\nhttp://www-classes.usc.edu/engr/ms/125/MDA125/polymers_files/frame.htm
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The Simple 16-Step Guide To Triangular Construction\n\n# 1. Obtain a crisp packet, or optionally one of the many alternatives to a crisp packet which may be utilised as the basis for this operation. These particular instructions are based on the assumption that the packet you find can be considered rectangular by somebody of sane mind. These can usually be purchased at all the most relevant shops.\n\n# 2. Relieve the packet of any extraneous contents that it may have, such as, for example, crisps.\n\n# 3. Ensure that you are now the owner of an empty and flat crisp packet (or similar item- see #1) by placing the packet in question on a floor, and stamping up and down on it for a timespan of roughly five minutes. Your stamps should be mostly in a constant vertical direction for fear of irrevocably ripping the packet, and should not greatly exceed five minutes for fear of causing it internal bleeding. This process is catalysed by the use of a hard, even an unc*rpeted, floor, and if you are a very fat person wearing heavy shoes.\n\n# 4. You are now ready to make a Crisp Packet Triangle. If you suffer from high blood pressure, it might be a little excessive to have a few medically-trained personnel on hand should you collapse during this, but such precautions will not greatly impede the Triangle making process.\n\n# 5. Find which side of the packet you are using is shorter than the other side. If this is your first time making a triangle, it might be best to use a ruler (if you are a man, be sure not to exaggerate the inches), but if you are a more experienced triangular, it may be done by visual consideration alone.\n\n# 6. Fold the packet over relative to the shorter side, so that the length of the shorter side is halved whilst the length of the more lengthy side remains the same. If you are using a crisp packet and you find that the 'spine' gets in the way of making the two sides of the fold even, do not worry. On this fold (but only on this fold) it does not matter if the two 'halves' of the fold are not equal.\n\n# 7. Repeat the process described in #6- in the same words, fold the packet over relative to the shorter side, so that the length of the shorter side is halved again whilst the length of the more lengthy side is still completely unaffected. On this fold, the lengths should meet and the halves should be equal, otherwise the triangle making procedure could be severely impinged.\n\n# 8. Remove any air that may have inadvertantly crept into the packet whilt you weren't looking. This is done by running caressing fingers along the soft packet, the soft nerves of your tender touch feeling every ripple and breath of the soft, tender skin. If you should now feel the need to go and lie down, be sure to place the packet under a heavy book before you go so that the air doesn't get back in again. On the subject of air, it is important that by this stage in the proceedings, you have not forgotten to breathe for any long period of time.\n\n# 9. If you want this easy, you could wait a month or so now until pictures are installed on this web page because describing this bit isn't easy. In effect, you should hold the packet lengthways and fold one of the ends (of the long side) through a right-angle around a diagonal pivot in the middle so that you end up with a right-angled shape. If you don't understand, get a geometry teacher to do it for you, but be sure not to listen to what they are saying with their mouths because it might prove fatal to your brain in your head. A rough illustration of this (the folding, not the geometry teachers' deadly mouths) can be seen in Fig 1.\n\nFig. 1 (above)\n\n\n# 10. Take the half of the packet that you have just folded through a right angle, and with any amount of care and precision that you choose to apply to the task, fold it underneath the triangular area just formed, so that it is now forming the other right-angle with the side that you didn't fold. Again
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you can contact me at blade_trinity_mr@yahoo.com and i will send you some PDFs about fiber reinforcement
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Right here : http://www.cement-process.com/simulator.htm\nor\ntry the TMT Kiln Simulator from http://www.udgroup.com/industries/lime_x.html
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3/4" Marine plywood: (shaped to taste hehehe!) add a little rocker....cover with marine epoxy...sand till smooth... paint.. whalla!!\nthen shuvit shuvit shuvit!!!!\n\n- good for flat water skimboarding! hikhikhik!!
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I think you need to use a special cnc machine\n any way herein below some under considration useful sites\n\n•http://www.8bestsites.com/aluminum-extrusion/6/\n\n•http://www.maytecinc.com/\n\n•http://www.extrusions.com/005issue/htmls/ExtrusionAdvantages.htm\n\n•http://unisource-tech.com/Products_-_Unisource_Technolog/Aluminum_Extrusion_front_panel/aluminum_extrusion_front_panel.html\n\n•http://www.aeroext.com/\n\n•http://www.pennaluminum.com/extproc.asp\n\n•http://www.sati.com.tw/
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Matt slabs or Mass Concrete
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here is a link to one\n\nhttp://www.snapfiles.com/reviews/CdCoverCreator/cdcovercreator.html
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http://www.processassociates.com/process/convert/cf_mtc.htm\n\nPerfect converter... hope its what you meant!
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http://www.nocfcs.org/scc/home.htm