A new quality factor for the building stone industry: a case study of stone blocks,slabs, and tiles

In building stones, discontinuities, non-uniformity, and irregular shape are among the problems that reduce the quality of products. Stone blocks, slabs, and tiles are the main products of quarries and stone processing plants. Quantifying the quality is a key factor in valuation of these products. This paper proposes a quality factor formula to determine the quality of stone blocks (three-dimensional) and products from stone processing plants (two-dimensional). This factor, which shows the uniformity and esthetic index of a piece of stone, is determined based on the shape quality (α), number, size, and esthetic quality (β) of the pieces and the discontinuity factor (γ) that separates the pieces. The quality factor is defined in a way that each previously mentioned characteristic of a piece is involved in the quality factor formula calculation. The quality factor ranges between 0 and 1 and can be expressed as a percentage. The proposed quality factor was calculated for a number of different stone blocks, slabs, and tiles to examine the validity of the quality factor formula. The results showed that the shape quality is the most significant parameter in determining the quality of stone blocks in quarries. Moreover, in processing plant products the esthetic quality and the number of stone pieces in a product are the key factors for determination of their quality. The discontinuity factor is a parameter that reduces the quality of stone products significantly. Furthermore, the quality factor formula can be used as a convenient tool for classifying the products of quarries and stone processing plants.

     

General material properties of Denizli (SW Turkey) travertines as a building stone

The quality and material properties of Denizli travertine as a natural building stone have been investigated. The Denizli region is one of the world’s major travertine deposits and production basins. Travertine blocks are extracted from over fifty quarries in the region. In this study, investigations and evaluations of experimental test results of travertine samples from six areas (Kakl?k–Kocaba?, Honaz–Emirazizli, A?a??da?dere, Akköy, Karaçay and Çivril), which represent the entire Denizli basin, are presented. Kakl?k–Kocaba? is the biggest production area in the region, and therefore most of the quarries are located in this area. Physical, mechanical, micro-structural and macro-structural properties of the travertine samples are evaluated within the scope of stone quality assessment. Variations of test results by area are presented, and correlations between them are proposed. Test results are also compared with the results of various studies from Turkey and other parts of the world.     

Characteristics and the environmental acceptability of the natural stone quarrying waste rocks

The paper summarises the results of a study by the Geological Survey of Finland on the potential use of waste rocks from natural stone quarry production. Petrographic, chemical, mechanical and physical tests were undertaken on granite, rapakivi granite, migmatite, syenite, diorite, gabbro, anorthosite gabbro, schist and soapstone from 33 dimension stone quarries in Finland. The results indicate the waste rocks of Finnish natural stone quarries can generally be considered environmentally sound with potential uses in other industries.     

THE GEOGRAPHY OF INSECURITY: SPATIAL CHANGE AND THE FLEXIBILIZATION OF LABOR IN METRO MANILA

ABSTRACT: There has been considerable attention in the urban studies literature to the implications of spatial change associated with globalization for the urban poor in advanced economies, but much less so in developing countries despite the fact that this is where most urbanization is occurring. This article attempts to address this issue in the context of Metro Manila, a globalizing city of 10.7 million that sits in a larger mega‐urban region of some 17 million. It does so through an analysis of data collected through two methods: a sample survey of six low‐income settlements in the Metro Manila region that collected information about housing conditions, income, and employment of household members, commuting, and household heads' opinions regarding spatial change; and in‐depth interviews with a subset of respondents that were intended to generate narratives and stories that would elucidate the experience of households with spatial change. The study identifies three main issues confronting the surveyed households: the social impacts of the flexibilization of labor in the Metro Manila region, gender and age differences in access to employment, and the prevalence of extremely long commutes on the urban fringe. The article concludes that the issues faced by Metro Manila households are in many ways quite distinct from those in cities in advanced economies. It further argues that these differences have important implications both for urban policy and practice in addressing equity issues, and for theories of globalization and issues of spatial change and social equity in cities.     

