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  • 151.
    Hellström, Björn
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Hård, Rune
    Studies on fresh concrete1976Report (Refereed)
  • 152.
    Hellström, Björn
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Jönis, Per Johan
    Lagningsmetoder1978Report (Refereed)
  • 153.
    Hjort, Bengt
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Armeringsarbete på byggarbetsplatser.: En översiktlig studie1982Report (Refereed)
  • 154.
    Hjort, Bengt
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Manufacturing accuracy in connection with bending of reinforcement1984Report (Refereed)
  • 155.
    Hjort, Bengt
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Placement of floor slab reinforcement. P. 1, Traditional methods.: Studies and comparisons1984Report (Refereed)
  • 156.
    Hjort, Bengt
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Placement of floor slab reinforcement. Placement of floor slab reinforcement.: Methods development1984Report (Refereed)
  • 157.
    Hjort, Bengt
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Reinforcement work on construction sites.: A general study1983Report (Refereed)
  • 158.
    Hjort, Bengt
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Petersons, Nils
    The need for concrete research in production technology and rebuilding: program study1979Report (Refereed)
  • 159.
    Holmgren, Jonas
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Alemo, Jan
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Skarendahl, Åke
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Stålfiberbetong för bergförstärkning.: Provning och värdering.1997Report (Refereed)
    Abstract [sv]

    The report describes how quality of material and execution can be evaluated for rock strengthening carried out in steel fibre sprayed concrete. Sampling in fresh concrete as well as shooting of test slabs for determination of properties in the hardened stage is described. Test methods for fibre content in fresh and hardened concrete are given. For hardened concrete, emphasis is given test methods for flexural properties and bond, but compressive strength is also treated. Durability questions are discussed and in addition, determination of shrinkage, density as well as thickness is given. Proposals for acting in the case of not accepted test results are given.

  • 160.
    Hård, Rune
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Betongs gjutbarhet: en provningsmetod1975Report (Refereed)
  • 161.
    Hård, Rune
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Jönis, Per Johan
    Erfarenheter från besiktningar av godkända betongfabriker, 19741974Report (Refereed)
  • 162.
    Hård, Rune
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Klevbo, Göran
    Erfarenheter från besiktning av godkända betongfabriker1980Report (Refereed)
  • 163.
    Höbeda, Peet
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Johansson, Lars
    Kvalitetskriterier för grus- och makadammaterial: en litteraturinventering1975Report (Refereed)
  • 164.
    Janz, Mårten
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Kloridtransport in i pågjutning.: Resultatredovisning av pilotstudie2005Report (Refereed)
  • 165.
    Janz, Mårten
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Properties of foamed concrete manufactured with polyaluminium2005Report (Refereed)
  • 166.
    Johansson, Arne
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Flytbetong1979Report (Refereed)
  • 167.
    Johansson, Arne
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Flytbetong.: Egenskaper, arbetsteknik och användningsmöjligheter1979Report (Refereed)
  • 168.
    Johansson, Arne
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Fältprovning av metod för uppskattning av hållfasthetsökning vid vakuumbehandling av betong1976Report (Refereed)
  • 169.
    Johansson, Arne
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Sammansättning av högvärdig betong lämplig för vakuumbehandling1981Report (Refereed)
  • 170.
    Johansson, Arne
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    The relationship between mixing time and type of concrete mixer1971Report (Refereed)
  • 171.
    Johansson, Arne
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Norberg, Jan
    Färsk betongs reologi.: Mätningar på fabriksbetong1994Report (Refereed)
  • 172.
    Johansson, Arne
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Norberg, Jan
    Färsk betongs reologi.: Teori och mätmetodik1994Report (Refereed)
  • 173.
    Johansson, Arne
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Petersons, Nils
    Flytbetong.: Egenskaper, användning, erfarenheter1982Report (Refereed)
  • 174.
    Johansson, Arne
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Tuutti, Kyösti
    Pumpbetong och betongpumpning1976Report (Refereed)
  • 175.
    Johansson, Arne
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Tuutti, Kyösti
    Pumpbetong och betongpumpning.: Betongmassas strömning i rör1976Report (Refereed)
  • 176.
    Johansson, Arne
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Warris, Birger
    Deviations in the location of reinforcement1969Report (Refereed)
  • 177.
    Johansson, Arne
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Åberg, Lars
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Undergjutningar1981Report (Other academic)
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  • 178.
    Johansson, Lars
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Betongbalkonger.: Tillstånd, besiktning och reparation1980Report (Refereed)
  • 179.
    Johansson, Lars
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Bovänliga balkongreparationer: En litteraturstudie1991Report (Refereed)
    Abstract [sv]

