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21.
In the described studies with the aim of optimizing hydrated lime grout composition, the first measure was to reduce the water content of the grout using a highly efficient polycarboxylate ether-based superplasticizer, whereas the second measure was to increase the content of the inert limestone filler with an adequate grain size distribution. In this way, an attempt was made to achieve the best possible volume stability and strength properties of the hydrated lime grout, while continuing to fulfill the other necessary requirements regarding non-structural grouting works which are reported in the literature.

The results of the tests showed that a non-structural grout consisting of 1 volume part of hydrated lime CL 90-S and 3 volume parts of inert limestone filler, with 0.5% of the polycarboxylate ether based superplasticizer, fulfilled most of the established requirements, so that it is thus potentially suitable for re-attachment interventions on architectural surfaces.  相似文献   

22.
This paper describes a web-enabled learning platform providing remote access to geospatial software that extends the learning experience outside of the laboratory setting. The platform was piloted in two undergraduate courses, and includes a software server, a data server, and remote student users. The platform was designed to improve the quality of the learning experience and to increase student confidence and proficiency with software-based geospatial skills. Laboratory grades of students using the platform were significantly higher than those of students who did not use the platform, and survey responses reported that students overwhelmingly liked the convenience of the platform, which allowed them to work from any location.  相似文献   
23.
This paper shows the results of two passive experiments carried out at the European Volvi test site where a scaled building has been constructed. The first experiment was performed to study the motion of the structure excited by two small earthquakes. For one month, six strong-motion recorders were installed within the structure, at the top and at the basement. The analysis of the deformation of the structure has been assessed by computing the spectral ratio between the top and the bottom, with a special focus on soil-structure interaction. An analytical model was then proposed to reproduce the structure and soil-structure system behaviour. The soil-structure interaction was accounted for by using impedance functions. During the second experiment, we concentrated our efforts on the effect of the building vibration on the surface ground motion. An explosive shot was fired and several strong-motion recorders were installed on the ground close to the structure that allowed us to clearly identify a monochromatic wave coming from the building, in the time and frequency domains. This experiment allows us to demonstrate the non-negligible effect of the soil-structure-soil interaction that may disturb the surrounding ground motion.  相似文献   
24.
Following the Malta Convention/Valletta Treaty the preferable way for the physical protection of archaeological sites is in situ preservation. When planning in situ preservation, in addition to other issues, it is also necessary to consider changes in physical environment and their impact on in situ preserved remains. This is especially important when human interaction takes place. Recently, an increase in construction on the top of archaeological sites has occurred, thus the effects of heavy equipment compaction need to be studied in more detail.

This paper presents research on the effects of the use of heavy equipment (e.g. rammers and rollers) compaction on archaeological remains. For the purpose of our research, laboratory testing has been performed. In a custom-made steel box, artificial archaeological sites were created using layers of sandy silt and gravel. A variety of archaeological and modern artefacts were placed in these created environments. Some of them were equipped with strain gauges for deformation recording. Through a series of tests a servo-hydraulic piston was used, which simulated the dynamic loading of the artificial sites. Humidity and temperature were recorded before, during, and after each test. Since layers and artefacts were three-dimensionally recorded before and after each test, compaction of layers and movements of artefacts could be studied. With attached strain gauges and visual inspection following each test, deformations and thus damage to artefacts during different stages of loadings was recorded.

