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1.
明清古建筑木结构典型抗震构造问题研究   总被引:3,自引:3,他引:0       下载免费PDF全文
为保护古建筑,采用分类统计方法,研究了我国明清古建筑木结构的典型抗震构造问题。基于大量工程现场勘查结果,对古建筑木结构的典型抗震构造问题进行了归纳汇总,分析了原因,提出了加固建议;基于典型算例,对古建筑木结构加固方法进行了深入论证。结果表明:我国古建筑木结构的柱子、斗棋、榫卯节点、梁架、屋顶等各部位都容易产生开裂、糟朽、变形、拔榫等抗震构造问题并影响结构的抗震性能,而这些问题的产生原因主要与木结构的构造特征、木材材料性质及施工保养等因素有关;对这些抗震构造问题及时采取合理有效的加固措施,可减轻或避免结构产生的震害。  相似文献   

2.
甘肃出土糟朽木器环境腐蚀作用与机理研究   总被引:2,自引:1,他引:1  
甘肃独特的地理、气候环境,一般考古出土木器都具有糟朽木器的典型特征,通常器物因木质结构与形态的脆弱性易受外部因素侵蚀而受损,而其腐蚀状况或发生腐变往往与其所处的埋藏环境、发掘现场和博物馆馆藏环境有关。鉴于目前甘肃糟朽木器的保存状况,通过甘肃糟朽木器埋藏环境、馆藏环境及影响因素调查,馆藏环境腐蚀作用与机理的科学剖析,全面、客观和准确地揭示了藏品腐蚀受损根源及原因。环境腐蚀作用的机理如下:1)可见光、紫外线腐蚀机理是,在光辐射的作用下,纤维素发生初始光化学反应造成链断裂,并伴随产生多种化合物。2)纤维素在常温下是很稳定的,但随着温度的升高,其强度相应降低,在高温光照和氧存在的情况下,会发生氧化反应;在水分、可见光、氧气、酶及酸碱等因素同时存在情况下,温度偏高则对糟朽木器材质腐蚀起着加速作用。3)可溶盐对糟朽木器材质的腐蚀作用是通过自身的潮解和结晶过程来完成的。4)害虫及霉菌、微生物对木质文物的腐蚀作用,主要是通过分泌各种生物酶来分解木质成分中有机质实现的。5)当空气中的湿度达到70%时,灰尘及粉尘会发生潮解,当沉降在糟朽木器表面时,会引起木质纤维素腐蚀和降解。  相似文献   

3.
A wooden shovel, dating from the Early Bronze Age, has survived in a remarkable state of preservation in the copper mines of Alderley Edge, Cheshire UK. Other historic timbers recovered from the mines, whilst still intact, have fared less well. An X-ray investigation into the distribution of minerals through the shovel using portable X-ray Fluorescence (PXRF) along with the use of synchrotron-based X-ray Absorption Spectroscopy (XAS) measurements of the copper and arsenic chemical speciations has provided clues to the methods by which metals from the mining environment have entered the wood of the shovel and ensured its survival. The distribution and nature of the minerals so determined suggest that the copper and arsenic, along with a significant lead content, entered the shovel during its original use in working mineral-rich deposits, rather than through the burial environment. The insights gained are expected to be applicable to other wooden artefacts recovered from ancient copper mines in other places.  相似文献   

4.
Artefacts made of wood coming from archaeological excavations provide insights into human cultural behaviour of the past. They show how man utilised natural resources and how the development of woodworking techniques and artistic endeavour were developed. Within archaeological contexts, waterlogged anaerobic conditions generally preserve the appearance of artefacts, although wood is subject to severe decay processes. The said conditions can transform the original material into a new one, thus demonstrating specific differences from those of the “fresh” wood of the same species. In order to assess these new properties correctly, an integrated diagnostic approach is needed, one which includes a multidisciplinary (micromorphological, physical and chemical) evaluation of the state of preservation.  相似文献   

5.
作为人类文化遗产的重要组成部分,古旧木材保存状态的评价及保护至关重要。为了推进对古木材保存评价的深入研究,通过对多参数检测(微形态学、物理学、化学)在微观尺度下评价古旧木材保存状况及腐蚀机理的研究成果进行了综述,在介绍了从木材细胞形态、物理孔隙结构、化学组分含量、分子结构、分子量分布等方面对古旧木材进行评价的基础上,较为全面地阐述了检测各参数的不同表征方法,包括扫描电镜法、氮气吸附法、高效液相色谱法、气相色谱/质谱联用法等,具体分析了不同表征方法间的优缺点,说明了多参数检测古旧木材保存状况的可行性及重要性,并希望以此为切入点探讨古旧木材的宏观力学性能。研究结果在木质文化遗产和历史木构建筑的保护方面具有极大价值。  相似文献   

