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Durham E-Theses Soil creep: an assessment of certain controlling factors with special reference to upper Weardale England Anderson, E. W. How to cite: Anderson, E. W. (1977) Soil creep: an assessment of certain controlling factors with special reference to upper Weardale England, Durham theses, Durham University. Available at Durham E-Theses Online: http://etheses.dur.ac.uk/8394/ Use policy The full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that: • a full bibliographic reference is made to the original source • a link is made to the metadata record in Durham E-Theses • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders. Please consult the full Durham E-Theses policy for further details. Academic Support Oce, Durham University, University Oce, Old Elvet, Durham DH1 3HP e-mail: [email protected] Tel: +44 0191 334 6107 http://etheses.dur.ac.uk 2 SOIL. CREEP; AN ASSESSMENT. OP CERTAIN CONTROLLING FACTORS WITH SPECIAL REFERENCE TO UPPER WEARMLE. ENGLAND by E.W. ANDERSON M.A. (Oxon) M.A. (Manch) Part-time research student in the Department of Geography, University of Durham The copyright of this thesis rests with the author. No quotation from it should be published without his prior written consent and information derived from it should be acknowledged. A thesis submitted to the University of Durham for the degree of Doctor of Philosophy JANUARY 1977 ABSTRACT Soil creep is important as a process affecting landforra development, as a factor influencing slope stability and as an element of land wastage. Few definitive studies have been made of th.e process and work on variables controlling rates of soil creep is very limited. Therefore, in the present study it was decided to monitor creep with a number of devices over different lengths of time so that variability over space and time could be determined. This involved investigations on three distinct scales: those of the laboratory, the plot and the drainage basin. To measure rates of creep and to monitor probable controlling variables, new instruments were designed and established procedures were modified. All new instruments were validated and essential features at each stage of the work were replication and the measurement of "local variability. After initial tests on experimental plots a drainage basin was selected and instrumented for the pilot study, in which both creep rates and a number of basin variables were investigated. The experimental.design for the main study was then constructed, using six main instruments: Anderson's Inclinometer, Anderson's Tubes, aluminium pillars, dowelling pillars, loung's Pits, and Cassidy's Tubes to monitor rates of creep on each of twenty measuring plots. The basin factors considered as probable controls were categorised, as: (a) external or meteorological (b) surface, including slope angle and vegetation (c) internal, comprising the main soil variables Annual rates of creep, shown to vary from'0.3Dim to 2.4nmi, were correlated with eighteen major basin factors. The results of graphical and statistical analysis showed that rates of creep are controlled by a number of 'force' factors, chiefly soil moisture, field capacity and plasticity index, together with 'resistance' factors, particularly bulk density and a number of shear stress measures. , The importance of moisture and its related variables was reinforced by principal component analysis and confirmed in a model produced by stepwise multiple regression. Laboratory experiments with soil troughs demonstrated the relationship between soil movement and meteorological cycles. The daily monitoring of creep for extended periods on an experimental plot allowed short term movement to be assessed. Further developments indicated by these results include long term monitoring and the mapping of spatial variation of creep over a 'landscape' using the key variables identified. ACKNOWLEDGMENTS I should like to acknowledge the assistance of the following: Professor W.B. Fisher for accepting me as a research student. Dr. P. Beaumont, my supervisor, for all his helpful comment and meticulous scrutiny of the written work. Mr. N.J. Cox for many interesting discussions and valuable help with organising the computer analysis. Dr. J.R. Jennings for running certain of the computer programs, Mr. R. Snaith of the Weardale Lead Company, for the use of his meteorological data. Mr. J, Bumby and the boys of the Castle School, Stanhope, for the use of their meteorological readings. Various