Shaking Table Testing of a Full-Scale Prefabricated Three-Story Timber-Frame Building

Shake table tests were carried out on a 7 m × 5 m three-story, timber light-frame building (7.5 m height) at the TreesLab laboratory (Eucentre) in Pavia. The aim of the research was to evaluate the seismic behavior of a typical Italian prefabricated timber building and to study the interaction between the individual structural components tested in quasi-static manner in a previous experimental study. The 1979 Montenegro Earthquake ground motion, recorded at the Ulcinj-Hotel Albatros station, was selected as the ground motion for seismic tests. The maximum peak ground acceleration was scaled to 0.07 g, 0.27 g, 0.5 g. 0.7 g, and 1 g in order to evaluate the building’s performance at different levels of seismic input. More than 100 instruments were used to monitor the behavior of the building during seismic tests measuring acceleration, displacement, and forces. The visual inspection shows that the building did not show any damage during all seismic tests. However the data analysis (dynamic identification, capacity spectrum, inter-story drift) confirm that during the 1.00 g test the structure went beyond its linear elastic limit. The results obtained from this experimental study suggest that the design hypotheses commonly adopted in practice for seismic analysis (e.g., in terms of force distributions between the walls, and also the behavior factor q) are not always consistent with the real behavior of timber frame multi-story buildings, and should be backed by more accurate knowledge of the contributions of the individual structural components.     

Quantification of Linked Column Frame Seismic Performance Factors for Use in Seismic Design

Previous research has proposed the Linked Column Frame (LCF) as a lateral load-resisting system capable of providing rapid return to occupancy for buildings impacted by moderate earthquake events and collapse prevention in very large events. The LCF consists of flexible moment frames (MF) and linked columns (LC), which are closely spaced dual columns interconnected with bolted links. The linked columns (LC) are designed to limit seismic forces and provide energy dissipation through yielding of the links, while preventing damage to the moment frame under certain earthquake hazard levels. The proposed design procedure ensures the links of the linked column yield at a significantly lower story drift than the beams of the moment frame, enabling design of this system for two distinct performance states: rapid repair, where only link damage occurs and quick link replacement is possible; and collapse prevention, where both the linked column and moment frame may be damaged.

Here, the seismic performance factors for the LCF system, including the response modification factor, R, the system over-strength factor, Ω₀, and the deflection amplification factor, C_d, are established following the procedures described in FEMA P695 [2009]. These parameters are necessary for inclusion of the system in the building code. This work describes the development of archetype structures, numerical models of the LCF systems, incremental dynamic analyses, and interpretation of the results. From the results, it is recommended that R, Ω₀, and C_d values of 8, 3, and 5.5 be used for seismic design of the LCF system. A height limit of 35 m (115ft) is recommended at this time as taller LCFs are not considered in this study.     

Performance of Structures in the Mw 6.1 Mae Lao Earthquake in Thailand on May 5, 2014 and Implications for Future Construction

An M_w 6.1 earthquake struck northern Thailand on the 5^th of May 2014. The epicenter was located near Mae Lao district in Chiang Rai province. The earthquake caused unprecedented damage to structures, the most damaging earthquake ever in recorded Thai history. Five hundred and ninety-four buildings out of 10,863 were damaged to the extent that they were unsafe for occupancy. This article presents a reconnaissance investigation of damage to buildings and bridges in the two districts—Phan and Mae Lao—which suffered the most damage. Attention is paid to the performance of buildings with similar configurations and structural design, but with different layout of unreinforced masonry infills as non-structural components.     

A Checking Method for Multiple Seismic Performance Objectives of Bridge Piers Designed According to Code Provisions

Seismic bridge design codes require that bridge piers designed according to prescribed design rules should attain specified multiple seismic performance objectives. However, design codes do not explicitly require checking the attainment of specified performance objectives for designed bridge piers. In this article, seismic performance levels have been correlated with engineering damage parameters. A checking method for multiple seismic performance objectives of bridge piers has been outlined and validated with experimental results. The application of the method has been demonstrated by checking the performance of a bridge pier designed according to a code provision for a wide range earthquake ground motions.     

