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Johannesson, Björn
Publications (10 of 86) Show all publications
Mmari, W. & Johannesson, B. (2022). A model for multiphase moisture and heat transport below and above the saturation point of deformable and swelling wood fibers – I: Mass transport. Applications in Engineering Science, 12, Article ID 100117.
Open this publication in new window or tab >>A model for multiphase moisture and heat transport below and above the saturation point of deformable and swelling wood fibers – I: Mass transport
2022 (English)In: Applications in Engineering Science, E-ISSN 2666-4968, Vol. 12, article id 100117Article in journal (Refereed) Published
Abstract [en]

A thermodynamically consistent model for heat and mass transfer in deformable wood fibers is developed. Thehybrid mixture theory is used to model the material as a mixture of three phases, consisting of a solid, a liquidand a gas phase. The solid phase consists of dry fibers and bound water constituents, whereas the gas phasehas dry air and water vapor constituents. Emphasis is put on the mass flow and mass exchange of moisture inthe material both below and above the saturation point of the solid wood fibers. Generalized forms of Fick’s,Darcy’s and Fourier’s laws are derived, and the chemical potential is used as a driving force for mass flow.Mass exchange due to sorption and evaporation/condensation processes is implemented in the model, wherehysteretic properties both within and above the hygroscopic moisture range are described using Frandsen’shysteresis model. Moisture induced swelling/shrinkage is included where the porosity of the material canvary. A large strain setting formulated for general orthotropy is adopted for the mechanical deformations. Toshow the performance of the resulting model, it is implemented in a finite element method framework andused to simulate the processes of heat and moisture transport dynamics of a wood sample subjected to dryingfrom an over-hygroscopic moisture state.

Place, publisher, year, edition, pages
Elsevier, 2022
Keywords
Hybrid mixture theory, Sorption hysteresis, Over-hygroscopic, Swelling wood
National Category
Construction Management Wood Science
Research subject
Technology (byts ev till Engineering), Civil engineering
Identifiers
urn:nbn:se:lnu:diva-117104 (URN)10.1016/j.apples.2022.100117 (DOI)001026306800003 ()2-s2.0-85139351655 (Scopus ID)
Available from: 2022-10-25 Created: 2022-10-25 Last updated: 2023-08-10Bibliographically approved
Mmari, W. & Johannesson, B. (2022). A model for multiphase moisture and heat transport below and above the saturation point of deformable and swelling wood fibers-II: Hygro-mechanical response. Applications in Engineering Science, 12, Article ID 100118.
Open this publication in new window or tab >>A model for multiphase moisture and heat transport below and above the saturation point of deformable and swelling wood fibers-II: Hygro-mechanical response
2022 (English)In: Applications in Engineering Science, E-ISSN 2666-4968, Vol. 12, article id 100118Article in journal (Refereed) Published
Abstract [en]

A non-linear elastic constitutive model for a swelling/shrinking orthotropic wood matrix is proposed. Themodel is thermodynamically consistent, derived based on the principles of continuum mechanics and thehybrid mixture theory. Moisture induced strains are introduced considering finite deformations by assuming amultiplicative split of the deformation gradient tensor into a swelling and an elastic part. Novel definitions ofthe Cauchy stress tensor and the moisture-dependent elastic material tangent matrix are obtained. The modelis coupled to a multi-phase transient mass and heat transport model developed in Part I of this work. Inthis part of the work 2-D and 3-D test examples are used to describe the ability of the model to simulatemoisture-induced distortions when drying wood within the hygroscopic and also from the over-hygroscopicmoisture ranges. Despite deriving the model considering wood, the obtained constitutive relations can besuitably adopted to other orthotropic porous materials displaying properties similar to that of wood.