    Den stora mängd balkonger som hittills reparerats tillhör huvudsakligen det något äldre beståndet. Reparationerna har i regel inneburit mycket stora ingrepp i konstruktionen. Reparations- och underhållsarbeten börjar nu bli_x000D_ aktuella även för många yngre byggnader. Samma förfarande som använts tidigare leder för de senare i många fall till oacceptabla konsekvenser i form av obehag för de boende och höga kostnader._x000D_ Mot denna bakgrund har en kartläggning genomförts för att belysa i vad mån_x000D_ nya metoder och material erbjuder möjligheter till enklare och bovänligare balkongreparationer._x000D_ Studerade nya metoder och material synes erbjuda både bo- och utförandevänligare_x000D_ alternativ. Man saknar dock f n kunskap om sådana reparationers beständighet och det är därför svårt att bedöma den totala kostnadsbilden.

  • 180.
    Johansson, Lars
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Flame cleaning of concrete: a study of the effects of flame cleaning on concrete1977Report (Refereed)
  • 181.
    Johansson, Lars
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Flamrensning av betong1975Report (Refereed)
  • 182.
    Johansson, Lars
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Rekommendationer för genomfärgad platsgjuten betong1996Report (Refereed)
  • 183.
    Johansson, Lars
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Reparation av betongbalkonger1991Report (Refereed)
  • 184.
    Johansson, Lars
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Skador hos betongbalkonger1976Report (Refereed)
  • 185.
    Johansson, Lars
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Ytbehandling av betongkonstruktioner utomhus1993Report (Refereed)
  • 186.
    Johansson, Lars
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Ytskydd för betong.: En litteraturstudie1992Report (Refereed)
  • 187.
    Johansson, Lars
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Klevbo, Göran
    Concrete with crushed aggregate1981Report (Refereed)
  • 188.
    Johansson, Lars
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Sundbom, Sven
    Permeabilitet.: Provning och inverkan på betongs beständighet1989Report (Refereed)
  • 189.
    Jonasson, Jan-Erik
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Datorprogram för icke-linjära beräkningar i betong med hänsyn till svinn, krypning och temperatur1977Report (Refereed)
  • 190.
    Jonasson, Jan-Erik
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Slipform construction.: Calculations for assessing protection against early freezing1985Report (Refereed)
  • 191.
    Jönis, Per Johan
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Håltagning i och partiell rivning av betong vid ombyggnader.: Teknik, ekonomi, arbetsmiljö och metodvalskriterier1985Report (Refereed)
  • 192.
    Kasperkiewicz, Janusz
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Skarendahl, Åke
    Bibliography on fibre reinforced and polymer impregnated cement based composites1974Report (Refereed)
  • 193.
    Kasperkiewicz, Janusz
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Skarendahl, Åke
    Toughness estimation in FRC composites1990Report (Refereed)
  • 194.
    Kjellsen, Knut O
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Fjällberg, Leif
    Quantitative analysis of the major phases in sulfate-resistant cement silica fume systems by SEM, 29Si NMR and XRD methods1997Report (Refereed)
    Abstract [en]

    Pastes based on a sulfate-resistant cement, with or without silica fume, and of water/binder ratios in the range 0.25 to 0.55 have been studied. Thus, the binder phase of high-performance concrete as well as of ordinary concrete is covered. The phase composition of the unhydrated cement, and the degree of hydration of the major cement phases from 1 day to 9 months have been determined in a multi-method effort. The non-evaporable water content of the pastes and the pozzolanic activity of the silica fume are also reported. The obtained phase composition of the cement depends somewhat on which method is used for its determination. The Bogue method seems to overestimate the content of ferrite. Silica fume does not appear to influence the cement hydration, except for pastes of very low water/binder ratios where the presence of silica fume reduces the cement hydration somewhat at later ages. The various direct methods (SEM image analysis, 29Si NMR and QXDA) mostly provide similar results of the degree of hydration. In high-performance concrete as much as 50% of the original cement may remain unreacted. The degree of hydration is not well estimated by the non-evaporable water content by use of a commonly applied formula relating the non-evaporable water content to the degree of hydration. Improved coefficients are provided.