The goals of our laboratory tests were the development of a new methodological approach to study the effects of heavy equipment compaction to the archaeological sites, getting an insight into the problems of such tests, and the estimation of the applicability of their results. With the presented results, our research has been a step towards better understanding the effects of heavy equipment compaction on archaeological remains and thus to the preservation of archaeological sites in situ.  相似文献   
25.
Detailed information on the hydrogeologic and hydraulic properties of the deeper parts of the upper continental crust is scarce. The pilot hole of the deep research drillhole (KTB) in crystalline basement of central Germany provided access to the crust for an exceptional pumping experiment of 1‐year duration. The hydraulic properties of fractured crystalline rocks at 4 km depth were derived from the well test and a total of 23100 m3 of saline fluid was pumped from the crustal reservoir. The experiment shows that the water‐saturated fracture pore space of the brittle upper crust is highly connected, hence, the continental upper crust is an aquifer. The pressure–time data from the well tests showed three distinct flow periods: the first period relates to wellbore storage and skin effects, the second flow period shows the typical characteristics of the homogeneous isotropic basement rock aquifer and the third flow period relates to the influence of a distant hydraulic border, probably an effect of the Franconian lineament, a steep dipping major thrust fault known from surface geology. The data analysis provided a transmissivity of the pumped aquifer T = 6.1 × 10?6 m2 sec?1, the corresponding hydraulic conductivity (permeability) is K = 4.07 × 10?8 m sec?1 and the computed storage coefficient (storativity) of the aquifer of about S = 5 × 10?6. This unexpected high permeability of the continental upper crust is well within the conditions of possible advective flow. The average flow porosity of the fractured basement aquifer is 0.6–0.7% and this range can be taken as a representative and characteristic values for the continental upper crust in general. The chemical composition of the pumped fluid was nearly constant during the 1‐year test. The total of dissolved solids amounts to 62 g l?1 and comprise mainly a mixture of CaCl2 and NaCl; all other dissolved components amount to about 2 g l?1. The cation proportions of the fluid (XCa approximately 0.6) reflects the mineralogical composition of the reservoir rock and the high salinity results from desiccation (H2O‐loss) due to the formation of abundant hydrate minerals during water–rock interaction. The constant fluid composition suggests that the fluid has been pumped from a rather homogeneous reservoir lithology dominated by metagabbros and amphibolites containing abundant Ca‐rich plagioclase.  相似文献   
26.
辜应康  杨杰 《人文地理》2015,30(1):117-121
传统的旅游目的地形象测量只关注旅游者外显层面的认知过程,即测量旅游者外显评价,而忽略了对旅游者内隐认知的测量。本研究将内隐联结测验引入旅游目的地形象研究领域,同时结合自陈式问卷以香港和韩国为例探讨旅游目的地形象外显测量结果与内隐测量结果是否存在差异。研究结果表明,被试对香港和韩国的外显旅游目的地形象的认知不存在显著差异,而对两地内隐旅游目的地形象的认知存在显著差异。本研究有助于推进旅游者行为的内隐认知研究,同时丰富旅游目的地形象的测量方法并对旅游目的地营销具有重要的实践意义。  相似文献   
27.
本文介绍了出土漆器显微试片的制作方法,通过对试片的显微观察,可以使我们对涂膜断面、材质、下地组成及漆器制作方法进行详细的分析。  相似文献   
28.
为有效保护古建筑,采用振动台试验方法,研究了中国明清官式木构古建的抗震性能。以故宫某单檐歇山木构古建为对象,制作了1∶2缩尺比例模型。模型含浮放柱底、柱架、斗拱、歇山屋顶、墙体等所有构造,且施工工艺完全符合中国明清官式木构古建施工规定。通过施加白噪声激励,获得了模型的基频和阻尼比。通过施加不同强度等级的1940年El-Centro波,获得了模型典型节点的位移和加速度响应,讨论了模型的减震系数,评价了浮放柱底、榫卯节点、斗拱、屋顶、墙体等构造的抗震性能。结果表明:模型的振动形式表现为平面内的扭摆,其原因与歇山式屋顶质量分布不均密切相关。模型的震前基频为1.47Hz,阻尼比为4.6%。地震作用下,模型的位移及加速度响应曲线近似稳定、均匀。尽管屋顶构造则对地震力有一定放大作用,但浮放柱底、榫卯节点、斗拱等构造能发挥较好的耗能减震作用。对于不同构造而言,榫卯节点的减震性能最好,其减震系数可降至0.30;斗拱次之,其减震系数可降至0.53;而浮放柱底与柱顶石之间的摩擦耗能性能最弱,其减震系数最小值为0.66。墙体在地震波强度增大过程中发生倒塌,但不影响结构整体稳定性。因此,单檐歇山式木构古建具有良好的抗震性能。  相似文献   
29.
针对粘结硬质、钙化土锈的壁画和彩绘在保护修复中使用的去除剂和显现加固剂复合应用后对其性能进行了研究测试。从光学角度对明胶膜和加样后膜折射率进行测试,对土锈剩余层粒径与厚度进行测试,又从耐久性、柔韧性等方面对两种试剂复合用的模拟壁画进行了系统评价。结果表明:两种膜的折射率几乎相同,当土锈剩余层粒径在120μm以内,厚度在70μm内的土粒都可以通过显现加固剂进行显现,恢复其古朴原貌,且不触及颜料层。复合应用后对模拟样板老化后性能测试,数据显示各方面性能良好。  相似文献   
30.
The columns of monumental buildings in ancient Greece were provided with a pair of timber “empolia” (plugs) and a “pole” (pin), at interfaces between stone members (drums, capital). In order to reinstate this connection system, in columns capitals that were repaired, during the ongoing restoration of the classical temple of Apollo Epikourios (Greece), new poles and empolia made of titanium were installed. The titanium elements were designed to have similar shape and shear strength to the estimated respective characteristics of the ancient poles and empolia. Moreover, their effect on the seismic behaviour of the temple columns was numerically investigated. The investigation showed that, within the range of strong earthquakes which are anticipated in the area of the monument, the installation of a single pole at the interface between the capital and the uppermost drum leads to limited reduction of the expected maximum and residual deformations of the column, without altering significantly the main characteristics of its rocking response. Furthermore, poles located at every column interface ensures significant limitation of the column residual deformations. Prior to implementation of the titanium poles and empolia, the main aspects of their design were verified through specially designed experiments.  相似文献   
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