Place, publisher, year, edition, pages
Elsevier, 2022
Keywords
Moisture transport, Hygro-mechanical, Finite strains, Wood drying, Evolving orthotropy, Non-linear elastic
National Category
Wood Science Construction Management
Research subject
Technology (byts ev till Engineering), Civil engineering
Identifiers
urn:nbn:se:lnu:diva-117105 (URN)10.1016/j.apples.2022.100118 (DOI)001026306800001 ()2-s2.0-85139735663 (Scopus ID)
Available from: 2022-10-25 Created: 2022-10-25 Last updated: 2023-08-10Bibliographically approved
Mmari, W. & Johannesson, B. (2020). Modeling transient and hysteretic hygrothermal processes in wood using the hybrid mixture theory. International Journal of Heat and Mass Transfer, 163, 1-14, Article ID 120408.
Open this publication in new window or tab >>Modeling transient and hysteretic hygrothermal processes in wood using the hybrid mixture theory
2020 (English)In: International Journal of Heat and Mass Transfer, ISSN 0017-9310, E-ISSN 1879-2189, Vol. 163, p. 1-14, article id 120408Article in journal (Refereed) Published
Abstract [en]

Porous materials used in constructions and many other daily activities tend to have a strong affinity to- wards external fluids, especially moist air, which accumulates in the porous media leading to physical and mechanical effects. For wood based materials, moisture transport dynamics is a function of relative humidity, temperature and sorption history. Coupling of these three parameters has not been fully cap- tured in many of the existing numerical models, which usually make use of the classical forms of Fick’s and Fourier’s laws. A thermodynamic approach based on the hybrid mixture theory is therefore used in this work to provide a system of consistent coupled equations that incorporate multi-component pro- cesses of: Fickian-like diffusion of vapor, Darcy-like seepage of gas and Fourier-like heat transport. The sorption process is driven by the difference in chemical potential between the bound water and local vapor in the material, and governed by sorption isotherms implemented along with Frandsen’s hysteresis model. The result is a thermodynamically consistent model, which is implicitly capable of modeling in- herent hygrothermal properties including the heat of sorption. Numerical examples are implemented in a finite element method framework to describe the performance of the model in simulating moisture and heat transport dynamics in a wood section.

Place, publisher, year, edition, pages
Elsevier, 2020
Keywords
Moisture transport, Wood, Hybrid mixture theory, Sorption hysteresis, Sorption heat
National Category
Construction Management
Research subject
Technology (byts ev till Engineering), Civil engineering
Identifiers
urn:nbn:se:lnu:diva-98855 (URN)10.1016/j.ijheatmasstransfer.2020.120408 (DOI)000589421900021 ()2-s2.0-85090404857 (Scopus ID)
Available from: 2020-11-09 Created: 2020-11-09 Last updated: 2023-03-01Bibliographically approved
Addassi, M. & Johannesson, B. (2020). Reactive mass transport in concrete including for gaseous constituents using a two-phase moisture transport approach. Construction and Building Materials, 232, 1-14, Article ID 117148.
Open this publication in new window or tab >>Reactive mass transport in concrete including for gaseous constituents using a two-phase moisture transport approach
2020 (English)In: Construction and Building Materials, ISSN 0950-0618, E-ISSN 1879-0526, Vol. 232, p. 1-14, article id 117148Article in journal (Refereed) Published
Abstract [en]

This article presents the further development of a tool for multi-phase reactive mass transport modelingfor durability estimation of cement-based materials, by the addition of the gas phase, adopting a trulyseparate two-phase moisture transport approach. The governing system of equations are based on phys-ically sound hybrid mixture based version of the Poisson-Nernst-Planck system of equations includinggaseous transport in the air-filled space, ionic transport in the liquid phase, electro-migration of ionicspecies, a two-phase moisture transport model, and sorption. The addition of the gas phase and thetwo-phase moisture description enables the user of the model to investigate individual and combinedeffects of different degradation processes in unsaturated systems. The altering of hydrated cement underthree different environments were studied representing an accelerated carbonation environment, a sub-merged marine environment and a cyclic drying-wetting zone in a marine environment, to illustratesome of the model’s capabilities.

