Lehrbuch der Bauphysik

Häupl, Peter; Höfker, Gerrit; Homann, Martin; Kölzow, Christian; Maas, Anton; Nocke, Christian; Riese, Olaf; Willems, Wolfgang M.

doi:10.1007/978-3-658-16074-6

Cited by 8 publications

(5 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…As for the treatment NC-27CP, a consolidant with explicitly hydrophobic components, its lasting water repellence could be proved by the low WAC values even after 6 months of curing. The WAC values can be classified as water repellent and water hindering [83] (p. 215). The slight differences in the 6 months WAC of this product between both lithotypes is also confirmed by the contact angles of water—96.78° for Schlaitdorf Sandstone and 87.26° for St. Margarethen Limestone .…”

Section: Resultsmentioning

confidence: 99%

Efficiency and Compatibility of Selected Alkoxysilanes on Porous Carbonate and Silicate Stones

et al. 2019

View full text Add to dashboard Cite

This study compares the consolidation efficiency and compatibility of three selected alkoxysilanes on two porous carbonate and silicate substrates. Emphasis was given to artificially induced microstructural defects and subsequent restoration of mechanical and physical properties. Two newly engineered formulations (1) a TiO2 modified tetraethyl-orthosilicate in isopropanol with 70% active content and (2) a TiO2 modified alkyl-trialkoxysilane in isopropanol with 75% active content were compared to a commercial product (3), a solvent free tetraethyl-orthosilicate with 99% active content. Treatments were evaluated by scanning electron microscopy, mercury intrusion porosimetry, colour impact and their effect on dynamic modulus of elasticity, splitting tensile- and flexural strengths, capillary water absorption and water vapour permeability. A key outcome was that mechanical strength gain induced by treatments is primarily governed by a stone’s texture and microstructure, and secondarily by the gel deposition rate of consolidants. Likewise, the kinetics of the gel-forming reaction during curing is dependent not only on the product but also on the substrate. Therefore, the moisture related properties and the visual impact develop during time. There is no general trend on how it evolves in time, which can lead to incorrect interpretations of treatment compatibility. The results prove that wide-ranging treatment performance is obtained when applying the same products on different substrates.

show abstract

Section: Resultsmentioning

confidence: 99%

Efficiency and Compatibility of Selected Alkoxysilanes on Porous Carbonate and Silicate Stones

et al. 2019

View full text Add to dashboard Cite

show abstract

“…One possible explanation for the extreme temperatures is the absence of latent heat fluxes and the poor thermal conductivity of the medium, so that the absorbed radiation was largely converted into heat. Such effects occur, for example, in the insulation of houses, which, due to their poor thermal conductivity, reduce the heating of the building behind them, but reach high temperatures at the radiation conversion surface [38]. Thus, a plant seed located close to the moss surface (more mobile species may retreat to cooler microhabitats) is temporarily exposed to extremely high temperatures, which could adversely affect germination.…”

Section: The Interplay Of Direct Sunlight Canopy Cover and Ground Vegetationmentioning

confidence: 99%

“…An often-described characteristic is the moderating effect of extremes, mainly temperature, wind and moisture, through forests [21,36,37]. An important driver for the temperature of the near-surface is the amount of incoming solar radiation, i.e., diffuse and beam radiation, and absorptivity of the irradiated medium, which converts the absorbed energy into latent heat fluxes (evaporation) or sensible heatfluxes (heating) [21,38,39]. Each layer of vegetation, from the tree canopy to young trees, shrubs, and herbaceous vegetation, represents an insulating layer that affects incoming radiation through processes of reflection, absorption or transmission [5,6].…”

Section: Introductionmentioning

confidence: 99%

Exploring the Thermal Microcosms at the Forest Floor—A Case Study of a Temperate Forest

Boehnke

2021

Atmosphere

View full text Add to dashboard Cite

With the expected changes in summer weather due to global warming, knowledge of the microclimatic variability at the forest floor dramatically increased in importance for silviculture, wildfire management and biodiversity issues. Thus, during the warm season in 2014, thermal aspects within a heterogeneous forest were recorded at nine sites and compared to data from a nearby weather station. It was found that soil (−5 cm) and near-surface (0–2 cm) temperatures under shaded conditions stayed remarkably cooler than temporarily or fully radiated spots inside and outside the forest; largest differences occurred in maxima (July: 22.5 °C to 53.5 °C). Solar radiation was found to be the main driver for the strong heating of near-surface microhabitats, which could be reinforced by the vegetation type (moss). The weather station widely reflected the average condition on forest floor, but lacks the biological meaningful temperature extremes. The measurement system (internal versus external sensor) resulted in differences of up to 6 K. The findings underline the importance of old or dense stands for maintaining cool microrefugia. However, also the need for careful selection and analysis of microclimatic measurements in forests, representative for specific microhabitats, under consideration of ground vegetation modifications.

show abstract

“…According to the description of the profile in WUFI Plus, data for heat emission per person was based on VDI 2078:1996 (DIN 1946-2) [36], and data for other heat sources was based on DIN V 4108-6 [37] and acquired from Nipkow et al [38]. Furthermore, data for the moisture production was according to Kunze [39] and Lutz et al [40]. Finally, data for the CO 2 production was acquired from VDI 4300-7 [41].…”

Section: Simulationsmentioning

confidence: 99%

Determining the Impact of High Residential Density on Indoor Environment, Energy Use, and Moisture Loads in Swedish Apartments-and Measures for Mitigation

et al. 2021

View full text Add to dashboard Cite

Recently, there has been an increase in apartments with a large number of inhabitants, i.e., high residential density. This is partly due to a housing shortage in general but also increased migration, particularly in suburbs of major cities. This paper specifies issues that might be caused by high residential density by investigating the technical parameters influenced in Swedish apartments that are likely to have high residential density. Interviews with 11 employees at housing companies were conducted to identify issues that might be caused by high residential density. Furthermore, simulations were conducted based on extreme conditions described in the interviews to determine the impact on the energy use, indoor environmental quality, and moisture loads. In addition, the impact of measures to mitigate the identified issues was determined. Measures such as demand-controlled ventilation, increase of a constant ventilation rate, and moisture buffering are shown to reduce the risk for thermal discomfort, mold growth, and diminished indoor air quality; while still achieving a lower energy use than in a normally occupied apartment. The results of this study can be used by authorities to formulate incentives and/or recommendations for housing owners to implement measures to ensure good indoor environmental quality for all, irrespective of residential density conditions.

show abstract

Lehrbuch der Bauphysik

Abstract: Die Deutsche Nationalbibliothek verzeichnet diese Publikation in der Deutschen Nationalbibliografie; detaillierte bibliografische Daten sind im Internet über http://dnb.d-nb.de abrufbar.

Cited by 8 publications

References 0 publications

Efficiency and Compatibility of Selected Alkoxysilanes on Porous Carbonate and Silicate Stones

Efficiency and Compatibility of Selected Alkoxysilanes on Porous Carbonate and Silicate Stones

Exploring the Thermal Microcosms at the Forest Floor—A Case Study of a Temperate Forest

Determining the Impact of High Residential Density on Indoor Environment, Energy Use, and Moisture Loads in Swedish Apartments-and Measures for Mitigation

Contact Info

Product

Resources

About