2—factors influencing chemical attack on concrete

... Corrosion of reinforcement Alkali-aggregate reaction Chemical attack Sulfate attack (chemical attack involving sulfates) Ingress of aggressive chemicals into permeable concrete Permeable concrete ... in concrete production Their concentration in concrete has to be limited to assure corrosion resistance of reinforcement Excessive presence of chlorides may influence the composition of the concrete ... hydration, and controls the migration through the concrete of chemical species responsible for concrete deterioration; and © 2002 Jan Skalny, Jacques Marchand and Ivan Odler • pore solution, the medium...

Ngày tải lên: 08/08/2014, 10:23

... and S Mindess Concrete in the Marine Environment P.K Mehta Concrete in Hot Environments I Soroka Durability of Concrete in Cold Environments M Pigeon and R Pleau High Performance Concrete P.-C ... Bacteriogenic corrosion of concrete in waste water networks 4.13 Conditions affecting sulfate attack References Consequences of sulfate attack on concrete 5.1 5.2 Introduction External appearance ... external sulfate attack 5.3 Consequences of sulfate attack on the microstructure of concrete 5.4 Consequences of sulfate attack on the mechanical properties of concrete 5.5 Concluding remarks...

Ngày tải lên: 08/08/2014, 10:23

... sodium-sulfate attack Depending on the nature of the concrete components, the concrete processing conditions, the local macro- and micro-environments, and the form, concentration, and nature ... acid attack on concrete in the ground, British Research Establishment, Garston, Watford, UK Hobbs, D.W (1998) Minimum Requirements for Durable Concrete: Carbonation- and Chloride-induced Corrosion, ... critical issues for the future”, Concrete International 19(7): 27–33 Mehta, P.K (2000) “Sulfate attack on concrete: separating the myth from reality”, Concrete International 22(8): 57–61 Neville, A...

Ngày tải lên: 08/08/2014, 10:23

... Corrosion in Concrete, E & FN Spon, London Bloomfield, J.P (1996) Corrosion of Steel in Concrete: Understanding, Investigation and Repair, E & FN Spon, London CEN (1998) CEN/TC 104/SC N 308, “Common ... sulfate concentrations, and it is not only the concentration of sulfate anions per se but also the type and concentration of the accompanying cations that should be taken into consideration 3.4.2 ... concrete surface © 2002 Jan Skalny, Jacques Marchand and Ivan Odler Abrasion is characterized by wear of concrete surface by repeated friction caused, for example, by continuous driving on concrete...

Ngày tải lên: 08/08/2014, 10:23

... cement concrete in prairies soils of high sulphate content”, in E.G Swenson (ed.) Performance of Concrete- Resistance of Concrete to Sulphate and Other Environmental Conditions: A Symposium in Honour ... resistance of concrete , in E.G Swenson (ed.) Performance of Concrete- Resistance of Concrete to Sulphate and Other Environmental Conditions: A Symposium in Honour of Thobergur Thorvaldson, University ... disintegration of concrete containing sulphate-contaminated aggregates”, Magazine of Concrete Research 28: 130–142 Schneider, U and Piasta, W.G (1991) “The behaviour of concrete under Na2SO4 solution attack...

Ngày tải lên: 08/08/2014, 11:20

... available for reaction with cement components of the concrete mixture Quality Control is clearly one key issue in the protection of concrete against composition-induced internal sulfate attack It is ... selection of concrete quality needed in the given environment Therefore, these environmental/atmospheric conditions should be taken into consideration right at the design stage, to assure proper concrete ... concrete should be designed to give dense, low-porosity concrete matrix that can resist penetration of aggressive chemical species into hardened concrete Depending on the sulfate concentration...

Ngày tải lên: 08/08/2014, 11:20

... effect of sulfate attack on service life of concrete The model is based on following assumptions: Sulfate ions from the environment penetrate the concrete by diffusion; Sulfate ions react expansively ... expansion upon sulfate attack The model is based on the potential for expansion provided by both C3A content of the cement and the sulfate ion concentration of penetrating aqueous solutions It ... expansion predicted by the two equations tend to differ according to the C3A content of the cement used in the preparation of the concrete mixture Equation (7.7) (valid for a wide range of concrete...

Ngày tải lên: 08/08/2014, 11:20

... Minimize Attack on Concrete by Sulfate Soils and Waters Crammond, N.J., Longworth, T.I and Sibbick, R.G (2001) “Tredington–Ashchurch Bridge on the M5: Examination of TSA-affected concrete foundations ... Concrete deterioration from physical attack by salts”, Concrete International, January, pp 63–68 Heinz, D and Ludwig, U (1987) “Mechanism of secondary ettringite formation in mortars and concretes ... Conditions, A Symposium in Honour of Thorbergur Thorvaldson, University of Toronto Press, 13 contributions, 243 pp Taylor, H.F.W (1994) “Sulfate reactions in concrete – microstructural and chemical...

Ngày tải lên: 08/08/2014, 11:20

... Durable Concrete, ACI Manual of Concrete Practice: Part – 1998, American Concrete Institute, Farmington Hill, MI ACI 318-99 (1999) Building Code Requirements for Structural Concrete, American Concrete ... degradation 9.2 PRESCRIPTIVE STANDARDS FOR CONCRETE TO BE EXPOSED TO SULFATE ATTACK As the resistance of concrete to sulfate attack depends not only on the cement employed but also on the mixture ... cycles: This form of storage simulates conditions of cyclic migration of sulfate-containing water into concrete It results in concentration of the sulfate near the concrete surface and leads to an enhancement...