NEIGHBORHOOD‐BASED NETWORKS,SOCIAL RESOURCES,AND LABOR MARKET PARTICIPATION IN TWO DUTCH NEIGHBORHOODS

ABSTRACT: Numerous neighborhood effect studies have reported on the negative consequences of living in disadvantaged neighborhoods for various employment outcomes, such as the duration of welfare dependence and level of income. One hypothesis for explaining this relationship is the social isolation hypothesis, which assumes that low‐income residents in disadvantaged neighborhoods are worse off than their counterparts in mixed neighborhoods because they rely on other disadvantaged neighbors to find work. These ideas are addressed by comparing survey data on social resources in the social networks of residents in a low‐income neighborhood and a socioeconomically mixed neighborhood in the Dutch city of The Hague. Findings show that living in a low‐income neighborhood influences labor market participation indirectly by limiting residents' access to job information. However, differences in access to job information cannot be explained by the high degree of neighborhood orientation in the social networks of residents in the low‐income neighborhood.     

A GEOGRAPHY‐SPECIFIC APPROACH TO ESTIMATING THE DISTRIBUTIONAL IMPACT OF HIGHWAY TOLLS: AN APPLICATION TO THE PUGET SOUND REGION OF WASHINGTON STATE

ABSTRACT: This study contributes to the debate about tolls’ equity impacts by examining the potential economic costs of tolling for low‐income and non‐low‐income households. Using data from the Puget Sound metropolitan region in Washington State and geographic information systems methods to map driving routes from home to work, we examine car ownership and transportation patterns among low‐income and non‐low‐income households. We follow standard practice of estimating tolls’ potential impact only on households with workers who would drive on tolled and nontolled facilities. We then redo the analysis including broader groups of households. We find that the degree of regressivity is quite sensitive to the set of households included in the analysis. The results suggest that distributional analyses of tolls should estimate impacts on all households in the relevant region in addition to impacts on just users of roads that are currently tolled or likely to be tolled.     

Geometric quality assessment of in situ blocks in dimension stone quarries

The profitability of stone quarries depends on the appearance (color and texture) and, more importantly, on the size of the blocks, which is determined by the three-dimensional discontinuity pattern of the rock mass. However, to date there is no comprehensive criterion by which to assess the size of blocks in quarries. The aim of the study reported here is to identify factors that facilitate decision-making on the desirability of an individual block and ultimately on all blocks for extraction as a dimension stone. To this end, we first developed a novel algorithm to calculate the largest rectangular parallelepiped that can be placed inside a block and then defined a regularity factor (α) and a quarry block shape factor (q) that enable the geometric quality of the block to be assessed more accurately than currently possible. The sensitivity analysis of these factors showed that the change in angle relative to the change in spacing has the greater effect on the geometric quality. The proposed factors displayed a good performance in a comparison analysis of four sites of the Dareh Bokhari travertine quarry complex located in Mahallat, Markazi province, Iran. Based on the results, blocks at sites 2 and 4 have the lowest and the highest geometric quality, respectively, which is in accordance with the operational conditions at the respective sites. Moreover, comparison of the values of factor q obtained from applying various cutting planes indicated that to maximally increase block production capacity, the current cutting direction at site 4 should be adjusted 33° eastward.

     

Trade openness and regional income spillovers in Brazil: A spatial econometric approach*

This paper employs a spatial Durbin growth model to estimate the impact of trade openness on regional per capita income in Brazil using a data set of 469 Brazilian micro‐regions over the period 2004–2007. We calculate the direct, indirect and cumulative impact on per capita income of trade openness and human capital in these micro‐regions. Results indicate that greater trade openness in a region promotes economic development locally, while exerting negative influence on per capita income of the neighbouring regions. Our findings also show that human capital has a positive – direct and indirect – impact on the economic development of Brazilian micro‐regions.     

Dust formed during drilling in natural stone quarries

Bulletin of Engineering Geology and the Environment - Dust mass concentration and concentration decrease was studied in two natural stone quarries in Finland. The dust mass concentrations produced...     

Ecological Restoration of Central European Mining Sites: A Summary of a Multi-site Analysis

Sites disturbed by mining were surveyed in the Czech Republic, central Europe. The sites included spoil heaps from coal mining, sand and gravel pits, extracted peatlands and stone quarries. The following main conclusions emerged: i) potential for spontaneous succession to be used in restoration projects is between 95 and 100% of the total area disturbed; ii) mining sites, if mining is properly designed and then the sites are left to spontaneous succession, often act as refugia for endangered and retreating organisms, and may contribute substantially to local biodiversity.     

