ABSTRACT

Massive timber elements are new in Norway, but their use is increasing. More knowledge is needed regarding the moisture performance of massive timber elements. There is uncertainty regarding the need for vapour barriers or retarders, and construction tents are rarely used despite the elements’ sensitivity to moisture. Twelve massive timber cases from the Mycoteam database, evenly distributed between the construction phase and use phase, have been studied. The types and causes of damage are compared, and remedial measures studied. Examination was challenging, and long electrodes in pre-drilled holes were found as a feasible method for moisture measurements. Drying took place from one week to several months, depending on wetting and drying conditions. The main cause of moisture intrusion was insufficient protection from precipitation, either during construction or due to constructional errors. Fungal growth was observed in all but three cases, while decay was found in six cases. High moisture content within elements did not cause fungal growth if the surfaces were dry. Decay in outdoor exposed elements was mainly caused by Gloeophyllum sepiarium, whereas Antrodia sp. was most common in elements not exposed outdoors. More research is needed regarding fungal damage in massive timber elements in combination with other materials.

摘要

大型木材元素在挪威是新事物，但其使用量正在增加。需要有关块状木材元素的防潮性能的更多知识。关于是否需要阻汽层或阻滞剂存在不确定性，尽管元件对湿气敏感，但很少使用建筑帐篷。研究了来自Mycoteam数据库的十二个大型木材案例，这些案例在施工阶段和使用阶段之间平均分配。比较了损坏的类型和原因，并研究了补救措施。检查具有挑战性，发现预钻孔中的长电极是测量水分的可行方法。干燥从一周到几个月不等，具体取决于润湿和干燥条件。水分入侵的主要原因是对降水的防护能力不足，无论是在施工期间还是由于施工错误。除三例外，其他所有病例均观察到真菌生长，而六例中发现有真菌生长。如果表面干燥，元素内的高水分含量不会导致真菌生长。户外暴露元素的衰减主要是由于Gloeophyllum sepiarium，而牛樟芝。在没有暴露在户外的元素中最为常见。关于块状木材元素与其他材料结合在一起的真菌损害，需要进行更多的研究。