Ngày tải lên: 08/08/2014, 11:20

Ngày tải lên: 08/08/2014, 11:20

... data collection method Interpretation of data Result & discussion Implications and limitations Literature review Literature review Customer satisfaction   Customer satisfaction construct indicates ... satisfaction on consumer behavioral intentions in service environments Journal of Retailing, 76(2), 193– 218  Cronin, J J., & Taylor, S A (1992) Measuring service quality: A reexamination and extension ... and Consumer Services, 16, 352 –359  Gustafsson, A., Johnson, M.D., Roos, I.(2005) The effects of customer satisfaction, relationship commitment dimensions, and triggers on customer retention...

Ngày tải lên: 18/04/2014, 16:24

... Purchase intentions are personal action tendencies relative to the brand Whereas attitudes are summary evaluations, intentions represent “the person’s motivation in the sense of his or her conscious ... exploitation, reproduction, editing, distribution, as well as in the event of applications for industrial property rights LITERATURE REVIEW (con’t) Customer satisfaction • Customer satisfaction can ... customer satisfaction? oDoes Customer satisfaction relation to purchase intention? â All rights reserved, also regarding any disposal, exploitation, reproduction, editing, distribution, as well as...

Ngày tải lên: 18/04/2014, 16:28

... child and parent reports has been the Pearson product-moment correlation coefficient [16] However Pearson r values provide information on the covariation among scores but not indicate absolute agreement ... 23 items that contribute to a Total Score and four subscales: physical functioning, emotional functioning, social functioning and school functioning It has been shown that scores on the subscale ... similar conclusions, with younger age predicting greater differences between parents and children with epilepsy An additional factor for consideration here is the impact of parents' own functioning...

Ngày tải lên: 20/06/2014, 15:20

... organizational attraction Past research on the effects of RJPs on organizational attraction has not included employed persons; however, these findings suggest that future research may consider ... and whether the information given was an honest description of working in a school Participants responded on a 5-point continuum ranging from = strongly disagree to = strongly agree Work Experience ... organizational attraction The following discussion is presented in three sections First, the findings of the research are discussed Second, implications of findings are considered Finally, limitations...

Ngày tải lên: 07/07/2014, 10:38

... PSYCHOLOGICAL CONTRACT  Economic exchange  Social exchange AFFECTRELATED  Attribution  Rationalization  Met expectation  Person-job fit  Need satisfaction NORM-RELATED  Expectations  Obligations ... COMMITMENT  Organization  Union  Team CONTINUANCE COMMITMENT  Organization  Union  Team NORMATIVE COMMITMENT  Organization  Union  Team  Withdrawal cognition  Turnover intention  Turnover ... relations Nature of job Salary and compensation on performance Job satisfaction Performance management and promotion Training and development Role ambiguity Role conflict Secondary working conditions...

Ngày tải lên: 29/06/2015, 09:52

... (Ionescu and Caira, 2005a; Khojasteh et al., 2010) Major Phase II conjugation reactions include glucuronidation, sulfation and acetylation (Ionescu and Caira, 2005b) Of all the Phase II reactions, ... reactions, glucuronidation, which involves conjugation of the parent aglycone to a α-Dglucuronic acid sugar moiety, is the major route of conjugation and mainly occurs in the liver (Ionescu and Caira, ... polyaromatic, one hydrogen bond donor, may contain amines or amides CYP2A6 8.6% B, N Small size, nonplanar, at least one aromatic ring CYP2B6 2.1% B, N Medium size, angular, 1–2 Hbond donors or acceptors...

Ngày tải lên: 09/09/2015, 11:27

... items loading on component 3, three items loading on component 4, four items loading on component 5, and four items loading on component 38 Table 4.4: EFA results Component Matrix a Component Dis02-Distance ... discussion on the utilization of statistical tool as one of the approaches available to 10 segregate the contribution of each variable hence enabling the quantification of perceived contribution in ... characteristic), location and life environment attributes (contain of neighborhood) impact on buying decision process During last economic recession years, there was a phenomenon of bubble real estate...

Ngày tải lên: 24/09/2015, 16:18

... for which they have to allocate a fund on monthly basis as a donation and treat this donation as a part of their fixed expense Moreover, law and order situation created due to rift between different ... varies from nations to nations The formulation of any microfinance model for a specific population involves a June 27-28, 2012 Cambridge, UK 2012 Cambridge Business & Economics Conference ISBN ... impact on decision making of the respondents The borrower’s behavior is derived from their educational, cultural, economic, political and communal facets These facets have a sound influence on behavioral...

Ngày tải lên: 06/09/2013, 05:48

... the early morning • The attack was planned by Isoroku Yamamoto • The first attack occurred at 7:55 a.m • The second attack followed at 8:54 a.m Attack Visual • The first attacks would hit the ... the Attack Japan was also attacking Great Britian Malaya Hong Kong United States Phillippine Islands Guam Midway Wake Island * Japan would control the entire Pacific by December After the Attack ... States declared war on Japan • December 11: Germany declared war on America – Italy then declared war on America – Great Britain declared war on Japan America’s Reaction • Many sons enlisted into...

Ngày tải lên: 20/01/2014, 13:20

... the configuration file into memory as follows: Switch#copy flash:config.text system:running-config Source filename [config.text]?[enter] Destination filename [running-config][enter] e The configuration ... prompt to start the Setup program: Continue with the configuration dialog? [yes/no] : N c Type rename flash:config.old flash:config.text to rename the configuration file with its original name at ... forget to type the colon (:) after the word flash e Type rename flash:config.text flash:config.old to rename the configuration file This file contains the password definition 2-7 CCNA 3: Switching...

Ngày tải lên: 24/01/2014, 19:20