Heiman, JL, Bakoss, SL, Burfitt, AJ & Cridland, L 1980, 'MEASURED AND PREDICTED AXIAL STRAINS AND DEFORMATIONS IN A COLUMN OF A TALL REINFORCED CONCRETE BUILDING.', Institution of Engineers, Australia, Civil Engineering Transactions, vol. CE22, no. 3, pp. 193-201.
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A site investigation was carried out to determine the axial deformations of a column in a tall reinforced concrete building. Strains were measured in the column concrete using vibrating wire gages and the column deformations were measured by precise leveling. In addition to strain measurements on standard laboratory shrinkage and creep specimens, strain data were obtained from tests that related more closely to the site conditions. Appreciable differences occurred between shrinkage and creep strains measured in the laboratory and some of those obtained by methods given in codes. Shortcomings were found in some of the equations used to predict long-term creep strains from laboratory data and a hyperbolic equation was developed that enabled more accurate predictions to be made. Measured strains in the column were compared with predicted values obtained by two calculation methods and good agreement was obtained.
LOGANATHAN, P & BALAKRISHNAMURTI, TS 1980, 'EFFECTS OF NPK FERTILIZERS ON YOUNG COCONUT (COCOS-NUCIFERA) ON A SANDY SOIL IN SRI-LANKA', EXPERIMENTAL AGRICULTURE, vol. 16, no. 1, pp. 41-48.
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In a 4 × 4 × 4 NPK field experiment with coconut on a sandy soil, N increased girth, height and leaf production during the pre-bearing period, but phosphorus (up to 6½ years) and K (up to 3½ years) had no effect on any vegetative growth parameters. The rates of fertilizers for optimum copra and nut yield (13 to 16 years) were 0.35, 0.73 and 0.64 kg N, PO and KO/palm/ year respectively. The high P requirement was due to the low solubility of the saphos phosphate in these sandy soils. A positive N × P interaction was also observed. © 1980, Cambridge University Press. All rights reserved.
LOGANATHAN, P & FERNANDO, WT 1980, 'PHOSPHORUS SORPTION BY SOME COCONUT-GROWING ACID SOILS OF SRI-LANKA AND ITS RELATIONSHIP TO SELECTED SOIL PROPERTIES', JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, vol. 31, no. 7, pp. 709-717.
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Phosphorus (P) sorption in the presence of 10−2M calcium chloride by ten coconut‐growing acid soil samples of Sri Lanka belonging to the Ultisol, Alfisol and Entisol orders was evaluated using the Langmuir sorption isotherm. The data for all samples fitted the single‐site Langmuir sorption isotherm when equilibrium P was less than 1 μg ml−1, but showed some deviations at larger concentrations of P. A two‐site Langmuir sorption isotherm was successfully used to describe the sorption data of three samples at these high concentrations. The single‐site Langmuir sorption maxima were greater for Ultisols (349–825 μg g−1) than for the other soils (136–345 μg g−1). These sorption maxima were significantly correlated with %‐clay, %‐silt, dithionite‐extractable iron, and 1M ammonium acetate (pH 4.8)‐extractable aluminium. Regression analysis of P sorption on different forms of iron (Fe) and aluminium (Al) indicated that crystalline ‘free Fe oxides’ (dithionite‐extractable Fe minus 0.3M oxalate‐extractable Fe) and ‘active Al’ which consists of hydroxy Al monomers and polymers [1M ammonium acetates, (pH 4.8)‐extractable Al minus 1M potassium chloride extractable Al] were the important factors contributing towards P sorption. Copyright © 1980 John Wiley & Sons, Ltd
Phuoc, HB & Tanner, RI 1980, 'Thermally-induced extrudate swell', Journal of Fluid Mechanics, vol. 98, no. 2, pp. 253-271.
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In many polymer processing applications, the generation of heat by viscous losses in the flowing molten polymer is highly significant. The heating reduces the viscosity of the melt sharply and the flow patterns are different from the isothermal case. In this paper, a finite element scheme based on the Galerkin method is developed and is used to explore the effects of thermally induced property changes in extrusion.In the program we solve simultaneously for the flow and temperature fields at each iteration. To check the program for accuracy and correctness, some simple problems were first attempted. A solution for viscous heating in Poiseuille flow was used to check the variable-viscosity part of the program. The crucial convection (‘radiation’) boundary condition was checked using the solution for cooling of a moving rod. Finally, the swelling of extruded jets with self-heating was investigated. A new phenomenon, thermal extrudate swell, was thereby discovered. We have found extrudate expansions up to 70% of the die diameter in a Newtonian fluid with thermal properties similar to those of low density polyethylene. It is clear that this phenomenon will affect many experimental interpretations of extrudate swelling.
