遗址博物馆土遗址病害调查与成因分析——以萧山跨湖桥遗址博物馆为例

潮湿环境土遗址的保护一直是非常困难的课题。当遗址与其他材质的文物共存时,保护难度更高。为了探讨遗址博物馆内病害发生的规律和影响因素,为未来潮湿环境土遗址保护措施的研究和设计提供依据,以杭州市萧山区跨湖桥遗址为例开展调查研究。发现盖棚可以防止雨水对土遗址的破坏,但造成了水和盐的单向迁移,是目前土遗址病害的主要根源。对于室内遗址博物馆,如何解决遗址土体水分单向迁移带来的破坏已经成为迫切需要开展研究的课题,建议尽快开展室内土遗址补水技术的实验研究。     

“Refusing to be a victim,refusing to be an enemy”. Form-of-life as resistance in the Palestinian struggle against settler colonialism

This paper focuses on practices of non-violent resistance as they are played out in the ongoing Palestinian struggle against the Israeli settler colonialism in the occupied West Bank. By looking at the resistance of expanding settlements, demolition and land confiscation orders, and livelihood destruction in two Palestinian sites, the paper shows how Israeli settler colonial apparatuses, and the variety of techniques and practices of erasure they mobilize, can be fruitfully studied through site-specific ways of Palestinian resistance. In order to do so, the paper turns to discuss a peculiar form of non-violent resistance grounded in what Giorgio Agamben calls ‘destituent power’. It shows how the acts of destituent resistance in the two sites under study function by playing with the apparatuses of control in creative but non-violent ways; namely, by using the potentialities of that form-of-life that the settler colonial apparatuses try to cancel, overrule, control, weaken, criminalize, and erase. The idea of ‘destituent play’ is hence elaborated, and special attention paid to its ability to slow down and hamper the repressive functions of the settler colonial apparatuses through the creative use of the potentialities of Palestinian everyday life.     

河南淅川县马川墓地118号东周墓

2007～2008年在淅川县马川墓地发现了近百座东周墓。墓葬保存基本完整,其中以118号墓的规模较大。该墓为带墓道的长方形多台阶竖穴土坑木椁墓,由墓道、墓室两部分组成。墓内有一椁三棺,出有陶器、青铜兵器、铜铃及料珠、玛瑙珠等遗物。该墓年代应为战国早期,墓主人为卿大夫级。     

山东高青县陈庄西周遗址笔谈

山东高青县陈庄遗址的发掘成果继在由中国社会科学院主办的中国社会科学院考古学论坛.2009年中国考古新发现活动中,被评为六大考古新发现之后,又被评为2009年度全国十大考古新发现之一,在学术界引起了广泛的关注。为做好陈庄遗址的发掘工作,山东省文物考古研究所在发掘工作期间多次邀请知名专家到现场     

楚郢都探索的新线索

本文通过对崇源铜器群的分析,认为该铜器群可能出自荆门市沙洋县十里铺镇的白玉冢,其墓主等级为上大夫且与楚王关系密切,铜器群年代为战国早期晚段。荆州区马山镇蔡桥村发现的蔡桥台基遗址群,年代早于纪南城。清华简《楚居》所述历代楚君的居处,多达14个,唯独不见戚郢,似乎表明戚郢的出现不得早于《楚居》成篇之时。有可能戚郢的出现在鄩郢之后。戚郢有可能位于目前多数学者认定的秦将白起所拔的楚都纪南城之内。那么,纪南城的始建年代就不会早于楚肃王时期,也不会晚于楚宣王早期,废弃年代则为公元前278年,而江陵蔡台基址群,也有可能是早于戚郢的鄩郢。春秋时期的楚郢都,在宜城楚皇城附近可能性较大。     

土遗址表层加固微波设备的研发

由于黏土矿物的吸水膨胀性及土体颗粒之间胶结性较差而导致土遗址极易发生剥落、粉化等表层劣化。化学渗透加固作为防治这类病害的一种重要保护措施,虽然取得了一些成果,但整体应用仍处于探索和研究阶段,尤其是材料老化周期较短及再处理的难度都极大地制约了这种方法的使用。针对这一现状,本研究探讨了一种新型保护措施——开放式微波加固。微波可以通过热效应和非热效应改变土体黏土矿物的显微结构,从而增强其抵抗环境作用的能力。同时,微波具有精准定位、能量可控等优点,还可以避免化学材料挥发对土体和环境的危害,因此可以安全有效地实施加固,从而具有良好的应用前景。本研究论述了用以加固土遗址的微波设备研发的关键技术,包括频率的选定、设备参数的确定、辅热材料的选择等,以便为此类设备的推广研发提供一些借鉴。     