6.
This study describes a thorough inspection of a 20th century church in the town of Isla Cristina (in the province of Huelva, southwestern Spain), which is currently awaiting restoration. The study indicates the damage processes at work in the building structure materials (brick, concrete, steel, and wood), which are closely related to its geographical location, and analyses the deterioration of the wooden roof structure. The analysis of the wooden roof includes the results of an inspection methodology on a protected building based on traditional techniques such as visual inspection and innovative non-destructive inspection techniques (visual classification, ultrasounds and thermography). Fieldwork consisted of the visual classification of the wooden pieces according to Spanish standard UNE 56544:2007 specifications after which ultrasound and thermography techniques were applied on-site. A second stage involved laboratory tests (anatomic identification, density and bending strength) using wood samples extracted from the structure in order to check the values for the physical and mechanical properties previously recorded by non-destructive techniques (NDT). These non-destructive techniques are used in inspections of the wooden roofs of buildings to identify dampness, deterioration, density loss and defects as a means of assessing their conservation status. This work concludes that the use of ultrasound and thermography techniques constitute an accurate diagnostic tool for the on-site inspection of wooden structures and the evaluation of their condition. Thermography identifies different materials and moisture content while ultrasound detects the various degrees of deterioration and density-loss in areas of the wood with high moisture content.  相似文献   

7.
A test aquarium containing water and waterlogged historical wooden material was observed during a three-year period at Vänernmuseum, Sweden, to test the feasibility of preserving and exhibiting archaeological wood or shipwrecks in a way accessible to the public. Experiments were also set up in a laboratory environment, to provide information on single factors that could influence the long-term preservation state of wood, and other processes that may occur in the water.  相似文献   

8.
通过研究产纤维素的醋杆菌Acetobacter sp.PDA菌静置培养时的生长,然后将其与小块的饱水木材一起静置培养,测定木块处理前后的湿重及扫描电镜观察的结果,肯定了细菌纤维素对木质文物有较好的修复效果.同时初步探讨了细菌纤维素修复木质文物现阶段存在的若干问题以及研究方向.  相似文献   

9.
为了解汶川地震造成的古建筑震害及对古建筑的保护,根据古建筑震害资料,通过归纳方法,获得了古建筑不同的震害症状:对木结构而言,主要有地基破坏、柱底侧移、柱身倾斜、节点拔榫、装修开裂、梁架歪闪、瓦件掉落、填充墙破坏等;而砖石及砖木结构由于承重材料的抗拉、压、剪强度相对较差,容易产生倒塌等严重震害。在此基础上,通过勘查分析方法,获得了古建筑产生震害的主要原因:地震力过大、古建筑缺乏及时保养与加固、施工原因及砖石材料本身强度差的原因等。针对不同的震害原因,提出了相应的抗震加固建议。在上述工作基础上,得出如下结论:为提高古建筑的抗震性能,应加强对古建筑的维护与加固,及时清除各种隐患,将地震产生的破坏减小到最轻的程度。  相似文献   

10.
Preliminary studies into methods for improving and safeguarding the preservation of waterlogged archaeological wooden artefacts are presented. Mannitol, sorbitol and trehalose have been tested as replacements for polyethylene glycol (PEG) as a treatment prior to freeze-drying of wooden archaeological objects. The highest anti-shrink efficiency achieved in this short experiment was (70 ± 15) % using a 20% weight per volume solution of sorbitol after soaking for one week. The collapse or eutectic temperature of each solution used was determined using a freeze-drying microscope. Importantly, it was noted that the collapse temperature of the solutions was reduced by several degrees after use for treatment of the wood samples for one month. A freeze-drying microscope with a cold light source has been used to observe the real-time freeze-drying behaviour of various treatments inside a thin section of wood, confirming that this novel technique is indeed possible and useful. Lastly, the effects of magnesium phytate as an iron chelator have been studied. It was found that the treatment lowers the collapse temperature of a PEG 600/2000 solution by roughly 3 °C meaning that objects must be freeze-dried at a correspondingly lower temperature. Iron K-edge X-ray absorption near-edge spectroscopy analysis showed that the treatment extracted approximately half of the iron(III) ions present in the timbers.  相似文献   

11.
探索漆木器制备工艺尤其是髹漆工艺,以获取能用于文物保护修复的重要信息,针对两件待上展金漆木雕的保存现状,进行了X射线荧光能谱分析、红外光谱分析、激光拉曼光谱分析、微观形貌分析以及X射线探伤等无损分析。根据分析检测结果,按照不改变文物原状、最小干预、真实性等文物修复基本原则,对文物进行保护修复,对这两件漆木器进行清理、消杀处理,对木胎残缺处进行补配和随色,对漆皮起翘、脱落严重的部位进行漆皮回贴和漆层补全,处理后状态稳定,具有一定的耐久度,达到了展览和长期安全存放的目的。  相似文献   