Place, publisher, year, edition, pages
Elsevier, 2020
National Category
Construction Management
Research subject
Technology (byts ev till Engineering), Civil engineering
Identifiers
urn:nbn:se:lnu:diva-92382 (URN)10.1016/j.conbuildmat.2019.117148 (DOI)000513297300051 ()2-s2.0-85073509007 (Scopus ID)
Available from: 2020-02-25 Created: 2020-02-25 Last updated: 2023-01-27Bibliographically approved
Wu, M., Fridh, K., Johannesson, B. & Geiker, M. (2018). Impact of sample crushing on porosity characterization of hardened cement pastes by low temperature calorimetry: Comparison of powder and cylinder samples. Thermochimica Acta, 665, 11-19
Open this publication in new window or tab >>Impact of sample crushing on porosity characterization of hardened cement pastes by low temperature calorimetry: Comparison of powder and cylinder samples
2018 (English)In: Thermochimica Acta, ISSN 0040-6031, E-ISSN 1872-762X, Vol. 665, p. 11-19Article in journal (Refereed) Published
Abstract [en]

Theimpact of sample crushing on the detected porosity of hardened cement pastes bylow temperature calorimetry (LTC) was studied using powder and cylindersamples. Two types of cements, CEM I and CEM III were used to prepare thepastes. A model porous material, MCM-41, was also used in order to investigatesome aspects of the measurement and the evaluation approach. The powder andcylinder samples of the cement pastes were compared in terms of the calculatedice content curves, total pore volumes and pore size distribution curves. For thetwo studied cement pastes, the calculated ice content curves of freezing of thepowder sample differed from that of the cylinder samples, especially for thepaste CEM III. The results indicate that sample crushing changed the poreconnectivity as compared to non-crushed samples. One important differencebetween the powder sample and the cylinder samples of the paste CEM III wasthat the determined maximum ice content in the powder sample was much higherthan that in the cylinder samples, the relatively difference being about 40–50%.However, this kind of marked difference was not found in the paste CEM I. Theobserved difference between the calculated pore volume of the powder and thecylinder samples of the paste CEM III is possibly due to some of the “isolated”pores which, presumably, cannot be fully filled with water in the preparationof the cylinder samples. However, sample crushing makes it possible to saturatethe pores to a greater extent if the crushing contributes to open up the“isolated” pores. Consequently, more pores are detected in the powder samples.The argument that the “isolated” pores have a tendency to be opened up by thecrushing process is supported by results using gravimetric measurements and“dynamic (water) vapor sorption” measurements on powder samples.

Place, publisher, year, edition, pages
Elsevier, 2018
National Category
Other Materials Engineering Construction Management
Research subject
Technology (byts ev till Engineering), Civil engineering
Identifiers
urn:nbn:se:lnu:diva-74363 (URN)10.1016/j.tca.2018.05.002 (DOI)000437372400002 ()2-s2.0-85047075472 (Scopus ID)
Available from: 2018-05-15 Created: 2018-05-15 Last updated: 2020-10-26Bibliographically approved
Addassi, M., Johannesson, B. & Wadsö, L. (2018). Inverse analyses of effective diffusion parameters relevant for a two-phase moisture model of cementitious materials. Cement and Concrete Research, 106, 117-129
Open this publication in new window or tab >>Inverse analyses of effective diffusion parameters relevant for a two-phase moisture model of cementitious materials
2018 (English)In: Cement and Concrete Research, ISSN 0008-8846, E-ISSN 1873-3948, Vol. 106, p. 117-129Article in journal (Refereed) Published
Abstract [en]

Here we present an inverse analyses approach to determining the two-phase moisture transport properties re-levant to concrete durability modeling. The purposed moisture transport model was based on a continuumapproach with two truly separate equations for the liquid and gas phase being connected by the sorption ki-netics. The moisture properties of ten binder-systems containingfly ash, calcined clay, burnt shale and graymicro-filler, were investigated experimentally. The experiments used were, (i) sorption test (moisturefixation),(ii) cup test in two different relative humidity intervals, (iii) drying test, and, (iv) capillary suction test. Masschange over time, as obtained from the drying test, the two different cup test intervals and the capillary suctiontest, was used to obtain the effective diffusion parameters using the proposed inverse analyses approach. Themoisture properties obtained with the proposed inverse analyses method provide a good description of the testperiod for the ten different binder-systems.

