Showing papers on "Settlement (structural) published in 1977"

Subsidence above shallow tunnels in soft ground

Abstract: The paper investigates the influence of the depth of burial and crown settlement on the surface subsidence above shallow tunnels driven in soft ground Model tests were conducted on tunnels in sand and in clay, and these are compared with one another and with observations of settlements above some real tunnels There is good agreement between the model behavior and the field records The error, or normal probability curve, may be used as an approximation for the trough of surface subsidence, and the standard deviation is an appropriate measure of the width Empirical relationships exist between the depth of burial, the trough width and the crown and surface settlements for tunnels in sands and in clays

Settlement of refuse landfills

Abstract: The results of laboratory and field settlement studies of household refuse are presented and analyzed. A possible technique for stabilizing refuse landfills with the use of conventional grouting methods and a fly ash grout is discussed. Comparative results of settlement studies of both stabilized and unstabilized refuse are given. Using approaches similar to those utilized for natural soils, a settlement prediction technique is developed for refuse landfills and used with refuse behavioral parameters to make settlement predictions for a field loading situation. The predictions are then compared to the measured results and found to be reasonably comparable if parameters from field data are used.

Ovalization of cylindrical tanks as a result of foundation settlement

Abstract: A method of assessing the effect of foundation settlement upon the ovalization at the top of floating roof storage tanks is presented. The accuracy of the method is tested by comparison with field measurements and experiments on model tanks. Current design specifications for the permissible foundation settlement are reviewed and the extent to which they limit tank ovalization is assessed.

Estimating Foundation Settlements in Residual Soils

Abstract: Settlement of shallow foundations supported on residual soils derived from igneous and metamorphic rock may be estimated by using pressuremeter modulus, E p m data obtained from in-situ pressuremeter tests. A profile of E p m is developed when the test is performed in a continuous manner below a foundation element. The modulus data developed by this test accounts for variations in soil structure and compressibility since it is performed in situ. A linear relationship is indicated between the log of Standard Penetration Test N value and pressuremeter modulus E p m . The pressuremeter modulus, E p m , is also shown to approximate the soil modulus of deformation, E s . Pressuremeter modulus profiles developed below several proposed structures are used along with a simplified distribution of vertical strain to estimate expected building settlements. Actual settlement of foundation elements in these structures indicates good correlation. The method of settlement analysis is outlined and an illustrative example is included.

Settlement in sand-methods of calculating and factors affecting

Abstract: This paper tabulates methods of calculating settlement in sand and reviews fastors affecting the magnitude of the settlement. Because the methods give different answers it is necessary to always calculate settlement using several methods. Different methods such as the Terzaghi and Peck, Alan Modification, Meyerhof Modification and Peck Modification are described and discussed. It is concluded that the magnitude of settlement in sand as predicted by the available metheds vary considerably. The individual methods are not consistent in being either above or below average for varying soil conditions and foundation geometry. Lastly, engineering judgement is stressed in deriving the final settlement for each method, keeping in mind the factors affecting settlement and the published comparisons between predicted and observed settlement for various methods.

An Archaeological Survey on the Xoxocotlan Piedmont, Oaxaca, Mexico

Abstract: Surface survey on the piedmont near the present village of Xoxocotlan, Oaxaca, Mexico, has revealed the pattern of prehistoric settlement around an irrigation canal that distributed water from a dammed reservoir located on the flanks of Monte Alban. Intensive systematic collection techniques have permitted quantitative statements to be made about the density of occupation and the contribution of the irrigation system to the food supply of Monte Alban.

Sanitary landfill treatment, interstate highway 84

Abstract: A large quantity of refuse fill, including layers of earth cover, was transported in 1971 from a "town dump" to a new location, where it was placed and compacted in layers. Measurements were made of the volume decrease of the material. During the placing in the new location, nine settlement platforms were installed at various elevations and settlement readings taken frequently during the ensuing five years. These readings indicate that "primary" settlement was extremely rapid and "secondary" settlement has proceeded continuously, at rates that are comparable to those for peats. Samples of the material, when separated in the laboratory into their constituent parts, indicate that the fill was approximately 48% refuse material and 52% earth cover material, by volume.

