Design considerations for mine workings under accumulations of water

The study outlines the effects of surface and underground subsidence patterns on the spatial distribution of in-situ permeability and its effects on groundwater inflow. The behaviour of strata surrounding a longwall face where limited knowledge exists has been outlined. The effects of mining subsidence on the surface flow pattern have been described with the remedial solutions. The mechanism of formation of sinkholes in certain chemical rockmass has been described. Factors affecting mine water inflow have been described in detail with the aid of a simplified conceptual model and case studies. Practical examples of undersea workings and those under a large accumulation of water are given, both in the United Kingdom and worldwide.     

Experience of Using Energy Effects in Ore Preparation and Concentration of Ferruginous Quartzites

The possibility is considered for changing the physico-mechanical and technological properties of ferruginous quartzites of the Mikhailovsk deposit by means of dosed energy actions.     

Prediction of High Methane-Recovery Regions and Gas Extraction Technology Based on Geodynamic Zoning of Bowels

An analysis is performed for the existing hypotheses and theories used for calculating the technological parameters of operations on methane extraction from coal seams. The priority of geodynamic processes in methane collector formation, as well as the methods applied for the morphometry and processing of the remote probing data are substantiated. The urgency is shown for the investigation into the autooxidation and other exothermic reactions proceeding in coal seams and leading to methane transition to the free state.     

The 20th century whole-basin trophic history of an inter-drumlin lake in an agricultural catchment

Eight 1-m sediment cores were extracted from across the basin of Friary Lough, a 5.4-ha eutrophic lake in a wholly grassland agricultural catchment in Co. Tyrone, Northern Ireland. Sedimentary TP, diatom inferred TP, Ca, Na, Fe, Mn, loss-on-ignition (LOI), dry weight and density were determined in the core profiles. Core dating and correlation gave a 210Pb, 137Cs and 241Am chronology from 1906 to 1995 and enabled a whole-basin estimate of chemical and sediment accumulation rate over the 20th Century. The major changes for all parameters occurred after c. 1946. Sediment accumulation rate was most influenced by organic matter accumulations, probably of planktonic origin, and increasing after c. 1946. Inorganic sediment accumulation rate was found to be largely unchanging through the century at 10 t km(-2) yr(-1) when expressed as catchment exports. All chemical accumulation rate changes occurred after c. 1946. Total phosphorus accumulation rate, however, was found to be the only chemical to be increasing throughout the epilimnion and hypolimnion areas of the sedimentary basin at an average of 22.5 mg m(-2) yr(-1) between 1946 and 1995. The other chemical parameters showed increasing accumulation rates after c. 1946 in the epilimnion part of the basin only. Interpreted in terms of whole-basin sedimentation and catchment export processes over time, it is suggested that diffuse TP inputs are independent of sediment inputs. This corresponds to hydrochemical models that suggest soluble P as the primary fraction that is lost from grassland catchments. The increase in sedimentary TP accumulation rate, and DI-TP concentration, are also explained with regard to current models that suggest increases in runoff P concentrations from elevated soil P concentrations. Increases in eplimnion chemical and sediment accumulation rate after c. 1946 may be due to local erosion that has limited impact on lake basin sedimentation.     

Finite element modelling of plate girders with web openings

This paper is concerned with a finite element model to predict the behaviour and ultimate load of plate girders with web openings. The finite element package is used to model the plate girders with web openings. Accuracy of the model is assessed by applying it to plate girders tested earlier by other researchers. Comparison of analytical results with the available experimental results for yielding patterns, ultimate load values and load–deflection relationships show good agreement between the finite element and experimental results thus validating the accuracy of the proposed model. The proposed finite element method was extended to carry out a parametric study. The study covered parameters such as web slenderness and flange stiffness.     

Contribution à l'étude de la détermination des conditions de formation des haloformes

In recent years the presence of haloforms has been observed by some researchers in waters of various origins.The aim of this study is to determine the conditions in which chloroform is formed by chlorination of aqueous solutions of some organic compounds.The first part of this work was carried out by chlorination of synthetic basic solutions of acetone and thus enabled us to determine the reagent concentrations needed to obtain the maximum quantity of chloroform.We studied next the effect of chlorination on organic material solutions (humic acids and phenols), in the course of an oxidation treatment; the results obtained by chlorination of aqueous solutions of humic substances show that the quantity of chloroform produced passes through a maximum value which depends on the time of ozonisation. Similar results were obtained for the chlorination of phenol solutions during oxidation by the u.v. + H₂O₂ system. These results may be explained by the partial degradation of the molecules which leads in the formation of reactional intermediate precursors of the haloform reaction. We undertook at the same time the study of a rapid test allowing us to detect the presence of haloform reaction precursors in a certain sample of water.     

Settlements and deformations of industrial structure built on weak soils

Conclusions 1. In engineering-geologic explorations, it is necessary to investigate the engineering-geologic morphology to a depth of 15–18 m: lenses and interlayers of weak soils - unevenly compacted silty-sand fills, peat, slime, etc.2. Open unwatering of pits in the vicinity (10–15 m) of existing structures is impermissible, since it leads to removal of fine soil fractions because of piping, and to large and impermissible deformations of the load-bearing elements of the structures. In such cases, deep groundwater lowering by means of wellpoints should be used.In the case described in this article, the industrial structure underwent a mean settlement of about 20 cm, a tilt of 0.015, and a wall deflection of 0.002. By using deep groundwater lowering, such deformations could have been prevented.3. The development of settlements with time was due to the presence of weak soils - peat lenses and thin slime interlayers - in the foundation bed of the shop.4. An effective means for stopping the settlement of the industrial structure was the construction, under the walls, of two rows of cast-in-place piles with cantilever beams to which the wall loads were transmitted.Scientific-Research Institute of Foundations. GIPROLESKhIM. Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 1, pp. 5–7, January–February, 1975.