Underground aggregate mining in Athens: a promising investment plan

The introduction of stricter environmental regulations regarding the operation of open-pit quarries in the wider area of Athens has resulted in the closure of many quarrying operations. The aggregate production cannot further ensure the meeting of demand in the area and alternative schemes are being examined so as to provide long-term solutions to that issue. This paper focuses on the development of underground aggregate exploitations in the region, providing the basis for an in depth financial appraisal supported by the mine design process which also involves the utilisation of the underground space. It is proved that beyond the environmental advantages offered by this particular solution, underground limestone mining is also an attractive investment plan. Critical importance to the latter plays the space utilisation process that can be looked as a real estate development project.     

The role of the Alaska seafood industry: a social accounting matrix (SAM) model approach to economic base analysis

A social accounting matrix (SAM) model for Alaska is constructed to investigate the role of the state’s seafood processing industry. The SAM model enables incorporation of the unique features of Alaska economy such as (a) the existence of a large nontraditional economic base, (b) a large leakage of labor income, and (c) a very large share of intermediate inputs imported from outside the state. The role of an industry in an economy with these features cannot be examined correctly within an input–output framework, which is the method most often used for examining the importance of an industry to a region. Taking an export base view of the economy, we found seafood processing to be an important industry, generating 4.5% of the state’s total employment. While an important driver of the state’s economy, the industry has the smallest SAM multiplier mainly due to a large leakage of labor earnings and a large share of imported intermediate inputs. We also found that nontraditional economic base components such as (a) federal transfers to state and local governments, and (b) federal transfers, permanent fund dividend (PFD) payments, and other extra-regional income received by households generate about 26% of the state’s total employment and earnings.     

Investigating on possible use of Diyarbakir basalt waste in Stone Mastic Asphalt

Stone Mastic Asphalt (SMA) improved for road construction which has been utilized in Europe and America for 40 years is a rather new process in Turkey. SMA basically consists of 93–94% aggregate and mineral fillers, 6–7% bitumen and additives. Road and construction industry consume stone in large amounts. Stone used are obtained from nearby quarries and carried to the location where they are to be used, destroying the nature and causing large costs. The constantly increasing demand on quarries harms the general structure of the earth thus causing the emergence of large scale environmental problems. The use of basalt waste from stone processing plants as aggregates and mineral filler in SMA might help to meet this increasing demand thus solving environmental problems. In this study, primarily some important material properties of fine and coarse basalt waste, taken from basalt processing plants in Diyarbakir, such as sieve analysis, chemical analysis, specific gravity, water absorption, Los Angeles abrasion loss value, soundness of aggregate by Na₂SO₄, flakiness index and stripping strength were determined. Then by using this waste material, a SMA was designed according to Turkish Highway Technical Specifications. Marshall stability and flow tests have been carried out on designed SMA specimens. Test results indicate that properties of the basalt waste and the SMA produced were within the specified limits and that these waste materials can be used as aggregates and mineral filler in SMA.     

EARLY RESIDENT EXPERIENCES AT A NEW MIXED‐INCOME DEVELOPMENT IN CHICAGO

ABSTRACT: Mixed‐income development is an increasingly popular poverty deconcentration strategy in the United States but there have been few in‐depth studies about the experiences of residents once they move in to the new housing developments. This article explores the early experiences of residents of all income levels who have moved into a new mixed‐income development on the south side of Chicago. In‐depth interviews have been conducted with 46 residents of the development, including 23 former public housing residents. Interviews were also conducted with a comparison group of 69 public housing residents who did not move to the development. I find that public housing movers appear to be a substantially different group than non‐movers. I find that overall satisfaction with the new development is quite high among residents of all income levels. Early social relations are limited, particularly across income levels, and there are key barriers to interaction, such as physical design, stigma and assumptions based on class and housing status, and segregated associational structures.     

