Sustainable long-term use of timber structures – fire and post-fire deterministic and probabilistic solutions
| Project team: |
University of Ljubljana, Faculty of civil and geodetic engineering University of Ljubljana, Biotechnical Faculty Slovenian National Building and Civil Engineering Institute |
| Duration: | 36 months 1.10.2023 – 1.10.2026 |
| Project code: | J2 50063 |
| Lead partner: | University of Ljubljana, Faculty of civil and geodetic engineering |
| Project leader: | Robert Pečenko |
| Other project partner’s organization: | University of Ljubljana, Biotechnical Faculty Slovenian National Building and Civil Engineering Institute |
| Source of finance: | Slovenian Research And Innovation Agency – ARIS |
| Key words: | fire and post-fire design of timber buildings, sustainable design, advanced numerical models, probabilistic approach, fire resistance, advanced experimental tests, wetting of wood during extinguishing process, rheology of wood, mechano-sorptive creep |
Description:
When designing environmentally friendly and sustainable buildings, wood is almost indispensable material and often represents the whole or a large part of the load-bearing system. Thus, a challenge to better design timber buildings, in an efficient, economical, environmentally friendly, and sustainable way is always present and topical. A great challenge in ensuring sustainable timber structures represents the requirement for fire safety and fire resistance of the structure. In addition, for a sustainable and log-term use, it is also important to design a timber building so it can survive a fire event during its lifetime, while it can still be normally used after fire, without changing its load bearing elements. For this, the phenomena that take place during fire exposure as well as after fire exposure needs to be known. In terms of load-bearing capacity and stability, the moisture content has a significant impact on the long-term mechanical behaviour of timber elements. Particularly important can be the influence of high free water content, which can appear in wood as a result of extinguishing the fire. Since the problem of safety in fire and post-fire conditions is very complex, the key is merging experts of different disciplines and scientists with the introduction of innovative experimental methods and numerical models.
The main goal of the project is the development of new numerical models for predicting the long-term behavior of timber structures under fire and post-fire conditions, as well as the development of new advanced experimental methods for determining the physical, rheological and mechanical properties of wood, as well as charring and water absorption properties of wood as a consequences extinguishing process. The project is therefore divided into two parts, namely the numerical part and the experimental part.
Main goals:
The objectives of the numerical work are:
(1) Development of a new probabilistic heat-mass-pyrolysis model to determine charring of timber elements exposed to fire, accounting for random nature of fire and wood material properties.
(2) Development of a new heat-mass-pyrolysis model, considering the temperature dependent sorption hysteresis and the influence of free water transport.
(3) Development of a new mechanical model for predicting the long-term behaviour of timber structures and elements in changing environmental conditions and in case of fire.
The objectives of the experimental work are:
(1) Create a new database for physical, elastomechanical and rheological properties of structural timber that was exposed to fire.
(2) Establish a new database for charring of structural timber.
(3) Conduct the series of test to monitor the water intake during the extinguishing process of timber elements exposed to fire.
Project packages:
WP 1. Project management and organization
WP 2. Experimental determination of wood material properties
WP 3. Experimental investigations of charring of structural timber and water intake during extinguishing
WP 4. Development of new advanced numerical models