Browsing by Author "Sparks, A D W"

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    Aspects of planning civil engineering construction
    (1973) Los, Ronald Peter; Sparks, A D W
    The process of management is a continuous process of planning, organising, co-ordinating, motivating and controlling according to Pilcher. In any competitive construction organisation the objective of the managerd.al, staff is mainly to ensure that the firm's resources are utilised both effectively and efficiently. In this thesis certain aspects relating to the planning and control of a contractor's resources on a Civil Engineering contract are considered.
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    Aspects of tenders for construction contracts
    (1972) Crail, Hugh Francis; Sparks, A D W
    Before considering in detail that portion of the cost of a Civil Engineering project associated with the employment of a contractor, one should take an overall look at the total cost of an average project. This would usually include the following items a) cost of the land on which the project was to be built; b) legal expense incurred in drawing up conditions of contract, etc.; c) financial expense including interest on bank loans or the cost of issuing bonds; d) cost of construction itself; e) cost of employing consulting eng1neers to design and supervise the project; f) loss of interest that could be earned by capital tied up during the construction period; g) contingencies. It is clear that while construction costs do not constitute the complete cost of a project, they nevertheless form a very large part. Hence, once the consultants have been appointed, they theoretically expend a great deal of time and energy in choosing an optimal design in close co-operation with the promoter.
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    Aspects of the drainage process in soils
    (1986) Wardle, Gavin Roger; Sparks, A D W
    The initial portion of this thesis contains a review of basic theory. An experimental programme was also undertaken to measure soil parameters; and to observe heads and seepage rates during transient flow conditions in experiments. These experimental values were compared with results from finite element calculations. It was necessary for the candidate to devise a system for modifying an existing main-frame finite element package (ADINAT) in order to cope with the transient partly saturated draining state which exists above a falling water table. Good agreement was found between observed and computed transient heads. The experimental work of other investigators was also analysed by using this Finite Element program, and again good agreement was found between observed and computed transient conditions. It was decided in conjunction with the supervisor to limit this thesis to two-dimensional flow in the vertical plane.
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    The bearing capacity and settlement of gravel piles in clay
    (1980) Jones, David Leonard; Sparks, A D W
    The writer has been interested in the subject of gravel piles for a number of years and has been suprised at the lack of rational design methods. When the piles are inserted in sand their purpose is mainly one of densification and their effectiveness is usually measured by a Dutch Cone Penetrometer with an increase in cone resistance as the sand is densified. For clays the above method is clearly not applicable and a conservative approach has generally been adopted with regard to the pile length and spacing. There appears to be only one paper which is often quoted as a design method (Hughes and Withers 1974) and at least one contractor used this method as a basis for design (Cementation •1977). The State of the Art was advanced in .1976 when a symposium on ground treatment was held. Again the basic design philosophy adopted was that of Hughes and Withers, and numerous case histories appeared to back up the design approach. The writer was therefore interested in formulating a new design method which could act as a check on the traditional method. Also, it was felt that an understanding of the stress-strain behaviour of the pile was needed to fully appreciate the implications of any design method. However, prior to the submission of the thesis the writer was made aware of work undertaken in Australia (Balaam and Booker 1979) which used elastic methods to establish the stress-strain behaviour of a pile. This approach is valuable as the sensitivity of design to various parameter changes can quickly be checked by reference to the numerous graphs presented. As this work is little known the relevant graphs have been reproduced in Ch. 8 of this thesis. It is intended that this thesis will act as a concise guide to column behaviour and design, as well as to the uses to which they may be put. Also, a new design method is proposed which. has been developed from a basic understanding of the stress-strain behaviour of a pile. The sequential approach used in developing this thesis is outlined in the next section.
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    Comparison of hydrological and groundwater design methods
    (1980) Rossouw, Brian Terrence Adrian; Sparks, A D W
    One of the objectives in this thesis is to provide a handbook on groundwater hydrology for the practical engineer. A handbook should be a useful and dependable servant to its owner and user. In order to fill this role, handbooks in different fields must differ in accordance with the degree of complexity of the material systems involved and the extent - from qualitative to quantitative - to which fundamental parameters have been recognised, defined, and built into .dependable theoretical solutions. A handbook on engineering drainage must firstly, provide an understanding of the approach and reasons for determining the nature of run-off from any particular catchment whether it be a river catchment or a surfaced pavement of relatively small surface area. Then, secondly, the handbook must provide reliable methods for determining the amount of run-off that would result from a particular catchment. There are a number of methods which can be used to produce the desired results and an effort is made herein to present those methods, presently used in Southern Africa, as clearly as possible. It is accepted that computers are being used more often for drainage calculations, and that a seemingly precise solution appears with relatively little input effort. The work contained herein is a plea to engineers to return to the basics in order to understand the complexity of drainage determinations and to achieve what the author terms "the feel for drainage" - i.e. the knowledge of when to accept a result and when to advocate an amendment to the solution. This results not only in the most practical solution but also possibly the most economical. The final solution is influenced by both the structure involved and the skill of the associated worker. is a very real danger of the engineer's sense of judgement being lost by the over application of the computer.
