Water,Wind, Wood,and Trees: Interactions,Spatial Variations,Temporal Dynamics,and their Potential Role in River Rehabilitation

Recent Australian research has quantified the role of large wood (wood of any origin and length with a diameter greater than 0.1 m) in dissipating stream energy, forming pool habitats by local bed scour, protecting river banks from erosion, and damming rivers with long rafts causing avulsions. Large wood in Australian streams is sourced by a range of processes from the nearby riparian zone which has usually been degraded by post‐European settlement vegetation clearing. Large wood loadings within the bankfull channel are dependent not only on the type and quality of the riparian plant community but also on bankfull specific stream power, channel width, and the processes of large wood delivery to the stream. While bank erosion and floodplain stripping by catastrophic floods are obvious and important delivery mechanisms, treefall and trunk and branch breakage by strong winds during tropical cyclones and severe storms are also significant in the tropics. Furthermore, wood decay and downstream transport produce temporally dynamic large wood distributions. The longevity of natural large wood structures in rivers, such as rafts, debris dams, and log steps, requires determination. River rehabilitation programs need to not only include the reintroduction of large wood, but also carefully plan the spatial distribution of that wood, the most appropriate type and range of large wood structures, and, most importantly, the revegetation of the riparian zone to ensure a natural long‐term source of large wood. Exotic species management is an essential part of river rehabilitation.     

CIRCULAR MIGRATION AND LIFE COURSE OF FEMALE DOMESTIC WORKERS IN BEIJING

This study examines the migration experiences of 24 female domestic workers in Beijing through in-depth interviews. Most of these women were involved in a circular pattern of movement between their home villages and cities. The pattern of reverse and circular migration was closely related to the life-course transitions of Chinese rural women and their socially-assigned gender roles such as marriage, childbirth, childrearing and caregiving for family members. For individual domestic workers, working in Beijing is a bittersweet experience. The women were subjected to unfavourable work conditions and pervasive forms of exploitation. Nevertheless, they benefited from the experience through increased access to income, knowledge and other resources unavailable in rural areas. Although these women challenged, through migration, the traditional social roles imposed on Chinese rural women, their own limitations and institutional barriers left them with few options for improving their social statuses in cities.     

METHODOLOGY FOR THE PROBABILISTIC ASSESSMENT OF q FACTORS. A DAMAGE INDEX APPROACH

The objective of the present work is to present a methodology for the identification of relevant limit states, namely ultimate limit states leading to structural collapse, and for the assessment of design q factors (or force reduction factors) for reinforced concrete structures under seismic loading. It follows a probabilistic approach based on damage indices. The utilised nonlinear models, as well as the damage indices, which are those proposed by Miner and by Park and Ang, are.described. The methodology of analysis is presented emphasising its probabilistic characteristics. Some parametric studies are carried out, including the analysis of one regular plane frame reinforced concrete structure, designed for three different ductility classes (those proposed by Eurocode 8) and assuming different q factors in design. Results show how the chosen damage indices can be used as parameters to characterise the structural response and how the proposed methodology can be used to assess the design q factors. It is also shown that, for moderate seismic input, the three ductility classes are essentially equivalent in terms of maximum damage indices, but that for higher seismic levels the differences are evident, justifying the use of different q factors.     

SEISMIC DESIGN AND RESPONSE OF BARE AND MASONRY-INFILLED REINFORCED CONCRETE BUILDINGS. PART II: INFILLED STRUCTURES

The effects of masonry infills on the global seismic response of reinforced concrete structures is studied through numerical analyses. Response spectra of elastic SDOF frames with nonlinear infills show that, despite their apparent stiffening effect on the system, infills reduce spectral displacements and forces mainly through their high damping in the first large post-cracking excursion. Parametric analyses on a large variety of multi-storey infilled reinforced concrete structures show that, due to the hysteretic energy dissipation in the infills, if the infilling is uniform in all storeys, drifts and structural damage are dramatically reduced, without an increase in the seismic force demands. Soft-storey effects due to the absence of infills in the bottom storey are not so important for seismic motions at the design intensity, but may be very large at higher motion intensities, if the ultimate strength of the infills amounts to a large percentage of the building weight. The Eurocode 8 provisions for designing the weak storey elements against the effects of infill irregularity are found to be quite effective, in general, for the columns, but unnecessary and often counterproductive for the beams.     