Environmental degradation related to human activities, Fortaleza Metropolitan region, state of Ceará, Brazil

This paper discusses the main environmental problems that have been responsible for the degradation of the environment in Fortaleza Metropolitan region, in the state of Ceará, Brazil. Coastal erosion, gravitational mass movements, sedimentation, pollution of water, inappropriate landfilling and abandoned quarries and mines are the main environmental problems. A significant investment is required to rehabilitate these areas and alleviate the social and economic effects on the population. Electronic Publication     

Linear stone cutting tests with chisel tools for identification of cutting principles and predicting performance of chain saw machines

Different natural stone quarries are visited for collection of stone samples, determination of geological conditions, specifications and operational conditions of the chain saw machines and recording machine cutting performance with a data acquisition system. The samples are tested with a linear cutting test rig using chisel-type cutting tools with 0°, 15°, 30° and 45° sideways angles at different depths of cut and tool spacings, to determine stone cuttability, cutting characteristics of chain saw machines and effect of unsymmetric and symmetric sideways angles and different cutting patterns on cutting performance (tool forces, specific energy, optimum cutting geometry). A deterministic model is suggested for predicting performance of chain saw machines using the results of linear stone cutting experiments, and the laws of kinematics. The results of experimental studies and in-situ investigations indicate that the cutting action of chain saw machines can be successfully simulated by linear cutting experiments and the suggested model is proven, though requiring some additional study, to be a useful and reliable tool for selection, design, and performance prediction and optimization of chain saw machines.     

Analyse des effondrements de carrières souterraines de gironde,France

There is a lot of stone unterground quarries in the Gironde Region (SW-France). They are shallow, and develop numerous cavities in the underground space of 112 communes (about 2000 ha area). In this paper is given an analysis of the collapses which occurred since 1836. The synthesis is established from archives. Four instability factors are examined. They are, in decreasing order, geometry of the quarry, hydrology, geology and cracking.     

THE COMMUNITY LAND TRUST AS A HIGHWAY ENVIRONMENTAL IMPACT MITIGATION TOOL

ABSTRACT: The proposed Newtown Pike Extension in Lexington, Kentucky, has the potential to cause significant displacement of low‐income residents. Following Executive Order 12898, federal agencies have been required to consider environmental justice impacts of their policies and activities. Highway planners in Lexington have crafted a mitigation strategy that includes a community land trust, which is intended to provide permanent protection for the low‐income community to be affected by the highway extension. Although the community land trust may be an attractive option for maintaining housing affordability and community cohesion, the idea must overcome some significant hurdles if it is going to be useful as an environmental impact mitigation tool. One problem is selling the idea of communal land ownership to African American and low‐income households. Part of the challenge is to design a method for sharing capital gains that gives an adequate return to home buyers while maintaining affordability. Another difficulty concerns renters who are eligible for only limited relocation subsidies that in many cases will not be enough to cover the cost of new rental housing.     

“THERE'S NO PLACE LIKE NEW ORLEANS”: SENSE OF PLACE AND COMMUNITY RECOVERY IN THE NINTH WARD AFTER HURRICANE KATRINA

ABSTRACT: This study contributes to the literature on the strength of place attachment, identity, and dependence in low‐ and moderate‐income neighborhoods. It also engages the literature concerning the role of sense of place in community engagement and the disruption in place attachment, identity, and dependence that natural disasters can cause. By drawing on interview data collected from residents who returned to New Orleans after the storm and from former New Orleanians who evacuated to Houston but did not return, this article investigates the “sense of place” that residents in Ninth Ward New Orleans neighborhoods identify in their narratives about their pre‐ and post‐Hurricane Katrina experiences. The data considered here suggest that returning residents believe that New Orleans in general (and their Ninth Ward neighborhoods in particular) possess a unique bundle of characteristics that, when taken together, cannot be found or replicated elsewhere. While sense of place is an important motivator for returning residents, the data also suggest that complementary factors must be in place if the full potential of this social resource is to be realized.     

Attracting Middle‐Income Families in the Hope VI Public Housing Revitalization Program

Abstract: While the growing literature on HOPE VI emphasizes the presumed benefits of income mixing these benefits are most likely to occur if middle‐income families with children are drawn to these sites. But is this feasible? Our comparative case study analysis of four HOPE VI sites in Cincinnati, Louisville, Baltimore, and Washington, DC, suggests that it will be difficult to achieve the mixing of lower‐ and middle‐income families with children. None of the four developments explicitly sought middle‐income families with children as part of their marketing. Louisville's HOPE VI site was the only one involving close collaboration between the school district, the housing authority, and city government from the beginning of the HOPE VI process. Moreover, the Louisville site was the only one successful in attracting middle‐income (and not simply subsidized moderate‐income) families with children. Strategies for making inner‐city HOPE VI sites more attractive for middle‐income families are discussed.