Place, publisher, year, edition, pages
Elsevier, 2018
National Category
Construction Management Other Materials Engineering
Research subject
Technology (byts ev till Engineering), Civil engineering
Identifiers
urn:nbn:se:lnu:diva-71491 (URN)10.1016/j.cemconres.2018.01.011 (DOI)000429762800012 ()2-s2.0-85041994156 (Scopus ID)
Available from: 2018-03-12 Created: 2018-03-12 Last updated: 2020-10-26Bibliographically approved
Geiker, M. R., De Weerdt, K., Garzon, S. F., Jensen, M. M., Johannesson, B. & Michel, A. (2017). Screening of Low Clinker Binders, Compressive Strength and Chloride Ingress. Nordic Concrete Research, 57(2), 23-38
Open this publication in new window or tab >>Screening of Low Clinker Binders, Compressive Strength and Chloride Ingress
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2017 (English)In: Nordic Concrete Research, ISSN 0800-6377, Vol. 57, no 2, p. 23-38Article in journal (Refereed) Published
Abstract [en]

This paper reports an initial screening of potential new binders for concrete with reduced CO2-emission. Mortars cured saturated for 90 days are compared with regard to a) compressive strength of mortars with similar water-to-binder ratio, and b) chloride ingress in similar design strength mortars exposed to seawater. The reference used was a binder composition typical for a Danish ready mixed concrete for aggressive environments and strength class C35/45. Based on the present investigation and assumptions up to around 15% reduction in CO2 emission from binder production might be obtained without compromising the 90 days compressive strength and resistance to chloride ingress in marine exposure by using selected alternative binders.

Place, publisher, year, edition, pages
Nordic Concrete Federation, 2017
Keywords
Cement, chlorides, CO2-emission, supplementary cementitious materials (SCM)
National Category
Civil Engineering
Research subject
Technology (byts ev till Engineering), Civil engineering
Identifiers
urn:nbn:se:lnu:diva-72108 (URN)000425406800004 ()
Available from: 2018-04-04 Created: 2018-04-04 Last updated: 2023-08-30Bibliographically approved
Addassi, M., Schreyer, L., Johannesson, B. & Lin, H. (2016). Pore-scale modeling of vapor transport in partially saturated capillary tube with variable area using chemical potential. Water resources research, 52(9), 7023-7035
Open this publication in new window or tab >>Pore-scale modeling of vapor transport in partially saturated capillary tube with variable area using chemical potential
2016 (English)In: Water resources research, ISSN 0043-1397, E-ISSN 1944-7973, Vol. 52, no 9, p. 7023-7035Article in journal (Refereed) Published
Abstract [en]

Here we illustrate the usefulness of using the chemical potential as the primary unknown by modeling isothermal vapor transport through a partially saturated cylindrically symmetric capillary tube of variable cross-sectional area using a single equation. There are no fitting parameters and the numerical solutions to the equation are compared with experimental results with excellent agreement. We demonstrate that isothermal vapor transport can be accurately modeled without modeling the details of the contact angle, microscale temperature fluctuations, or pressure fluctuations using a modification of the Fick-Jacobs equation. We thus conclude that for a single, axisymmetric pore, the enhancement factor depends upon relative humidity boundary conditions at the liquid bridge interfaces, distance between liquid bridges, and bridge lengths.