Companies, including J.M.A. Scientific, Spillers, Engineering Laboratories and Ashworths for checking instruments in their laboratories. My friends in Rookhope village for their cheerfulness and interest during my 120 visits to the village. My wife and three sons for their forbearance. My Mother for all her work in typing the study and as sometime field assistant, but particularly for her encouragement. When everything is moving at once, nothing appears to be moving Nature constantly begins the same things over again, years, days, hours, spaces too. And numbers run end to end, one after another. This makes something in a way infinite and eternal PASCAL: Pensees TABLE OF CONTENTS Chapter Page 1 BACKGROUND TO THE STUDY 1 1.1. Introductory 1.2. The Model Approach 1.3. Examples of Models 1.4. The Measurement of Mass Movement 1.5. Soil Creep 1.6. Mechanism of Soil Creep 1.7. Possible Variables controlling Soil Creep 1.8. Aims of the Study 2. TECHNIQUES FOR MEASURING SOIL CREEP 27 2.1. Classification of Techniques 2.2. Instruments which measure extremely accurately 2.2.1. General 2*2,2. The S.G.I. Rod Inclinometer 2.2.3. Linear Motion Transducers 2.2.4. Strain Gauges 2.2.5. Strain Gauge Inclinometer 2.2*6. Finlayson's Helix Tube 2.2.7. Discussion 2.3. Instruments which measure in the long term 2.3.1. General 2.3.2. Pillars 2.3.3. Bore Holes 2.3.4. Cassidy's Tubes 2.3.5. Hydrofluoric Acid Cylinders 2.3.6. Young's Pits ! 2.3.7. Selby's Cones 2.3.8. Painted Rocks or Markers 2.3.9. Vegetation 2.3.10. Discussion 2.4. Instruments which magnify and measure the changes 2.4.1. General Chapter page 2 contd. 2.4.2. Kirkby's 'T' Pegs 2.4.3. Evans' 'T' Bar 2.4.4. Discussion 2.5>. Conclusions 3 INSTRUMENT SELECTION 65 3.1. Introductory 3.2. The Anderson Inclinometer 3.2.1. The Instrument 3.2.2. Procedure 3.2.3. Analysis 3.2.4. Advantages 3.2.5. Pegs 3.2.6. Peg Insertion 3.2.7. Validation 3.2.8. Discussion 3.3. The Anderson Tube 3.3.1. The Instrument 3.3.2. Procedure 3.3.3. Analysis 3.3.4. Advantages and Limitations 3.3.5. Modifications 3.3.6. Validation 3.3.7. Discussion 3.4. Other Instruments 3.4.1. Young's Pits 3.4.2. Aluminium Pillars 3.4.3. Cassidy's Tubes 3.4.4. Dowelling Pillars 3.4.5- Sand Pillars 3.4.6. Open Tubes 3.4.7. Discussion 4 TECHNIQUES FOR MEASURING BASIN FACTORS AT 98 ROOKHOPE 4.1. Introductory 4.2. External Factors 4.3. Surface Factors Chapter Page 4 contd. 4.3.1. Location 4.3.2. Slope 4.3.3. Vegetation 4.4. Internal Factors 4.4.1. Soil Moisture 4.4.2. Field Capacity 4.4.3. Linear Shrinkage 4.4.4. Plastic Limit 4.4.5'. Liquid Limit 4.4.6. Organic Matter 4.4.7. Soil Depth 4.4.8. Saturation Level 4.4.9. Bulk Density 4.4.10. Shear Strength 4.4.11. Texture 4.4.12. Root Factors LABORATORY PROGRAMBffi 125 5.1. Introductory 5.2, The Soil Troughs and Measuring Instruments 5.3, Programme 5.3.1. Experiment 1 5.3.2. Experiment 2 5.3.3. Experiment 3 5.3.4. Experiment 4 5.3.5. Experiment 5 5.4. Summary SUPPORTING RESEARCH SITES 163 6.1. Introductory 6.2. Etherow Valley 6.2.1. Background 6.2.2. Programme 6.2.3. Results 6.3. Bidston Hill 6.3.1. Background 6.3.2. Programme 6.3.3. Results Chapter Page 6 contd. 6;-.4. M53 Motorway 6.4.1. Background 6.4.2. Programme 6.4.3. Results 6.5. North Wales 6.5.1. Background 6.5.2. Programme 6.5.3. Results 6.6. Discussion 6.7. Durham City Area 6.7.1. Background 6.1.2. Programme 6.7.3. Results 6.8. Summar;^- SELECTION OF THE MAIN EXPERIMENTAL AREA 225 7.1. Introductory 7.2. Stage 1 7.3. Stage 2 7.4. Stage 5 8 BACKGROUND TO UPPER WEARDALE AND THE BASIN 234 AT ROOKHOPE 8.1. Introductory 8.2. Geology 8.3. Geomorphological Development 8.4. Soils 8.5. Climate 8.6. Vegetation 8.7. Rookhope Basin INSTRUMENTATION OP ROOKHOPE BASIN 273 9.1. Introductory 9.2. Pilot Programme 9.3. Main Study Programme 9.4. Procedure 9.5. Plot Disposition Chapter Page 10 THE PILOT STUDY AND SUPPLEMENTARY WORK 296 AT ROOKHOPE 10.1 Introductory fO.2 Pilot Study 10*2.1. Basin 1 10.2.2. Basin 2 10.2.3. Basin Outlet Plots 10.2.4. The Transect 10.3'. Discussion 10.4 Supplementary Studies 10.4.1. Transects 10.4.2. Flange Pegs 10.4.3. Sectional Tubes 10.4.4. Excavated Plots 10.4.5. Summary 10.5 Boundary Transects 10.6 Open Tubes and Steel Rods 10.7 Control Pegs 10.8 Peg Settlement Time 10.9 Summary 11 RATES OF SOIL CREEP 317 1.1 Introductory 1.2 Measurementt^Biates 1.3 Results 1.4 Bodily Movement 1.5 Maximum Depth of Movement 1.6 .Volumetric Rates of Creep 1.7 Comparison with other Results 1.8 Instrument Comparison 12 BASIN FACTORS 371 12.1 Introductory 12.2 External Factors Chapter page 12 contd.