12.
为保护山东青州香山汉墓出土大量精美的西汉彩绘陶器,针对出土器物的腐蚀病害现状,运用X-射线衍射分析和偏光显微分析等技术手段,对出土彩绘陶器表面的白色盐分产物和陶片本体进行了检测。检测结果表明,表面盐分产物成分为碳酸钙和硫酸钙;该批陶器烧制材料主要由砂屑及粘土构成,所用粘土为岩土矿长期风化的积聚产物;制作工艺以模为主,模、塑结合;并结合以上的几种分析结果对其腐蚀病害及产生机理进行了论述,发现陶器表面风化是云母类矿物内部化学键断裂以及保存环境中的可溶盐的破坏应力所致。本研究结果为彩绘陶器保护修复提供了科学依据。  相似文献   

13.
A sample of 11 museum artefacts was examined to assess the preservation of any adhering organic residues, particularly starch granules, and to assess the potential for the identification of cooked starchy foods. The primary aim was to examine starchy deposits, extract starch granules and examine their physical condition to increase our understanding of the taphonomy of starch granules and associated organic residues in archived material and archaeological deposits. The study shows that organic plant residues could be recovered from archived artefacts and makes a significant contribution to understanding the function of this material. Recovered starch granules showed an interesting pattern of varying organic preservation on the surface of stone and wooden artefacts. Some starch granules were found to be well preserved while others in the same sample appeared to have been affected by enzyme degrading micro-organisms. Recovered residues included fully gelatinised starch.  相似文献   

14.
甘肃出土木器依据形态与结构划分,属于典型的糟朽木器类型,材质外观特征与特性明显。制作材质鉴定表明,基本类型有①松科云杉;②松科冷杉;③柏科圆柏。通过对糟朽木器形态类型、结构属性、影响因素及发生改变原因剖析,指出了糟朽木器材质在经历了第一阶段的转折性根本改变后(含水率远低于纤维饱和点),即将面临第二阶段的转折性根本变化(含水率略高或接近于平衡含水率),而这一阶段的改变结果对器物将是毁灭性的;为了避免出土器物在短期内形态发生剧变,运用生物切片、扫描电镜分析技术对木质纤维显微结构进行了观察和研究,研究结果与结构病害腐变结果相吻合。选取与糟朽器物同期考古出土的糟朽棺板木作为分析对象,分别对其化学成分、容积重、含水率以及力学性能进行了实验测试,测得糟朽木器降解损失超过50%,含水率约为10.5%,力学强度指标与正常材质相比,均有明显的下降,且相对差异较大,最大约为正常木材强度的60%。对比分析结果,得出了结论:①糟朽木器的形态与结构状况与实验生物切片分析、电镜显微结构观察和研究结果相吻合,同时材质成分、容积重与力学性能测定结果为上述分析结果提供了有力的数据支撑;②致使糟朽木器形态和结构发生改变的主要因素是胎木含水率,其值是非恒定的并随外部环境而改变,因此含水率可用于反映糟朽木器的材质特性;③纤维饱和点与平衡含水率是影响、衡量和评估糟朽木器形态与结构的两个重要的物理参数;④鉴于糟朽木器的材质特性,后期保存应尽量避免与水分的直接接触,需要严格控制其胎木的含水率,且维持恒定、稳定的保存环境,这点对后期糟朽木器的保存是非常重要的  相似文献   

15.
针对深圳博物馆收藏两件明代加彩木雕坐像存在的虫蛀、糟朽、彩绘脱落、开裂、残损等病害,急需进行保护处理的情况。本工作在前期调研和分析检测的基础上,即分别采集了木雕坐像的胎木、加彩层、污染物等样品,利用红外光谱、拉曼、扫描电镜等分析方法对其材质组成、制作工艺及病害进行了综合分析基础上,建立了坐像保护处理工艺步骤:原始档案建立、表面清理、菌虫防治处理、木质朽蚀部位和彩绘层渗透加固、破损及残缺部位修复补全、建立保护修复档案等。选择Primal SF-016作为两件木雕坐像的渗透加固材料,选择无水乙醇作为溶剂,采用较低浓度多次渗透的方法,保证了最佳的加固和防腐防虫效果;修补材料选择聚醋酸乙烯乳液和锯木屑调和补配。处理后的木雕文物器形完整,形态稳定,色泽协调,达到了理想的保护效果。这是对传世彩绘木质文物保护技术的有益探索,对日后同类文物的加固处理有借鉴意义。  相似文献   