Place, publisher, year, edition, pages
AGU Publications, 2016
National Category
Oceanography, Hydrology and Water Resources
Research subject
Technology (byts ev till Engineering)
Identifiers
urn:nbn:se:lnu:diva-56688 (URN)10.1002/2016WR019165 (DOI)000386977900018 ()2-s2.0-84988489832 (Scopus ID)
Available from: 2016-09-23 Created: 2016-09-23 Last updated: 2018-01-10Bibliographically approved
Jensen, M. M., Johannesson, B. & Geiker, M. R. (2015). A Numerical Comparison of Ionic Multi-Species Diffusion with and without Sorption Hysteresis for Cement-Based Materials. Transport in Porous Media, 107(1), 27-47
Open this publication in new window or tab >>A Numerical Comparison of Ionic Multi-Species Diffusion with and without Sorption Hysteresis for Cement-Based Materials
2015 (English)In: Transport in Porous Media, ISSN 0169-3913, E-ISSN 1573-1634, Vol. 107, no 1, p. 27-47Article in journal (Refereed) Published
Abstract [en]

A finite element solution for a mass transport model for porous materials accounting for sorption hysteresis is presented in this paper. The model is prepared for modeling of concrete durability, but the general presentation makes it suitable for other porous materials like soil and tissues. The model is an extended version of the Poisson–Nernst–Planck (PNP) system of equations. The PNP extension includes a two-phase vapor and liquid model coupled by a sorption hysteresis function and a chemical equilibrium term. The strong and weak solutions for the equation system are shown, and a finite element formulation is established by Galerkin’s method. A single-parameter implicit time integration scheme is used for solving the transient response, and the out-of-balance solution is minimized by using a modified Newton–Raphson scheme in which the tangential stiffness is not computed exactly. The sorption hysteresis is added to the solution procedure by a rate function. The hysteresis effect is described by scanning curves defined between two boundary sorption isotherms. A numerical example was constructed to show the applicability and compare a simple approach and a extended approach within the sorption hysteresis model. The examples illustrate the impact of changing relative humidity at the mass transport boundary on the adsorption and desorption stages of a cement-based material. Changes in the pore solution ion concentrations are a result of the changing moisture content, which are shown by the example. Comparing the two approaches showed significant deviations in the liquid content and ion concentrations, in parts of the domain considered.

Keywords
Mass transport, Sorption hysteresis, Finite element method, Cement-based materials
National Category
Construction Management
Research subject
Technology (byts ev till Engineering), Civil engineering
Identifiers
urn:nbn:se:lnu:diva-48686 (URN)10.1007/s11242-014-0423-3 (DOI)
Available from: 2016-01-12 Created: 2016-01-12 Last updated: 2017-11-30Bibliographically approved
Latini, C., Zania, V. & Johannesson, B. (2015). Dynamic stiffness and damping of foundations for jacket structures. In: The proceedings of the 6th International conference on earthquake geotechnical engineering: . Paper presented at 6th International Conference on Earthquake Geotechnical Engineering 1-4 November 2015 Christchurch New Zealand.
Open this publication in new window or tab >>Dynamic stiffness and damping of foundations for jacket structures
2015 (English)In: The proceedings of the 6th International conference on earthquake geotechnical engineering, 2015Conference paper, Published paper (Refereed)
Abstract [en]

Foundation for offshore jacket structures may comprise of long floating piles. The dynamic response of floating piles to horizontal load is herein investigated. The analytical solution of horizontally vibrating end bearing piles by Novak & Nogami (1977) has been modified. At first the soil resistance as defined by Nogami & Novak (1977) is determined, considering 3D wave propagation within linear soil layer with hysteretic damping. Thereafter, the dynamic response of the pile is estimated assuming soil pressure equal to the soil resistance and imposing displacement compatibility. A parametric study clarifies the role of the parameters involved i.e. the depth of the soil layer, the pile diameter and the soil layer shear wave velocity. Results are presented in terms of dimensionless graphs which highlight the frequency dependency of the dynamic stiffness and damping.

National Category
Construction Management
Research subject
Technology (byts ev till Engineering), Civil engineering
Identifiers
urn:nbn:se:lnu:diva-48687 (URN)
Conference
6th International Conference on Earthquake Geotechnical Engineering 1-4 November 2015 Christchurch New Zealand
Available from: 2016-01-12 Created: 2016-01-12 Last updated: 2016-01-18Bibliographically approved
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