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    The determination of road sections by computer for use in road design
    (1974) Keuck, Gerhard Helmut Max; Sparks, A D W
    A brief resume of ,recent developments in the design of roads is given with special reference to the increasing part played by automated methods by means of which higher degrees of optimization may be achieved. Flow charts illustrating road design demonstrate the relative importance of the determination of the transverse road section by computer. The finished transverse road section, called a template, consists of a central portion and the outer sloped cut and fill banks. The central portion covers the carriageway(s) and shoulders, the shape of which is predetermined by the geometric .design of the road surface and is independent of ground shape. The outer sloped banks, called the side-drain template, are dependent upon the position of the ground surface in relation to the predetermined central portion. When a road is to be built, the road authority usually prescribes the final transverse shape of the road by specifying a standard road template. At every point along the road a specific template can then be determined in accordance with the standard template. However, problems are experienced because certain available computer programs are unable to execute the side-drain portion of the standard road template correctly while earthwork quantities are being calculated. Several available programs are investigated with regard to the procedures adopted by them for the selection of appropriate road side-drain templates. Deficiencies in these programs are noted. A general solution to the problem of the logical determination of road sections by computer, namely, the method of the locus of the slope stake point, is introduced and elucidated. The success of the method is confirmed by the presentation of the completely operative computer program SHARM for the calculation of road earthworks quantities: The use of the program is demonstrated by a short sample run. Limitations of the method of the locus of the slope stake point and of the SHARM program are noted, and finally some future developments are discussed.
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    Expansive and collapsing behaviour of volume change soils
    (1990) De Sousa Vinagre, Tiberio J V; De Sousa Vinagre, Tiberio J V; Sparks, A D W; Sparks, A D W
    This thesis is designed to achieve three goals: Goal One - to introduce the reader to soils exhibiting expansive and/or collapsing behaviour; Goal Two - to provide an in depth understanding of aspects of this behaviour, obtained from an extensive study of these soil types; and, Goal Three - to serve as a reference for future research work (a recommendation for further research proposed in Chapter Ten of this thesis). The thesis is divided in two main parts. In the first part representative soil types were selected on the basis of their properties and expected engineering behaviour. The soil structure and clay minerals were also studied in part one of this thesis. The second part of the thesis deals with aspects of expansive and collapsing behaviour of soils. Chapter three provides the introduction to the subsequent chapters on expansive and collapsing behaviour of volume change soils.
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    Finite element analysis of groundwater contamination
    (1990) Mahomed, N; Sparks, A D W
    The purpose of this study was to develop a computational Finite Element model, validated by experimentation, to assist in the understanding of groundwater contamination problems. It was mainly aimed at studying the extent and manner of travel of contaminants in the saturated soil of unconfined aquifers which may be pumped by of wells.
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    Stress paths and collapsing soils
    (1977) Errera, Leonardo Arthur; Sparks, A D W
    The design of footings and the accurate prediction of settlements is inherently difficult as the parameters involved vary considerably. The initial stage of the design consists of three steps. The first step is to define all the parameters required. The second step is to give quantitive values to these parameters by performing tests and calculations. The third and last step should be the investigation of changes in external or local conditions on these parameters. The importance of this step is brought to the fore when considering collapsing soils and heaving clays. The next stage of the design would be to consider the stress changes at either an average point or a grid of points below the footing within the soil mass. To do this the engineer makes use of conventional methods of analysis. Factors such as horizontal strata and variations of properties with depth must be considered. Once the engineer has defined all the stress changes he must then decide which method of settlement prediction would be appropriate. The deformations of the soil mass do not only depend on the change in stress, but also on the previous stress-strain history of the soil and the actual variation of stresses with time during the settlement process. (e.g. see the error involved when considering the Skempton-Bjerrum method. Refer to Chapter 7). As the stress path accurately reflects all the stress changes the stress path method is an excellent tool for describing the stress and strain variations. There are numerous methods all of which have their merits and disadvantages. These will be discussed, and the influence of the stress path on settlement prediction is also analysed. Although a stress path method of settlement prediction might not always be essential, an analysis of a typical stress path for the particular problem would appear to be an excellent initial approach to deciding on the validity of any method of settlement prediction. The final stage is the accumulation of data and the prediction of the settlement value using one or more of the following methods: 1) Find the field penetration using the Dutch Cone Penetrometer {or any accepted penetrometer). This value is then used in conjunction with predetermined design curves to find the settlement. 2) Make use of settlement formulae which are directly derived from elastic theory. These do not take into consideration any of the variations of properties within the soil mass (see Chapter 7). 3) Define an average point or a number of grid points below the foundation (see Chapter 5). For each point evaluate a stress variation and hence calculate a corresponding strain value. The settlement of the footing is then calculated using the strain values. The above estimated settlement values are also to be regarded with caution, as foundation size and rigidity do influence predicted values. There are however methods to diminish these inaccuracies (see Chapters 3 and 7). The engineer should be able to predict the stress variations with reasonable accuracy if he has a knowledge of the influences of all these factors on the idealised elastic case (e.g. foundation size, rigidity, existing horizontal stresses etc.). It therefore becomes apparent that the predicted settlement is not a 'wild estimate', but a carefully analysed value which can be forecast with confidence, providing the proper tests have been made.
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    Transient flow of water in saturated-unsaturated soil profiles
    (1990) Ketteringham, Wayne Stuart; Sparks, A D W
    In this thesis tile transient flow of water, during tile drainage process in saturated-unsaturated soil profiles, was studied. Drainage experiments were performed on two different soil profiles. The first experiment undertaken was tile drainage of a vertical column of sand. This experiment was performed on two sands of differing grain size and grading. The second experiment undertaken was the drainage towards a well from a wedge of sand (cake slice) using yet a different coarse sand.