  • 195.
    Kjellsen, Knut O
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Lagerblad, Björn
    The influence of natural minerals in the filler fraction on the hydration and properties of cement-filler mortars1995Report (Refereed)
    Abstract [en]

    Natural mineral fillers generally comprise a significant part of the constituency of cement- based materials. An increased understanding of the interaction between cement and natural mineral fillers is thus considered important. The effect of mineralogy of fillers on the hydration behavior and certain properties of cement-filler mortars has been studied in the present work. The minerals studied were calcite, quartz, orthoclase, albite, anorthite and wollastonite. The results showed that the presence of these minerals generally accelerated the early cement hydration. Calcite and wollastonite tended to reduce the length of the induction period and calcite appeared to increase the hydration rate during the acceleratory period. Anorthite increased the third major heat peak. The other minerals influenced the hydration behavior to a much lesser degree. Possible mechanisms leading to the different hydration kinetics are discussed. The workability of the mortars appeared to be positively influenced by the presence of calcite, wollastonite and anorthite. The presence of the other minerals had little effect on the workability. Wollastonite possess tensile strength enhancement properties for cement-based materials.

  • 196.
    Klingstedt, Gunnar
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Fjällberg, Leif
    Cement hydration and microstructure at elevated temperatures: A literature study1992Report (Refereed)
  • 197.
    Lagerblad, Björn
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Carbon dioxide uptake during concrete life cycle.: State of the art2007Report (Refereed)
    Abstract [en]

    Carbonation results when carbonate ions from dissolved carbon dioxide react with the Ca ions of the cement paste and precipitate calcium carbonate. By time all Ca-bearing cement hydrates will decompose and form calcite. The end product will apart from calcite be silica gels, metal hydroxides and clays. Carbon dioxide and water can be found in almost every environment and thus all concretes will be subjected to carbonation. The cement paste will in the course of time go back to the basic components in cement production. Therefore, the question is not if concrete and other cementitious products will carbonate, but how fast they will carbonate. In geological terms the cement paste turns into marly limestone and the concrete into marly agglomerate. Old Roman concrete structures are basically such a rock. _x000D_ _x000D_ Carbonation is a process from the surface, i.e. the amount of carbonated material is related to exposure time and surface. Surfaces in direct contact with carbon dioxide and water will carbonate rapidly but a shell of already carbonated concrete will slow down the carbonation of the interior. Thus to be able to calculate the CO2-uptake we must know the transport mechanism of carbon dioxide and carbonate ions through the already altered product. The process of passing a shell of already carbonated concrete is complex. The speed of carbonation is apart from the amount of CO2 in the environment also governed by the size and geometry of the porosity, the degree of water saturation, the type of cement/binder, the temperature, etc. Even concrete submerged in water or buried in soil will carbonate but at a slow speed due to biological degradation and the slowness of exchange reactions between water and the gases in the atmosphere. _x000D_ _x000D_ To be able to calculate CO2 uptake one must consider the microclimate at individual concrete surfaces, concrete qualities and cement/binder types in a time frame. Thus approximations are needed. In the general case assuming a similar environment and concrete quality the carbonation rate slows down with the square root of time. By choosing the most common types of concrete structures, estimating the exposed surfaces in different environments and concrete qualities it is possible to get a good estimate of the rate of carbon dioxide uptake. _x000D_ _x000D_ As a consequence of the rapidly decreasing rate of carbonation one can assume that most of the carbonation of concrete structures takes place during the first 50 years and after demolition as this will increase the surfaces dramatically. One must, however, also consider that the types of cement and quality of the concrete have changed and will change over time. Thus there will be a difference between how much is taken up today and how much that will be taken up in 50 years from now. Concrete is a fairly modern material and most concrete structures still remain but we can expect the amount of demolished concrete to increase in the future. A guess is that a 100-year perspective most concrete structures that exist today will probably be demolished and most of the carbonate rock calcinated during cement production will be back as a carbonate rock. _x000D_ _x000D_ To be able to calculate the carbonation rate some simplifications are needed. In this report concrete strength is used as a substitute for porosity and from literature data constants for different environmental classes are selected. The influence of different cements and additions is handled by correction factors. _x000D_

