@inproceedings{HirschmuellerMaraisBrischkeetal.2020, author = {Hirschm{\"u}ller, Sebastian and Marais, Brendan and Brischke, Christian and Krey, Adrian and B{\"o}sing, Janine}, title = {Wood protection with cement - Part 1: Coating matters and durability of cement coated wood}, series = {Proceedings IRG Annual Meeting. IRG/WP 20-60483. 51th IRG Annual Meeting}, booktitle = {Proceedings IRG Annual Meeting. IRG/WP 20-60483. 51th IRG Annual Meeting}, editor = {The International Research Group on Wood Protection,}, publisher = {The International Research Group on Wood Protection 2020}, address = {Stockholm}, pages = {1 -- 25}, year = {2020}, abstract = {The use of wood in geotechnical applications has seen renewed interest. However, concerns related to the durability and service life of wood in ground contact applications remain. Wood has the potential to substitute commonly used steel and concrete in the geotechnical engineering sector, but solutions to extending the service life and maintenance intervals require long-lasting wood protection systems capable of inhibiting fungal and bacterial decay. Cement, one of the constituents of concrete was identified as a potential coating material for wood used in soil stabilisation works. Spruce and beech wood rest rolls from commercial veneer peeling has been identified as a potential source for cement-coated geotechnical wood products. Norway spruce and European beech wood was subsequently used in this study. In this study, a series of tests related to dimensional stability and fungal durability were undertaken to investigate the adhesion of a cement coating to wood and to assess the effect of a cement coating on the resistance to fungal decay. Swelling and shrinkage tests of uncoated specimens were undertaken to investigate dimensional stability. Laboratory fungal durability tests assessed changes in wood durability of specimens coated with a novel, flexural cement coating. Wood impregnated with Polyethyleneglycol-dimethacrylate (PEGDMA) prior to cement coating was investigated to improve wood dimensional stability and reduce cracking of the cement coating under changing wood moisture conditions. Cement coating thickness and delamination tests then assessed the durability of the novel cement coating itself. Results from fungal durability tests showed that a continuous, flexural, and crack-free cement coating was imperative to a wood durability improvement. Double cement-coated spruce wood showed improved resistance to decay by basidiomycetes (Coniphora puteana and Trametes versicolor). Results from swelling and shrinkage tests showed that an improvement in dimensional stability would assist in achieving a durable cement coating and impregnation with Polyethyleneglycol-dimethacrylate (PEGDMA) is one manner to improve dimensional stability and therefore cement adhesion to the wood substrate.}, language = {en} } @article{MaderebnerGerhaherFlachetal.2017, author = {Maderebner, R. and Gerhaher, U. and Flach, M. and Hirschm{\"u}ller, Sebastian}, title = {Load carrying capacity of screwed CLT wall-ceiling joints with and without elastic supports}, series = {BAUINGENIEUR}, volume = {92}, journal = {BAUINGENIEUR}, pages = {495 -- 502}, year = {2017}, abstract = {Due to the application of elastic interlayers for acoustic decoupling, wood screws to connect timber elements are stressed beneath axial and shear loads additionally by a bending moment. The equations to calculate the load carrying capacity of wood-wood-connections according to the Eurocode 5, lose their validity in case of application of interlayers with low shear resistance. Furthermore, the increasing flexibilities of the joints should be considered for a realistic static modelling. Aim of the present work is to analyze the mechanical load bearing characteristics of wall-ceiling-connections of cross laminated timber with and without elastic interlayers. On the basis of experiments as well as analytical approaches, the load-deformation-behavior is discussed and contrasted to the current standards.}, language = {en} } @inproceedings{HirschmuellerKovrygaUnterbergeretal.2022, author = {Hirschm{\"u}ller, Sebastian and Kovryga, Andriy and Unterberger, Seraphin and Larbig, Harald and Marais, Brendan and Brischke, Christian and van de Kuilen, Jan-Willem and Krey, Adrian}, title = {Laminated veneer lumber made from cement-impregnated veneers}, series = {The 10th European Conference on Wood Modification}, booktitle = {The 10th European Conference on Wood Modification}, editor = {Gerardin, Philippe and Militz, Holger}, pages = {5}, year = {2022}, abstract = {Typically, to improve the fire resistance of wood, chemical substances, including phosphorus, borate, phenols, nitrogen and halogen based compounds, are impregnated into the wooden material. However, due to problems related to the toxic properties of these fire-retardant compounds, new fire-retardancy methods based on a mineralization process have been developed. Cementitious mineralization of wood is a novel and alternative approach for a non-toxic flame retardant, with viable application in laminated veneer lumber. This paper briefly describes the effects of different solid impregnation materials on the thermal properties and fire retardance of beech veneers (Fagus sylvatica L.). Beech veneers were impregnated with a suspension of (i) microfine binder and glycol, (ii) microfine binder mixed with calcium oxalate monohydrate and glycol, and (iii) aluminium hydroxide and glycol, in a vacuum/high pressure process. Single-flame source tests of with different solids impregnated veneers revealed a considerable improvement in flame retardancy of cementitious mineralized beech veneers compared to untreated control specimens.}, language = {en} } @techreport{HirschmuellerWalser2023, author = {Hirschm{\"u}ller, Sebastian and Walser, Georg}, title = {Rettung von Großvieh bei Brandereignissen landwirtschaftlicher Geb{\"a}ude in Holzbauweise; Teilvorhaben 1: Bauliche und konstruktive Grundlagen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:861-opus4-20627}, pages = {55}, year = {2023}, abstract = {Innerhalb des Teilvorhabens 1 (TV 1) des Verbundprojektes wurde ein Beitrag zu den baulichen und konstruktiven Grundlagen einer effektiven Rettung von Großvieh bei Brandereignissen erstellt und M{\"o}glichkeiten einer effektiven Brandfr{\"u}herkennung sowie Vorschl{\"a}ge f{\"u}r bauliche Maßnahmen erarbeitet. In enger Zusammenarbeit mit den Verbundpartnern der Hochschule Weihenstephan-Triesdorf sowie der Arbeitsgruppe Pr{\"a}ventionsingenieure e.V. wurden, soweit feststellbar, in einem ersten Schritt Daten zu Branderhebungen, aufgetretenen (Tier-)Sch{\"a}den und Brandursachen erhoben. Unter Beachtung vorhandenen Betriebsstrukturen und der nutztierartabh{\"a}ngigen, tierphysiologischen Aspekte wurden Vorschl{\"a}ge f{\"u}r konstruktive und bauliche Durchbildungen von baulichen Anlagen zur Verbesserung einer effektiven Rettung und Nachbetreuung von Großvieh, insbesondere in der Entstehungsphase von Brandereignissen, erarbeitet. Die nach eingehender Analyse bestehender Objektstrukturen erarbeiteten Vorschl{\"a}ge zur Verbesserung der Rettung von Nutztieren wurden konstruktiv in Praxisversuchen validiert. Insbesondere aus dem durchgef{\"u}hrte Pilotversuch der Evakuierung einer Rinderherde konnten R{\"u}ckschl{\"u}sse f{\"u}r weitere baulich-konstruktive Anpassungsmaßnahmen f{\"u}r m{\"o}gliche Evakuierungsstrategien gezogen werden.}, language = {de} }