The deformation mechanics of rubble masonry concrete (RMC) are explored experimentally and theoretically with reference to the behaviours of analogous concrete and natural conglomerate. The composite stiffness of large RMC cubic specimens, containing rock types exhibiting diametrically extreme values of stiffness, was determined dynamically and measured statically to gain a preliminary indication of the range of values likely to be encountered. A broad spectrum of moduli of deformation and Poisson's ratios were recorded.
Effects of particle size distribution (PSD) of ground granulated blastfurnace slag (GGBS) on some durability properties (as defined by intrinsic oxygen permeability, total porosity and pore size distribution) of slag cement mortars. The PSD of CCBS was represented by the parameters of Rosin-Rammler (R-R) distribution function, namely position parameter x, and slope n. The results showed that oxygen permeability and total porosity of the mortar mixes studied increased with increases in water-cement ratios whatever the age at which the specimens were tested and irrespective of percentage of slag in the mixes.
This paper is based on investigative work seeking to explicitly link the different skills levels of fabricators erecting steel frames to the amount of column out-of-plumbs they induce. Stability factors can then be chosen at the frame design stage and linked to different out-of-plumb tolerances depending on the skills available or anticipated from steel fabricators and erectors. A survey of column out-of-plumbs was carried out on nine structures around the Johannesburg area, ranging from simple portal frame parking bays built by contractors with an informal sector type of constructional skill to executive office complexes built by contractors with established constructional track records. Tests were also carried out on laboratory-size portal frames to establish the equivalent induced lateral forces due to initial column out-of-plumb.
The objective of this paper is to investigate and quantify the resilient behaviour of the ballast pavement layer by means of dynamic triaxial testing. Factors affecting dynamic triaxial testing on granular material were analysed by means of a literature study and are summarized for convenience. The maximum principal stress difference and the degree of fouling were varied during the triaxial tests. Relationships for the prediction of the resilient modulus are presented.
This paper gives an overview of human settlement developments as related to sustainable development. Findings of various studies on waste management in the city of Dar es Salaam are reported. Both liquid and solid waste management as important measures of sustainable development are discussed, as are urbanization trends in Tanzania and Dar es Salaam city in particular. The paper is based on recent studies on liquid and solid waste management, and findings related to human settlements and environmental management in the city of Dar es Salaam.
Practical design and construction considerations, other than detailed specifications, were discussed with reference to precedent, experimental testing and theoretical modelling. Consideration of several failure mechanisms indicated that the RMC arch problem is primarily one of equilibrium rather than of material strength and that structural stability without reinforcing can be ensured.
This paper descriptionbes model experiments carried out by the writer at Loskop Dam during 1936, resulting in the design of the device (hereafter called a ""splitter"") now incorporated in that dam and in the Vaal bank Dam.