排序方式: 共有101条查询结果,搜索用时 15 毫秒
71.
江苏镇江东晋画像砖发掘简报曾从历史背景出发,简略指出镇江东晋墓兼具山东和先秦楚文化特点。在简报认识的基础上,再补充若干重要实例并进行分析,可以发现六朝时期今镇江地区自成文化圈,镇江东晋画像砖墓是观察汉晋文化嬗变之迹的典型材料。 相似文献
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József Simon 《International Journal of Architectural Heritage》2016,10(4):457-475
This study focuses on domes the ground plan of which, instead of the more common circular shape, is an oval, and aims at finding the minimally necessary uniform wall thickness for domes of different geometries loaded by their selfweight. The discrete element code 3DEC was applied because of its capability of simulating the collapse mechanisms of masonry structures. Results on the minimal wall thickness, corresponding masonry volume and failure mechanisms for different dome geometries are presented. Three ranges of the friction coefficient were found. For very low frictional resistance collapse happens with pure frictional sliding, for any arbitrarily large wall thickness. In the range of relatively high (i.e., realistic) friction coefficients the structure collapses without any sliding if the wall is not sufficiently thick, and in the observed range of the friction coefficient the necessary wall thickness is nearly insensitive to its value (collapse initiates with hinging cracks only). Between the two domains an intermediate behavior was found: combined cracking and sliding collapse modes occur for insufficient wall thickness, and the minimal thickness strongly depends on the friction coefficient. The critical and transitional friction coefficients separating the failure modes were determined for different eccentricities of the groundplan. 相似文献
73.
黄龙 《文物保护与考古科学》1996,8(2):37-44
金属成形加工技术是人类文明的杰出贡献,在中国,传统金属加工技术门类繁多,其中发展最深、应用最广的首推铸造技术。考古发掘与文物研究证明:中国悠远灿烂的青铜文化其基础为铸造技术,而泥质铸型处理技术又是中国传统铸造技术的关键之一。本文拟通过现存传统泥质铸型处理技术的研究、古代文献资料的分析、出土泥质铸型(陶范)的科学测试,对中国传统泥质铸型处理技术的形成作初步探源工作。 相似文献
74.
本文系统论述了六朝时期建康及外围地区大型砖窑墓的建筑结构和筑造技术,认为这一时期墓葬非常富有地域特色,并传之于隋唐。 相似文献
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Scanning electron microscopy is used to examine sequences of pottery sherds from central and southeast Europe, Greece and the Near East spanning the period from the Neolithic to the Bronze Age, in order to obtain information on the ceramic technologies employed in antiquity. On the basis of the vitrification observed and the chemical composition, the types of clay and firing procedures (temperature and atmosphere) employed in the manufacture of the pottery are defined. Two under-lying trends in the associated ceramic technologies are thus identified. The first is based on the use of non-calcareous or “unstable” calcareous clays fired in a reducing atmosphere at temperatures below 800 °C and the second on the use of “stable” calcareous clays fired in an oxidizing atmosphere at temperatures in excess of 800 °C. 相似文献
78.
赵凡 《文物保护与考古科学》2021,33(1):110-117
为了解广汉龙居寺中殿建筑热湿环境特征,采用基于物联网技术的环境温湿度监测系统对建筑空间温度和相对湿度进行监测,分析建筑空间温湿度时空变化规律,评估建筑热湿环境特征,探讨热湿环境对文物保存的影响。结果表明,该建筑对外界环境温湿度变化具有较好的缓冲和隔离作用,建筑内部热湿环境对文物保存不利,主要体现在相对湿度高、波动大,湿度调控将是文物预防性保护的关键。建筑热湿环境为壁画酥碱和霉斑病害主要成因,同时促进了编竹夹泥墙体结构安全问题的发生。研究成果不仅丰富了对四川地区明代编竹夹泥墙木结构古建筑热湿环境特征的认识,而且为该建筑壁画病害和墙体结构安全问题的成因分析提供了依据。 相似文献
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Anastasios Drougkas Pere Roca Climent Molins 《International Journal of Architectural Heritage》2016,10(7):887-902
A masonry pillar composed of solid clay bricks, cement mortar and infill is extracted from a historical structure and tested in concentric compression. It is subjected to cyclic and monotonic loads up to compressive failure.In parallel, samples are extracted from the pillar and are subjected to destructive tests. Non-destructive tests are performed on the pillar, as well. The properties of the constituent materials are critically examined and their role in the maximum load reached and the failure mode obtained are discussed.Finally, a finite element micro-model of the pillar is used for the simulation of the pillar test. The influence of the existing damage on the pillar is investigated using the model, resulting in a fair approximation of the global Young’s modulus, maximum load and the failure mode.Highlights●?A brick masonry pillar extracted from a historical building is tested in compression.●?Material samples extracted from the pillar are characterized by mechanical tests.●?A finite element micro-model of the pillar is used for the simulation of the compressive test.●?The effect of damage on the compressive strength of the pillar is numerically investigated. 相似文献
80.
Permeability of the Mercia Mudstone: suitability as caprock to carbon capture and storage sites
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The Upper Triassic Mercia Mudstone is the caprock to potential carbon capture and storage (CCS) sites in porous and permeable Lower Triassic Sherwood Sandstone reservoirs and aquifers in the UK (primarily offshore). This study presents direct measurements of vertical (kv) and horizontal (kh) permeability of core samples from the Mercia Mudstone across a range of effective stress conditions to test their caprock quality and to assess how they will respond to changing effective stress conditions that may occur during CO2 injection and storage. The Mercia samples analysed were either clay‐rich (muddy) siltstones or relatively clean siltstones cemented by carbonate and gypsum. Porosity is fairly uniform (between 7.4 and 10.7%). Porosity is low either due to abundant depositional illite or abundant diagenetic carbonate and gypsum cements. Permeability values are as low as 10?20 m2 (10nD), and therefore, the Mercia has high sealing capacity. These rocks have similar horizontal and vertical permeabilities with the highest kh/kv ratio of 2.03 but an upscaled kh/kv ratio is 39, using the arithmetic mean of kh and the harmonic mean of kv. Permeability is inversely related to the illite clay content; the most clay‐rich (illite‐rich) samples represent very good caprock quality; the cleaner Mercia Mudstone samples, with pore‐filling carbonate and gypsum cements, represent fair to good caprock quality. Pressure sensitivity of permeability increases with increasing clay mineral content. As pore pressure increases during CO2 injection, the permeability of the most clay‐rich rocks will increase more than carbonate‐ and gypsum‐rich rocks, thus decreasing permeability heterogeneity. The best quality Mercia Mudstone caprock is probably not geochemically sensitive to CO2 injection as illite, the cause of the lowest permeability, is relatively stable in the presence of CO2–water mixtures. 相似文献