Field Measurements and Numerical Simulation of Debris Flows from Dolomite Slopes Destabilized during the 2005 Kashmir Earthquake,Pakistan

A devastating earthquake occurred in Kashmir, Pakistan on October 8, 2005. This earthquake resulted from reactivation of a known active fault later defined as the Balakot–Bagh fault, which caused widespread slope failure throughout its stretch, particularly around Muzaffarabad, the provincial capital of Azad Jammu and Kashmir. This slope failure resulted in a huge amount of debris material which flows in deeply incised creeks during monsoon and hits the inhabitants along the valley in Muzaffarabad. Two GPS measurements are carried out along with channel morphometric parameters and observed changes to investigate the effect of debris flows along these creeks during monsoon. Other than the physical measurements, actual debris flow is simulated using the Depth Average Material Point Method (DAMPM) after carrying out parametric study and calibrating the model for subject topographical and geological settings. The generalized effect of different input parameters of the model on debris flow runout features is studied and discussed in detail. After ensuring validation of the numerical tool, the contribution of a single closed-type check dam to decrease runout intensity to its downstream reach is also investigated for different locations to obtain optimized selection.     

Tradition as play: pilgrimage to “England’s Nazareth”

This article explores the “invention of tradition” thesis by examining the physical and ideological reconstruction, as well as the contemporary use, of the Christian pilgrimage site of Walsingham, in Norfolk, England. We argue that a focus on the actions and motivations of cultural élites encourages a one‐dimensional view of ritual and ignores how traditions may be transformed in the process of re‐enactment by other members of society.     

论20世纪末美国文官考核制度的变革

20世纪末期美国政府在文官考核制度方面进行了理论创新与实践探索。从单一的判断功能向多元复合功能的转变,从依据长官的主观评估向依据雇员与长官及同行多重评估的过渡,是这一时期美国政府文官考核制度中出现的新变化。这一变化对提升文官的素质、提高政府的效率产生了影响。     

Performance measurement as policy rhetoric: the case of federal arts councils

Various reforms at the federal level have led bureaucracies, including arts councils, to design and implement performance measurement systems. We still know very little about whether performance measurement has any influence on the external conditions of arts councils, or whether it serves as policy rhetoric for arts advocacy. In this article, we seek to understand the answers to these questions by conducting a case study of performance measurement at the National Endowment for the Arts (NEA). We conclude that there is little evidence that performance measurement at the NEA has had any appreciable effects on agency appropriation levels. Therefore, as a policy response to federally mandated performance measurement systems, arts councils might do better in focusing exclusively on metrics that capture internal efficiency, as opposed to those that serve to demonstrate performance to external constituencies.     

Tetrahedron baked-clay objects from an early woodland context at the Jaketown site,Mississippi

Excavations undertaken in 1951 at the Jaketown site revealed a dense deposit of fragmented and intact pyramid-shaped baked-clay objects (BCOs) at the base of Mound A. This deposit was associated with the site’s Early Woodland component. Recent fieldwork at Jaketown also encountered the same tetrahedron deposit and identified an additional and distinct pit feature filled with the objects. In this article, we present the results of analyses that examine the production, composition, chronology, and function of these enigmatic baked-clay artifacts. Following a hiatus associated with massive flooding in the Mississippi Valley ca. 3200–2850 cal B.P., Jaketown was re-occupied by people who shared ceramic affinities with groups to the south and to the east and, who like many contemporaries, used BCOs as a part of their cooking technology. The tetrahedron deposit represents one of the earliest dated Tchula contexts at ca. 2600 cal B.P., and was used over a short time for a social purpose that brought populations together for food consumption as a means of encouraging cooperation.     

从"第四点计划"到和平队:美国对发展中国家援助理论与实践的转变

肯尼迪政府组建和平队,以志愿者的形式,向不发达国家提供所谓“中等人力资源”,进行技术援助,实际上是对战后美国对外援助工作反思的结果,同时也为美国对外援助注入了新的内容。它所涉及的更为深层的考虑,则是广大不发达国家未来的发展道路问题,即这些国家以什么样的方式实现现代化,是以美国为代表的资本主义发展模式,还是以苏联或中国为代表的社会主义发展模式。肯尼迪政府希望,通过和平队的工作,向第三世界国家展示美国的现代化经验和技术,诱导第三世界国家走美国式的现代化道路。