The behaviour of semi arid residual soils derived from the weathering of Johannesburg quartzite are difficult to predict because of their heterogeneous particle constitution and weakly bonded structure. The collapse behaviour of undisturbed and remoulded weathered Johannesburg quartzite was investigated; and the reliability of the collapse settlement data was also evaluated. The results showed ...

Methods to improve bearing capacity of footing resting of collapsing soil can, in fact, take two approaches, improving soil strength properties and intrusion of reinforcing sorces into soil. The footing is modeled by a square steel plate 0.1 by 0.1 m. The footing is loaded as to have a stress of 40 kPa and settlement is receded in dry and in soaking conditions. Two depths of the geo-mesh reinfo...

in the first impounding of rockfill dams, additional settlements occur in upstream side in saturated rockfills due to collapse phenomenon even high rainy seasons can cause additional deformation in the dumped rockfills. unfortunately these displacements are not taken into account in the conventional numerical models which are currently used to predict embankment dam behavior during impounding. ...

We examined the effects of fire disturbance on permafrost degradation and thaw settlement across a series of wildfires (from ~1930 to 2010) in the forested areas of collapse-scar bog complexes in the Tanana Flats lowland of interior Alaska. Field measurements were combined with numerical modeling of soil thermal dynamics to assess the roles of fire severity and climate history in postfire perma...

Expansive and collapsible soils are some of the most widely distributed and costly of geologic hazards. These soils are subject to changes in volume and settlement in response to wetting and drying, often resulting in severe damage to structures. Collapsing soils are generally characterized by sudden and large volume decrease at constant stress when inundated with water. A geotechnical engineer...

Serial roentgenograms of 40 patients who had 70 cervical intervertebral spaces grafted with ethylene oxide sterilized cadaver bone and 28 patients who received 44 iliac crest auto grafts for anterior cervical spine fusion, were studied. The radiological evaluation was made on the basis of settlement of intervertebral spaces, fusion rate, delayed union, non-union, graft collapse and extrusion of...

The Caucasus has seen numerous crises since the region gained independence following the collapse of the Soviet Union. Some of these crises have not been resolved yet as evidenced by recent Russia-Georgia conflict. This paper seeks to analyze such crises within the framework of significant geopolitical changes unfolded by the collapse of the Soviet Union. The author argues that in the post-Sovi...

This paper presents 2,000 years of settlement and land use within the Lake Pátzcuaro Basin, Mexico. Three findings challenge the conclusions of previous research. We show (i) that initial land degradation was caused by settlement, not by agriculture; (ii) that population density inversely correlates with erosion; and (iii) that land degradation was associated with European Conquest but not from...

Tunnelling through cities underlain by soft soil, commonly associated with soil movement around the tunnels and subsequent surface settlement. The predication of ground movement during the tunnelling and optimum support pressure could be based on analytical, empirical or the numerical methods. The commonly used Earth pressure balance (EPB) tunneling machines, uses the excavated soil in a pressu...

Changing economies and patterns of trade, rather than climatic deterioration, could have critically marginalized the Norse Greenland settlements and effectively sealed their fate. Counter-intuitively, the end of Norse Greenland might not be symptomatic of a failure to adapt to environmental change, but a consequence of successful wider economic developments of Norse communities across North Atl...