Mine blast vibration response spectrum for structural vulnerability assessment: case study of heritage masonry buildings

Ground-borne vibrations induced by mine blasting are typically of low amplitudes, which are not considered a major concern for modern engineered structures. However, historic structures are often considered more vulnerable due to inadequate knowledge regarding the state of construction materials and structural response. Specifically, the construction materials used might be fragile or have deteriorated to a stage that could be vulnerable to such vibrations. Simplistic rule based on peak ground motion parameter has been adopted worldwide for safety assessment, while the frequency characteristics of vibrations are not taken into account. Further, there is very limited study on response of heritage structures to near-field blasting. This article presents a practical structural vulnerability assessment method for mine blast-induced vibrations. In particular, a design response spectrum model is proposed based on close range measurements of nearby mine blasting, which is compared with an existing design spectrum model for far-field mine blasts and a typical design spectrum model for earthquake actions. The method is illustrated through a case study of heritage masonry buildings in Australia. The unique blast data presented and the generalized methodology would be useful to both structural engineers and blast engineers in considering potential effects of blasting on heritage structures.     

Has planning been de‐democratised in Sydney?

This paper investigates the complex and continuously evolving processes of de‐democratisation evident in urban planning practice in Sydney between 2011 and 2017. New South Wales' successive rounds of planning reform, establishment of a metropolitan commission, and amalgamation of local governments over that period have aimed to reduce local democratic participation in planning decisions, but they have had uneven success. I argue that while New South Wales' efforts to streamline development and de‐democratise planning have evolved considerably in response to multiple forms of opposition, the success of the neoliberal project is still uncertain. The insights this story offers add complexity to theorists' claims about the inevitability of depoliticisation and the end of meaningful democratic engagement. The story also offers insights about how power is created, lost, and regained in particular local circumstances.     

Prioritising Heritage Resources in a Time of Loss: Sea Level Rise and Archaeological Resources of the Middle Atlantic Region,US

ABSTRACT

The US Middle Atlantic region, known for its rich archaeological record and diverse topographic settings, is experiencing a range of climate change impacts, most notably: sea level rise and coastal erosion in its tidal zones. Documented palaeostratigraphic and palynological studies throughout the region provide a record of late Pleistocene/Holocene environmental response to changing climate, confirming observations from other disciplines that the magnitude of modern impacts exceeds past temporal and spatial patterns. The corresponding impact on archaeological resources is great, requiring a renewed effort to document threatened sites while also working with local and state governments to develop mitigation strategies. The Middle Atlantic Archaeological Conference (MAAC) created the Sea Level Rise and Storm Surge Committee to promote regional partnerships in site impact assessment and mitigation strategies. The network highlights the predicament of archaeology in this time of climate change: accelerated research and discovery in the face of catastrophic loss.     

Reassessing the chronology of the Mississippian Central Illinois River Valley using Bayesian analysis

Chronology building has long served as a major focus of archaeological interest in the Central Illinois River valley (CIRV) of west-central Illinois. Previous methods have relied primarily upon relative dating techniques (e.g., ceramic seriation) as a means of sorting out temporal relationships between sites. This study represents the first investigation into the utility of Bayesian techniques (which consider radiocarbon dates in context with archaeological information) in the CIRV. We present the results of a detailed ceramic seriation of the region, data that we use as a priori information in our Bayesian models. We then offer contiguous, overlapping, and sequential models of site occupations in the Mississippian CIRV, review the output and appropriateness of each model, and consider their implications for the pace of sociopolitical change in the region.     

CONSUMERS AS COPRODUCERS OF PUBLIC SERVICES: SOME ECONOMIC AND INSTITUTIONAL CONSIDERATIONS

The concept of coproduction of public services has captured increased attention as a potential means of increasing the effectiveness and efficiency of local government. In this article we explore the concept of coproduction in an effort to sharpen the definition of that concept and add rigor to our understanding of the effects of coproduction in local service delivery and the processes by which coproductive activity occurs.     

Dynamic Models of Agricultural Location in a Spatial Interaction Framework

Recent research demonstrates that spatial interaction models may also be made to function as location models by the addition of appropriate hypotheses about structural adjustment. An appealing feature of the approach is that dynamics are explicitly incorporated. In this paper, the attempt is made to recast a problem from classical economic-geographic theory—that of agricultural location—within a spatial interaction framework. It is shown that a wide variety of models is potentially available, and the properties of a range of these models are selectively explored.