Joernaal van die Suid-Afrikaanse Instituut van Siviele Ingenieurswese
Academy of Science of South Africa
About: Joernaal van die Suid-Afrikaanse Instituut van Siviele Ingenieurswese is an academic journal published by Academy of Science of South Africa. The journal publishes majorly in the area(s): Durability & Engineering. It has an ISSN identifier of 1021-2019. It is also open access. Over the lifetime, 189 publications have been published receiving 1283 citations. The journal is also known as: Joernaal van die Suid-Afrikaanse Instituut van Siviele Ingenieurs.
Papers published on a yearly basis
TL;DR: A semi-mechanistic, semi-empirical analysis technique has been developed in South Africa in terms of which deflection bowl parameters, measured with the falling weight deflectometer, are used in a relative benchmarking methodology in conjunction with standardised visual survey methodology to give guidance on individual layer strengths and pinpoint rehabilitation needs.
Abstract: The falling weight deflectometer (FWD) is used worldwide as an established, valuable, nondestructive road testing device for pavement structural analyses. The FWD is used mostly for rehabilitation project level design investigations and for pavement management system (PMS) monitoring on a network basis. In project level investigations, design charts based on both empirical relations and mechanistic or theoretically based approaches are often used to provide structural evaluations and rehabilitation options. The full mechanistic approach normally uses multi-layer linear elastic theory and back-calculation procedures that have come under scrutiny owing to the inaccuracy of results. A semi-mechanistic, semi-empirical analysis technique has been developed in South Africa in terms of which deflection bowl parameters, measured with the FWD, are used in a relative benchmarking methodology in conjunction with standardised visual survey methodology to give guidance on individual layer strengths and pinpoint rehabilitation needs. This benchmark methodology enables the determination of the relative structural condition of the pavement over length and in depth without the requirement for detailed as-built data. A further correlation study with calculated surface moduli and deflection bowl parameters is presented here for granular base pavements, which can enhance benchmarking methodology.
TL;DR: In this article, a literature review was done which yielded 72 typical causes of delay, and a questionnaire was sent to client, contractor, and consultant representatives in Malawi, which indicated that the top ten causes of delays in road construction projects are: shortage of fuel, insufficient contractor cash-flow, shortage of foreign currency for importation of materials and equipment, slow payment procedures adopted by the client in making progress payments, insufficient equipment, delay in relocating utilities, and shortage of construction materials.
Abstract: A study was conducted to identify the causes of delay in completing road construction projects in Malawi. A literature review was done which yielded 72 typical causes of delay, and a questionnaire was sent to client, contractor and consultant representatives in Malawi. The results were analysed using the Relative Importance Index (RII) and Spearman's Rank Correlation Coefficients, which indicated that the top ten causes of delay in Malawi are: shortage of fuel, insufficient contractor cash-flow, shortage of foreign currency for importation of materials and equipment, slow payment procedures adopted by the client in making progress payments, insufficient equipment, delay in relocating utilities, shortage of construction materials, delay in paying compensation to land owners, shortage of technical personnel, and delay in site mobilisation. The causes of delay are significant and should be given attention by client organisations, consultants and contractors to enable the timely completion of projects in future. It should also be noted that most of the causes of delay are not unique to Malawi, and have been observed in other southern African countries such as South Africa, Botswana and Swaziland. Recommendations are made to prevent similar causes of delay in future.
TL;DR: In this paper, the authors present a proposed method for assessing the potential stability of dolomite land based on the Method of Scenario Supposition proposed by Buttrick and Van Schalkwyk (1995).
Abstract: This paper presents a Proposed Method for Dolomite Land Hazard and Risk Assessment for characterising the potential stability of dolomite land, which is based on the Method of Scenario Supposition proposed by Buttrick and Van Schalkwyk (1995). The Proposed Method considers risk as well as hazard and reviews the classification of sites in terms of Dolomitic Area Designations as defined in the National Home Builders Registration Council's Home Building Manual (NHBRC 1999). The Proposed Method requires the evaluation of site geological conditions, provides a deductive framework within which professional judgement must be exercised, and offers a tool for the quantification and management of development risk. The provisions of the Housing Consumer Protection Measures Act (Act 95 of 1998) for the management of risk relating to housing development on dolomitic land are also presented.
TL;DR: Measurements show that an egg housed in a test structure and dropped from only 3 m can produce accelerations greater than 70 g, which closely matches the measured accelerations.
Abstract: An egg drop contest recently held at the University of Witwatersrand served to test engineering students' ability to solve non-standard problems. In this contest, students designed and built structures to protect their cargo - a raw egg. The structures were dropped 15 m onto a hard surface. The goal was to prevent damage to the egg upon impact. This paper explores some of the experimental and theoretical techniques that could be used to analyse and design a suitable impact resistant structure. The accelerations of the egg during free-fall and impact were measured by a miniature custom built accelerometer sensor and recorded by a data acquisition system. Measurements show that an egg housed in a test structure and dropped from only 3 m can produce accelerations greater than 70 g. The results from a theoretical model of impact presented in this paper closely matches the measured accelerations. The model predicts that if the test structure investigated would be dropped from 15 m, the egg would be subject to accelerations of approximately 100 g.
TL;DR: In this article, the authors present a review of previous techniques used to accelerate steel corrosion in reinforced concrete (RC) structures and propose a standard procedure to accelerate the process of steel corrosion by contaminating selected faces of reinforced concrete specimens with chlorides.
Abstract: Natural steel corrosion of reinforced concrete (RC) structures is a slow process which researchers find necessary to accelerate in laboratory tests to obtain needed damage in a short time. Regrettably, there is no standard procedure for accelerating steel corrosion in RC specimens. Researchers therefore continue to use various techniques to accelerate it. Unfortunately, structural damage and rate of steel corrosion are dependent on the accelerated corrosion technique used. Despite that, results obtained by researchers are applied by structural engineers and asset managers to in-service structures. This paper reviews previous techniques used to accelerate steel corrosion. Where possible it proposes standard procedures to accelerate steel corrosion. In other instances it points out needed further research. One of the procedures recommended in the paper is to contaminate selected faces of RC specimens with chlorides, as opposed to immersing samples in NaCl solution or adding chlorides to concrete mixes. It is also recommended to allow specimens to sufficiently dry during steel corrosion so as to promote steel corrosion.