木料預裂處理對歷史建築修復品質之影響

Effects of the Lumber Properties by Pre-checking Method on the Conservation of Historical Buildings

鄭炯偉(Jiong-Wei Cheng)

中原大學/設計學院/文化資產研究所/碩士(2011年)

https://doi.org/10.6840/CYCU.2011.00023

摘要

摘要
本研究主要目的為改善人造林木（30年生以內；未成熟材比例高，節、缺點多）從生材砍伐下來至木材到達氣乾狀態（含水率<19%）乾燥過程之品質，其中開裂是木材乾燥過程中最易產生的缺點。故本研究分別在杉木及柳杉木材上割出一條0.3mm寬，達直徑 1/3或直徑 1/2深的縫來作預裂處理。因在古蹟與歷史建築修復時常用人造林木，其耐腐性較差，須以防腐處理來增加其防腐防蟲的功效，故木材乾燥品質、乾燥速率等與CNS的關係亦為考量重點；又人造林木之品等挑選大都經由大木匠師或現場人員經目視分等來判定其優劣，並未使用較客觀之科學性儀器進行非破壞檢測 （NDT），以了解木料之應力等級；若木材內部有缺陷是不易發現的，因此藉由目視分等配合科學性儀器（如超音波等）來判定木材乾燥過程中品等之優劣亦是本研究考量重點之一。
為改善人造林製材品之品質，本研究在木材進行乾燥前對人造林製材品進行預裂處理（日本工法稱為背割）來減少乾燥過程中木材開裂現象，分別探討預裂處理後對木材乾燥品質（天然乾燥與人工乾燥）、製材品等、防腐處理以及力學性質（包含非破壞與破壞試驗）以及木料應用於修復現場美學上之影響。
本論文共分五章作論述，其章節內容如下：
第一章 續論
研究動機與目的、研究範圍與方法確立本研究主題內容。
第二章 文獻回顧
整合國內外研究成果對木材乾燥品質所產生之缺點，如何改善木材乾燥品質及木材乾燥過程與品質間的關係。
第三章　實驗材料與方法
分析本研究之實驗材料、實驗設計、實驗方法與設備操作方式及流程。
第四章 木料預裂與品質之探討
實驗後數據之統計，木材預裂處理後對乾燥過程物理性質之影響、抗彎測試結果及應用於歷史建築修復工程案例作探討。
第五章 結論與建議
總結木料施以預裂處理後之優、缺點及美學上之應用，木料預裂處理對日後歷史建築修復品質之建議與方法。

關鍵字

ACQ處理 ； 人工乾燥 ； 古蹟與歷史建築 ； 預裂 ； 天然乾燥

並列摘要

Abstract
The objects of this study are to investigate the effects of pre-checking on the dry quality and mechanical properties of plantation wood（within 30-year old; immature material including knots, checks...etc.）used for the restoration of listed historical buildings in Taiwan. The wood specimens made from China fir（Cunninghamia lancelata）and Japanese cedar （Cryptomeria japonica）were used in the study. The wood specimens were first longitudinally pre-checked with a width of 0.3 mm and a depth of 1/3 – 1/2 diameters. After pre-checking processing, some wood specimens were treated with ACQ preservative. Then, the dry velocity and dry quality according to related CNS standards were investigated. For the effects of pre-checking on the mechanical properties of tested wood specimens, non-destructive and destructive testing methods were conducted. In addition, the effect of aesthetics after the pre-check lumber was also evaluated for application to conservation of historical buildings.The results would provide basic and practical information for future research, processing, and utilization of domestic the wood species used for the restoration of listed historical buildings in Taiwan.
In order to improve the conservation quality, this study using the pre-check method to reduce drying defects during drying wood, then discuss the physical and mechanical properties after air dying and kiln drying process, and evaluate the effect of aesthetics after the pre-check lumber apply to conservation historical buildings.
Summary of the five chapters：
I.Introduction
In the first chapter, the objects, research scope and methodology were introduced.
II.Literature review
In the second chapter, the former researches about the dry quality of timber, weaknesses of timber after dry processes and how to improve dry quality were reviewed.
III.Test material and method
In the thire chapter, the experiment material, the experiment design, experimental methods and equipment of this research were introduced.
IV.Effects of the lumber properties by pre-checking method
The test results of the lumber properties by pre-checking method were statistically analyzed.
V.Conclusion and suggestion
According to the test results and discussion, the application and esthetic aspects of pre-checked timber used in the timber restoration in the historical buildings were concluded and suggested.

並列關鍵字

artificial dry ； ACQ treatment ； natural drying ； Pre-checking ； Historical buildings

參考文獻

3.林翰謙（木材乾燥概論），2007，199-204。

1.王松永（木材乾燥），中華民國林產事業協會，1992，50-57。

4.Alexiou, P. N., Wilkins, A. P., and Hartley, J. (1990). “Effect of pre-steaming on drying rate, wood anatomy and shrinkage of regrowth Eucalyptus pilularis Sm.,” J. Wood Science Technology 24, 103-110.

5.Ananias, A. R. A., Espinoza, L. G., and Kauman, W. G. (1995). “Preheating ChileanEucalyptus globules at 80°C in water-saturated air,” Holzforschung 49, 179-181.

6.Chafe, S. C. (1995). “Preheating and continuous and intermittent drying in boards of Eucalyptus regnans F. Muell. Part 1. Effect on internal checking, shrinkage and collapse,” Holzforschung 49(3), 227-233.