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National Research University Moscow State University of Civil Engineering Scientific and educational center « Nanotechnology ». PRINCIPLE OF REALIZATION NANOTECHNOLOGY IN BUILDING MATERIALS. Author : Korolev E.V. DSc. , prof ., advisor RAASN director SEC « Nanotechnology ». 2013.
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National ResearchUniversity Moscow State University of Civil EngineeringScientific and educational center «Nanotechnology» PRINCIPLE OF REALIZATION NANOTECHNOLOGY IN BUILDING MATERIALS Author: Korolev E.V.DSc., prof., advisorRAASNdirectorSEC «Nanotechnology» 2013
Addition of synthesized nano-objects in the material • Synthesis of nano-objects into material during manufacturing Strategies of modification of building materials Primary nanomaterials
Efficiency of the addition of nanoscale objectsin various materials Normalized value of the criterion Concrete Polymer Metal DF – effect of the addition of primary nanomaterial(DFmax = 300 %) Сf – concentration of primary nanomaterial(Сmax = 0,1%)
Potential of the technologyIt Potential of the materialIm Dualism of technology and mixture Rт Rj Rmax,j
PotentialΦmtof various technological methods 2 3 4 5 6 7 8 9 10 11 1 1 – increasing of portland cement activity; 3 - decreasing of the initial water content by means of plasticizing agents; 2 - application of prepared fillers; 4 – addition of inorganic admixtures to increase the densityof structure; 6 - application of vibro-activated cement to disaggregate flocculus and to seal the cement gel; 5 – addition of polymer substances to seal the structure; 7 – intensification of seal process of hard mixtures; 9 - impregnation of the pore structure of concrete with organic matter or sulfur; 8 – processing in vacuum, centrifugation, filtration pressing; 11 - use of the water-absorbing barriers 10 - dry forming;
Models of the materials’ strength ► Rehbinder Equation whereγ – coefficient; fc – strength of contact ; N – number of connections ► Other equations describing composite materials’ strength
Influence of parameters of the pore space on the stress state where whereηп – limit fraction ofpores; νп – volumefraction ofpores
Dependence between the cement paste strength and the average pore size MPa 1 – tobermorite and similar materials ; 2 – CSH(I); 3 – С3АН6and hydrogarnet; 4 – mixture 70-80 % of hydrogarnetand 20-30 % CSH(I)
Main principle of the Implementation of nanotechnology The implementation of nanotechnology should be conducted only after exhausting the possibilities of macro- and microtechnology. The size of the mass defect in the material is a criterion to assess whether to go to the nanoscale level. Conditions for optimization of the composite by scale levels from micro to macro level - Пm – porosity, which is formed as a result of incomplete concrete sealing; - [Са(ОН)2] – concentration Са(ОН)2; - W/C – water-cementration Optimization on nanoscale level • σf – internal stresses at the interface; • χm– fracture of tobermorite and similar materials; • [C–S–H] – concentration of tobermorite and similar materials.
Bases • Forming dense low-defect structure of material in composite system is possible at lower values of the internal stresses • The decrease in internal pressure is possible by lowering the differences in physical properties of the dispersed phase and the matrix material • Decrease in internal stresses can be achieved by specific technology: by means of coating the layer of dispersed phase by precursor that physically changes during the manufacturing process
The thickness of the layer of precursor 152 151 150 15 44 73 113 112 111 11 33 54 102 101 100 10 29 49
а) without precursor б) with precursor 16 22 14 20 18 12 2 16 2 см 10 см / / 2 14 2 В В , , 8 12 АЭ АЭ Е Е 6 10 8 4 6 2 4 0 2 0 0,2 0,4 0,6 0,8 1 0 f – quartzpowder, = 180 m / kg ; S 2 отн 0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1 sp f – also , = 300 m / kg ; S 2 отн - = 1,0 %; = 3 h С t sp ап T – alos , = 420 m / kg S 2 - = 1,0 %; = 1 h С t sp ап T Kinetics of the acoustic emission
14 2150 12 2100 10 Porosity, % 8 2050 Density, kg/m3 6 2000 3 4 1950 0 2 2 1900 1 t , ч 1 T 0 1850 t , ч 2 Т 0 0 0 0,2 0,2 3 0,6 С , % 0,6 1 С , % п п 1 Density and porosity
60 16 15 55 , , 14 50 13 Compressive strength MPa 45 12 Flexural strength, MPa 40 11 35 10 0 0 9 30 0,2 0,2 8 25 3 C , % C , % ап ап 2 0,6 20 0,6 3 t , ч 1 2 T 1 1 1 t , ч 0 T 0 = + + + E 15225 6311,6 Х 515,9 Х 2027,6 Х у 1 2 3 - - - = + + - 2 2 3 l 0 , 05 1 , 4· 10 Х 1 , 2 · 10 Х 6 , 9 · 10 Х max 1 2 3 Mechanical and deformation properties а) Flexural strength б) Compressive strength Experimental and statistical models – for elastic modulus, MPa, – for flexture at maximum load, mm, Х1 – duration of isothermal exposure, h; Х2 –concentration of bonding agent, %; Х3 – volume fraction of the silica filler
National ResearchUniversity Moscow State University of Civil EngineeringScientific and educational center «Nanotechnology» Thank you for your attention! SEC «Nanotechnology» +7-499-188-04-00, info@nocnt.ru www.nocnt.ru, ноцнт.рф Moscow, Yaroslavskoe shosse 26 2013