Probability calibration of load duration modification factor for timber roofs in the Polish mountain zones

• Autorzy: Domański T.

Identyfikatory

DOI

10.2478/ace-2014-0013

• Języki publikacji: EN

Abstrakty

EN

The resistance parameters of timber structures decrease with time. It depends on the type of load and timber classes. Strength reduction effects, referred to as creep-rupture effects, due to long term loading at high stress ratio levels are known for many materials. Timber materials are highly affected by this reduction in strength with duration of load. Characteristic values of load duration and load duration factors are calibrated by means of using probabilistic methods. Three damage accumulation models are considered, that is Gerhard [1] model, Barret, Foschi[2] and Foshi Yao [3] models. The reliability is estimated by means of using representative short- and long-term limit states. Time variant reliability aspects are taken into account using a simple representative limit state with time variant strength and simulation of whole life time load processes. The parameters in these models are fitted by the Maximum Likelihood Methods using the data relevant for Polish structural timber. Based on Polish snow data over 45 years from mountain zone in: Zakopane – Tatra, Świeradów – Karkonosze, Lesko – Bieszczady, the snow load process parameters have been estimated. The reliability is evaluated using representative short – and long –term limit states, load duration factor kmod is obtained using the probabilistic model.

Słowa kluczowe

EN

reliability; snow load; long-term loading; timber structure; roof structure

PL

niezawodność; obciążenie śniegiem; obciążenie długotrwałe; konstrukcja drewniana; konstrukcja dachowa

• Wydawca: Komitet Inżynierii Lądowej i Wodnej PAN ; Politechnika Warszawska, Wydział Inżynierii Lądowej
• Czasopismo: Archives of Civil Engineering
• Rocznik: 2014
• Tom: Vol. 60, nr 2
• Strony: 195--208
• Opis fizyczny: Bibliogr. 17 poz., il., tab.

Twórcy

autor

Domański T.

• Institute of Building Materials and Structures, Cracow University of Technology, Poland

Bibliografia

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