  • 198.
    Lagerblad, Björn
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Trägårdh, Jan
    Alkalisilika reaktioner i svensk betong1992Report (Refereed)
  • 199.
    Lagerblad, Björn
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Trägårdh, Jan
    Ballast för betong.: Egenskaper, karaktärisering, beständighet och provningsmetoder1995Report (Refereed)
    Abstract [sv]

    This report is a summary of the present level of knowledge with regard to aggregates in concrete. It focuses on the composition of aggregates and the mineral and petrographical variations which affect the quality and properties of the aggregates. _x000D_ _x000D_ The report starts with a brief description of how aggregates reacts in fresh, new and hardened concrete. This information provides the basis for understanding why it is important to require a certain quality from aggregates in concrete. After that there is a chapter about the different types of rocks and their composition. The description is a brief summary of the geological know-how required to understand the variations of aggregates and the underlying reasons for many of the positive and negative properties of concrete. _x000D_ _x000D_ The second half of the report, from chapter 5 onwards, mainly deals with how to examine and describe aggregates. The description is based on the standards which are being drawn up in Europe, the so-called CEN-standards. As soon as they are ready, they will be used as Swedish standards. The regulations covering aggregates in concrete, which are based on international experience, are more comprehensive and slightly more detailed than those we have been used to in Sweden. _x000D_ _x000D_ Finally, the report contains a list of all the test methods which can be used to identify components in aggregates which can be deleterious to concrete.

  • 200.
    Lagerblad, Björn
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, CBI - Cement- och betonginstitutet.
    Trägårdh, Jan
    Conceptual model for concrete long time degradation in a deep nuclear waste repository1996Report (Refereed)
    Abstract [en]

    Cement-based materials are fundamentally unstable in a long time perspective. With time the concrete will change properties both as a consequence of recrystallisation and chemical interaction with the environment.The hydration products are stabilized by the high pH within the concrete. Thus, when the cement paste has equilibrated with the environment new phases will form. Not only reactions inside the cement paste are of interest in this context. It is also important to consider reactions with the aggregate phase and in particular reactions with the silica component in the aggregate phase due to the high pH from alkali hydroxides and subsequent reactions of the alkali silica hydrate phases. This has been a special subject of research at CBI. The rate of the chemical reactions in concrete in general is governed by a combination of dissolution mechanisms, diffusion and permeability/porosity. The main controlling factor is the dissolution of calcium hydroxide (portlandite) which buffers and controls the pH in the cement paste. Another important factor is the permeability of the concrete. During the first period the permeability will decrease as a consequence of continued hydration and recrystallization of the cement paste. _x000D_ _x000D_ One of the main difficulties with a conceptual model for concrete degradation is the change in the geochemical environment with time.The degradation process must be treated as a sequence of different degradation mechanisms. During the first period the concrete will alter as a result of contact with atmospheric gases especially carbon dioxide which will carbonate the surface. Later the degradation will mainly be governed by the composition of the groundwater with which it will try to equilibrate. Thus the composition of both the groundwater and the concrete will change. Considering the groundwater chemical conditions at repository depths (500 m), it is possible that with time the groundwater will change composition from normal to saline. This may in fact be an advantage because the solubility of the cement paste components decreases. However, the concrete itself will influence the groundwater composition and create an aureole with increased pH around it. Most of the components in both the fresh and saline water will not be harmful to concrete. One of the problems may be the chlorine anions, as this anion may substitute for sulphate in some of the cement phases. This will not degrade the concrete but the sulphates in the cement may be released to the groundwater. The end product of the concrete, after leaching and after the pH buffer capacity has been lost, will be a mix of metastable calcium silicate hydrates, zeolite and clay minerals. _x000D_

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