The central place system of the Thessaly region of Greece

Abstract: The settlement system of Thessaly is examined within the framework provided by central place theory. The adoption of a systems approach to the research determines the organization of the work. Firstly, there is an analysis of the sectoral structure of the Greek economy with particular reference to retail trade. The importance of tertiary activity in the economy is indicated and the traditional nature of most Greek retailing is considered. Next, the physical, historical, economic and demographic background of Thessaly is described. The region consists of a fertile plain surrounded on all sides by mountains. The economy is dominated by agriculture and the secondary and tertiary sectors are strongly oriented to it. In the post-war period the population of the area has stagnated because of heavy rural emigration focussed primarily on Athens, The analysis of the settlement system then falls into three parts. The functional regions of Thessaly are identified by subjecting an interaction matrix of bus traffic flows to factor analysis. These describe the general structure of the settlement system and allow the subsequent detailed analysis of the settlement system of West Thessaly to be placed within a wider context. This detailed analysis is based primarily on data collected in the field. It consists of a study of the hierarchical and spatial structure of the system and the aggregate relationships between its components. A well developed hierarchical structure is found, and its historical evolution is examined. Following this, a study of consumer movements in West Thessaly is made which is based on data collected from questionnaires circulated in the region. The behaviour of the settlement system as revealed by this analysis accords closely with the structure of the system. A composite assessment of the settlement system is then made which relates its structure and behaviour to the theoretical framework of the research, and comparisons are made with other studies of settlement systems in-Greece. Finally, the Greek regional problem is examined, one element in which is the nature and role of the provincial settlement system, and the implications of this research for future planning strategies are outlined.

Analysis of ground surface settlement due to shallow shield tunnels

Abstract: When shallow tunnels are constructed under streets and buildings, surface settlement due to the tunnelling and its control becomes essential to prevent any environmental problems. This paper deals with finite element analysis and a simplified numerical method for computing the surface settlement due to tunnelling. The computed results are compared with the observations made during the construction of the shield tunnel through the diluvium deposit. The surface settlements due to the shield tunnel opening in the relatively shallow diluvium deposit are analyzed using the finite element method. The surface settlement computed from the elastic finite element analysis are added to the one from the empirical equation based on the lowering panel test. Non-linear finite element analysis was also carried out in order to account for the non-linearity of the soil. The analytical results are compared with the observed surface settlement obtained from the field measurement at the shield tunnelling site. In the sandy ground, it was noted that the elastic and plastic deformations occurred rapidly and that 95% of the final settlement was reached within 2 weeks. It was also noted that the non-linear finite element analysis using the hyperbolic representation of stress-strain relation gave a good estimate of the pattern of surface settlement. Finally, when only the final surface settlement due to the tunnel opening is required, it can be easily estimated from the summation of the elastic settlement and the settlement caused by local yielding.

The Physical Environment

Abstract: The valley is 12 km in length and is divided by a watershed at 550 m. from basins draining northwards to the Mesara Plain. The study area forms the southernmost part of the catchment, draining south, by the A. Kyriaki River, to the Libyan Sea. The river and several of its tributaries are ephemeral (Fig. 2).It is evident that the geology of the area dictates the shape of the land, and in the past, as now, controlled the quantity of flat land available for settlement and cultivation.

Estimation of pile group settlements

Abstract: In this paper attention is concentrated on solutions from elasticity theory and their application to practical problems. The basis of the analysis is described briefly and a number of parametric solutions are presented for the settlement ratio of pile groups. The determination of the soil parameters required to apply these solutions to practice is discussed and brief reference is made to a number of cases in which observed and theoretical pile group settlement behaviour have been compared. An illustrative example is given to demonstrate the use of the parametric solutions and the construction of design charts from the solutions are described with reference to a simple problem. /TRRL/

Restore method of differential settlement

Abstract: PURPOSE:A store tank which is constructed on a soft ground and unevenly subsided can be restored economically in a short period

Process for removing phosphorus contained in drain using gypsum

Abstract: PURPOSE:To provide a process for removing phosphours wherein gypsum is added to drain and dissolved to form a phosphide for settlement thereby making it possible to use inexpensive chemical agents and eliminate the need for such a complicated operation as adjusting pH of liquid to be treated

Waste water contained waste oil disposition method

Abstract: PURPOSE:To save consumption of subsidiary oil and perform efficient combastion disposal of iol contained in the waste water by combastion in using as fuel the free oil in the upper layer sedimented in a where the waste wter contained waste oil is kept for settlement.

Settlement method of storage tank

Abstract: PURPOSE:A settlement method of a storage tank, whereby the contact condition with sand can be detected without lifting a storage tank

Treatment process of organic waste water

Abstract: PURPOSE:To maintain continuous operation of the active sludge process by adding a specific chemical compound to the original waste water to suppress the rising (floating up) phenomenon of sludge in a settlement tank.