土质文物盐害中硫酸钠的研究——从微观到宏观

土遗址和壁画遗址可溶盐主要为NaCl和Na_2SO_4,其中Na_2SO_4是破坏程度最严重的盐。一般认为,硫酸钠只有在温度、湿度变化时才不稳定,才发生得失结晶水引起的晶型及体积变化。为研究土质文物盐害的形成机制及内在原因,调研了全国几处典型土遗址和壁画遗址的盐害状况并取样分析。分析发现:1)土遗址和壁画遗址中硫酸钠的形貌、结构是动态变化的(无论在任何极端干燥环境甚至真空条件下);2)环境因素如温度、相对湿度的变化只是加剧上述变化进程。硫酸钠结晶析出时,其体积膨胀约4倍。这一系列的过程,深刻影响着硫酸钠的相变复杂性和对依存土质文物本体的破坏性。本工作从微观和宏观两个层面探讨了这些发现,并通过不同盐分(不同浓度氯化钠、硫酸钠)侵蚀破坏模拟试验、不同温度条件下模拟试验、不同相对湿度下模拟试验,从宏观层面印证了上述微观机制在土遗址和壁画遗址本体的外在表现。本研究发现土遗址中硫酸钠的形貌、结构是动态变化的,该工作弥补了以往研究和认识上的局限。本研究将对阻止、延缓及预测土质文物盐害的发生、发展提供科学参考。     

潮湿环境模拟考古土遗址夯筑支顶加固效果评估

为研究潮湿环境土遗址加固效果评估方法,在杭州地区进行现场模拟探方加固实验,并对加固后坑壁的波速、含水率、相对水平位移进行监测,对加固的模拟探方稳定性做出评估,以望通过采用科学定量手段评价土遗址夯筑支顶加固效果,为土遗址夯筑支顶加固效果评估提供参考。试验结果表明:模拟探方坑壁表层含水率随深度的增加而升高,含水率变化量逐渐减小;加固后坑壁土体初始强度随深度的增加而提高,且后期硬化过程也较上部区域快,土体强度随时间在逐渐增加;夯筑后坑壁前四五天位移值逐渐增大,且位移值随深度的增加而升高,后期趋于稳定。研究表明,基于变形监测技术评估夯筑体整体稳定性科学合理,基于表层含水量和波速变化评估夯筑土体强度变化是较好的手段。评估结果可为其他潮湿地区土遗址夯筑加固效果评估方法提供参考。     

A Test of the Applicability of NGA Models to the Strong Ground-Motion Data in the Iranian Plateau

The Next Generation Attenuation (NGA) project has now published several new sets of empirical ground-motion prediction equations (GMPEs) for PGA, PGV, and response spectral ordinates. These models significantly advance the state-of-the-art empirical ground-motion modeling and account for many effects that have not been directly accounted for in the existing Iranian GMPEs. Assuming that the present strong-motion database in Iran is unlikely to drastically change in the near future, the question we ask in this study is: Can the NGA models be applied in Iran? In order to answer this question, the NGA models of Boore and Atkinson [2008] Boore, D. M. and Atkinson, G. M. 2008. Ground-motion prediction equations for the average horizontal 99 component of PGA, PGV, and 5%-damped PSA at spectral periods between 0.01 s and 10.0 s. Earthquake Spectra, Earthquake Engineering Research Institute, 24(1): 99–138. [Crossref], [Web of Science ®] , [Google Scholar], Campbell and Bozorgnia, [2008] Campbell, K. W. and Bozorgnia, Y. 2008. NGA ground motion model for the geometric mean horizontal 139 component of PGA, PGV, PGD and 5% damped linear elastic response spectra for periods ranging from 0.01 to 10 s. Earthquake Spectra, Earthquake Engineering Research Institute, 24(1): 139–172. [Crossref], [Web of Science ®] , [Google Scholar], and Chiou and Youngs [2008] Chiou, B. and Youngs, R. R. 2008. An NGA model for the average horizontal component of peak 173 ground motion and response spectra. Earthquake Spectra, Earthquake Engineering Research Institute, 24(1): 173–216. [Crossref], [Web of Science ®] , [Google Scholar], which are shown to be representative of all NGA models, are compared with the Iranian strong-motion database. The database used in this study comprises 863 two-component horizontal acceleration time series recorded within 100 km of epicentral distances for 166 earthquakes in Iran with magnitudes ranging from 4.0–7.4. The comparisons are made using analyses of residuals. The analysis indicates that the NGA models may confidently be applied within the Iranian plateau. To provide more reliable constraint on finite-fault effects and nonlinear site response in the Iranian equations, it would be useful to drive new GMPEs based on a merger of the NGA and Iranian databases.     

Maximum Possible Ground Motion for Linear Structures

This article develops a method to generate ground motion time histories that maximize the response of a given linearly elastic structure. The root mean square (RMS) level of the input power spectral density (PSD) is used as a strong motion parameter. It is related to seismological data that is readily available. An empirical relation to estimate RMS value of the PSD from peak ground acceleration, magnitude, rupture distance, and shear wave velocity is derived from world-wide strong motion data. The ground motion is obtained by solving the inverse problem such that the structural response is maximized under the constraint of fixed value of RMS level of the input PSD enforced using a Lagrange multiplier. The proposed methodology is illustrated for a single-degree of freedom system, a six storey building and an earthen dam. It is shown that the critical PSD obtained in all the cases is a narrow band process resulting in stochastic resonance and not a Dirac-delta function with the entire energy of the system concentrated at its natural frequency. Moreover, the critical excitation samples generated using this critical PSD resembles actual earthquake acceleration time histories.