Governance Structures: Using IAD to Understand Variation in Service Delivery for Club Goods with Information Asymmetry

Club goods with information asymmetry are frequently provided through mixed economies of for‐profit, nonprofit, and public providers. Theory explaining mixed economies relies on sector to classify providers based on assumptions that sector‐level differences in how organizations either distribute or reinvest profit will affect behavior. However, this classification is overly broad and is not able to adequately capture the diversity of providers of these types of goods. The author utilizes the Institutional Analysis and Development framework to identify six “governance structures” in the for‐profit and nonprofit sectors. Governance structures are constitutional‐choice level rule variations in who has the power to make rules. I argue that there are two types of power that affect rules: (1) concentration of constitutional‐choice level decision‐making power (i.e., how many principals) and (2) proximity of monitoring and enforcement of those rules. The extent to which the constitutional rules actually guide service delivery outcomes depends on a nested rule environment. Only if there is consistency across three level of rules (constitutional, collective, and operational) can we connect sector to outcomes. The empirical reality of service delivery, particularly for club goods with information asymmetry, is far too complex for simplistic assumptions linking profit distribution or its reinvestment to outcomes. This article directs further research toward building contingent theory, with if/then conditions, based on empirical research.     

Importance of Monitoring,Behavior Analysis,and Diagnostic Techniques for Preservation of Great Historical Structures

A synthetic overview is presented of the motivations, technological possibilities, and benefits of the practice of providing large structures with monitoring installation and interpretative activities. Starting from the large body of experience gained in the field of dam engineering, the gradual penetration of these techniques in the area of preservation of monumental building is surveyed. Particular attention is dedicated to the case of the Brunelleschi Cupola in the Florentine Cathedral of Santa Maria del Fiore. The more pressing needs for the next-future development of these studies and practices are then enunciated, with the auspice that the obstacle posed to their diffusion by the difficulty of collecting adequate financial funds may be overcome in the best interest of the conservation of a precious historical-cultural heritage.     

Seismic History of the Church of San Pietro Di Coppito in L’Aquila

After the terrible 18th-century earthquakes—in L’Aquila in 1703, Lisbon in 1755, and Reggio Calabria in 1783—specific anti-seismic precepts were introduced in the rules of the art of masonry construction. Scrupulously adhered to in the first years after the earthquake, those precepts gradually ceased to be used until they were almost completely forgotten, centuries later, by which time the earthquake had become a distant memory. The church of San Pietro di Coppito, one of the most important churches of L’Aquila, is emblematic of this singular process. Deeply transformed in accordance with new anti-seismic construction techniques after it was particularly badly damaged in the terrible 1703 earthquake, the church was subjected, in the 1970s, to drastic alterations by the Commissioner Mario Moretti, who demolished all the baroque additions and redesigned it in the “medieval Abruzzo” style, eliminating in the process the intelligent anti-seismic provisions introduced in the 18th century. In addition to documentary purposes, this work aims to underline the effectiveness of this early 18th-century example of anti-seismic engineering in the belief that the constructive solutions it employed could still form a valid architectural and structural model in view of the massive restoration task for which, unfortunately, L’Aquila is still waiting today.     

Tracing firing technology through clay properties in Cuzco,Peru

The purpose of this study was to identify changes in firing practices that occurred during a timeframe that saw the introduction of European kiln technology to the Andes (AD 900–1800). Pottery from an excavated context at the archaeological site of Aqnapampa in the southern highlands of Peru was examined for changes in paste recipes that adapted local materials to increased firing temperatures indicative of evolving firing technologies. Sherds (60) and fragments refired to 890 °C from 12 stratigraphic levels were compared by style, surface treatment, paste color, and vitrification structures (ESEM). Four technological phases of the Cuzco pottery sequence emerged and were used to evaluate the trajectory of a single decorative style (Killke). Previously thought to have been produced in pre-Inca times and curated into later periods, the Killke sherds presented evidence that the style was produced using technologies introduced in the Inca and Spanish Colonial Period.     

Gaiola vs. Borbone System: A Comparison between 18th Century Anti-Seismic Case Studies

This article briefly discusses the seismic-resistant heritage of the 18th century, circumscribed in Lisbon’s Baixa Pombalina (post 1755) and case baraccate of Southern Italy (post 1783).

A comparison of these anti-seismic systems is discussed through the architectural principles and the mechanical behavior. It is shown that, despite the wide diversity of cases and the different geo-historical conditioning, both systems arise from an intuition of the compound seismic efficiency, the typical pragmatism of the enlightenment period and an interpretation of the classic composition code.

Two specific case studies, a private building in Baixa Pombalina (Lisbon) and the Bishop’s Palace of Mileto (Calabria region) are compared. We briefly analyze: (i) configuration and structural principles; (ii) characteristics of the materials; and (iii) seismic behavior.

A standardized spatial morphology closely linked to traditional construction techniques positively determines the seismic response and it is one of the key common factors in this heritage to be preserved.

In both cases, the architectural and structural choices are crucial to the seismic response of the building and must be respected as an identity of a specific technical knowledge. Moreover, this materiality represents a historical continuity of the community’s memory that requires transdisciplinary, critical understanding, and preservation.