16.
馆藏明代加彩木雕坐像保护前期研究   总被引:1,自引:1,他引:0  
为更好地了解馆藏明代加彩木雕坐像的价值和病害情况,以期实施科学的保护和修复,利用超景深三维显微光学系统、拉曼光谱、红外光谱、X射线衍射、扫描电镜、X射线荧光能谱等分析方法对馆藏两件明代加彩木雕坐像的材质组成、制作工艺及病害情况等进行了综合分析。分析表明,两件木雕文物材质为樟科樟木属,加彩层为彩绘层,施彩工艺为先于木胎上打白灰层,而后铺一层纺织纤维,再于纤维布上涂颜料层,颜料层表面涂刷一层防护膜。其中,白灰层为石膏,纺织纤维为棉织物,所用颜料多为矿物颜料,蓝色显示物质为群青,黑色为炭黑,金色疑为铜金粉,而红色显色物质为植物染料-茜草。表面防护膜层为醇酸树脂。腐朽木材碎片和加彩层表面均有大量真菌孢子和菌丝,可以认为菌虫的侵染是引起木雕腐朽的主要因素之一。研究结果为更好地认识两件木雕文物,以及对其实施科学、有效的保护奠定了基础。  相似文献   

17.
武威磨咀子出土木器腐蚀病害与机理分析   总被引:2,自引:1,他引:1  
武威磨咀子是甘肃古代糟朽木器的重要发现地之一,鉴于北方干燥地区出土的潮湿而糟朽(缺饱和水状态)漆木器与南方潮湿地区出土的浸饱水漆木器之间的差异,致使其保护材料与技术方法不同。本工作通过对武威磨咀子出土木器腐蚀病害与机理分析,着重从病害类型、影响藏品保存因素、材质物理化学组成、材质结构缺陷性及藏品的陈列和保存环境方面进行了全面、综合的科学分析。分析结果表明:武威磨咀子出土糟朽木器腐蚀病害发生是内外因素长期影响和作用的结果,得出保持保存环境的稳定性和控制木质材质中含水量是解决保护问题的关键,可为“十一五”期间甘肃馆藏木器文物实施全面保护修复提供详实的信息和技术支持。  相似文献   

18.
Dieter Kessler 《文博》2009,(6):354-364
2007年春天开罗大学和慕尼黑大学在Tunael—Gebel联合发掘,发现一个原始的罗马坟墓有一石顶,其形式如同金字塔,命名源于希腊某一铭文。这一小石灰石墓葬包含未发生变化的埃及埋葬风格。两个沉重的石灰和镀金木乃伊被安置于两个木棺中,其中一个有一木制锦缎屋顶。该木乃伊有五彩缤纷的玻璃镶嵌,双方的床都展示着华丽的宗教仪式场景色绘画ajoure-work(这些图像被木板分割)。部分埃及和希腊的70个护身符挂在床上,用石灰制成并刷成绿色。两个石灰雕像伊希斯(高38cm)被置于头部附近。雕像是利用周围的木桩加工成型的,然后涂上颜色。它们是一个明显的混合风格的实例。它们被加工成一个典型的希腊姿势,但仍然有一埃及背景。在传统的老埃及,光谱中的每一道颜色有特定象征意义。通过它可以读出背景的循环往复变化。例如,颜色变化从红色(祭品/敌人)-白(天狼星的位置)-黑色(看不见的东西)-绿色(再生)再次到地球上五彩缤纷的形式。这一统一已经在罗马时代瓦解。新的颜色如粉色的出现,白色王冠上画的黄色等等。埃及的象征意义似乎完全消失在罗马新的墓葬彩色装饰上。  相似文献   

19.
A series of 112 waterlogged archaeological wood samples of different provenances, wood species, burial times and states of preservation were analysed with the aim of assessing the validity (in terms of limits and reliability) of procedures conventionally used in the pulp and paper industry, to evaluate the state of preservation of decayed wood. In particular, the extent of any damage wrought on decayed wood tissue by the repetitive cycles that characterize these procedures was evaluated as a function of the degradation of the samples. The results indicated that standard methodologies give reliable measurements regardless of the extent of wood decay. However, it is essential to compare these data with those of non‐decayed wood that has been measured using the same procedures to take account of the errors that are inherent in these methodologies and that affect measurements.  相似文献   

20.
The Ma?agan Mikhael B shipwreck was found in 1.5m of water, beneath 1.5m of sand, 70m off the Mediterranean coast of Israel. The hull remains are in a good state of preservation, comprising the endposts, aprons, framing timbers, hull planks, stringers, and bulkheads. The finds comprise rigging elements, wooden artefacts, organic finds, animal bones, glassware, coins, bricks, stones, ceramic sherds, and complete amphoras. The shipwreck was dated to the 7th–8th centuries AD; which makes it an exceptional source of information regarding various aspects of ship construction, seamanship, and seafaring in the area in Late Antiquity.  相似文献   

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