Martin Mgangira - Academia.edu (original) (raw)
Papers by Martin Mgangira
Joernaal van die Suid-Afrikaanse Instituut van Siviele Ingenieurswese, 2001
This paper reports on a study of civil engineering students' perception of selected aspects o... more This paper reports on a study of civil engineering students' perception of selected aspects of the experiential learning programme, which is a required component of the National Diploma programme. The findings indicate that the students usually found the work assignments given to them manageable and usually to be relevant to their professional growth. While they usually found there was a link between the courses covered at the technikon and the tasks performed, the former only moderately prepared them for the experiential learning. They rated the overall experiential learning programme as good.
of the Built Environment at the CSIR. The paper is based on a study that was done while he was le... more of the Built Environment at the CSIR. The paper is based on a study that was done while he was lecturing at Nelson Mandela Metropolitan University. Contact details:
Joernaal van die Suid-Afrikaanse Instituut van Siviele Ingenieurswese, 2001
This paper reports on a study of civil engineering students' perception of selected aspects o... more This paper reports on a study of civil engineering students' perception of selected aspects of the experiential learning programme, which is a required component of the National Diploma programme. The findings indicate that the students usually found the work assignments given to them manageable and usually to be relevant to their professional growth. While they usually found there was a link between the courses covered at the technikon and the tasks performed, the former only moderately prepared them for the experiential learning. They rated the overall experiential learning programme as good.
International Journal of Engineering Education, 2003
Southern African Transport Conference (SATC 2018), CSIR ICC Pretoria, South Africa, 9-12 July 2018, Jul 1, 2018
The potential use of alternative materials is sometimes limited by the lack of performance data. ... more The potential use of alternative materials is sometimes limited by the lack of performance data. Appropriate laboratory studies can provide information on their performance. Two grades of fine grained fly ash samples without course fractions are being investigated for potential and appropriate application as road construction material. In the current phase of the study, the samples are treated with the minimum required amounts of lime and cement as well as an enzyme-based liquid stabilizer. The bulk mechanical properties are quantified using the unconfined compressive strength and static triaxial tests. The results show that moderate to high compressive and shear strength values are achievable with the minimum required amounts of cement and lime to stabilise the unclassified fine grained fly ash. The stabilisation with the enzyme-based liquid stabiliser has potential for application.
This paper presents experimental results of the flexural response of cement stabilised beams subj... more This paper presents experimental results of the flexural response of cement stabilised beams subjected to static pure bending using a simple four-point bending device. The device has been developed and manufactured for the purpose of field laboratory application. The main focus of the work is to demonstrate how the simple device can be used to qualitatively quantify the flexural response of a cement treated material and as a tool for quality control. Weathered granite was used as the host material. The material was treated by the addition of 2%, 3% and 5% cement by weight and four methods were used to cure the specimens. The effects of method of curing and cement content are illustrated. The deflection coefficient, the resistance to flexural deformation and the resilience are used to quantify the effect of method of curing and cement content. The test results indicate that the effect of the method of curing on the flexural characteristics of the cement-stabilised soil is dominated b...
The utilisation of advanced measurement techniques should assist in the characterization of pavem... more The utilisation of advanced measurement techniques should assist in the characterization of pavement materials at a micro-scale. The motivating factor for such an approach is that material properties at the micro-level have a critical role in the way materials respond to loading at the macro-level. The objective of the paper is to demonstrate how Scanning Electron Microscopy (SEM) as an example of advanced measurement techniques was used for material characterization. A range of samples of pavement engineering materials were examined at a micro-scale using the technique. Selected examples of material characterization are presented. The potential application of microstructural material characterization for the identification of key elements which provide the opportunity to understand fundamental behaviour of pavement engineering materials is demonstrated.
Joernaal van die Suid-Afrikaanse Instituut van Siviele Ingenieurswese, 2006
Soil improvement can be achieved through mechanical stabilisation using industrial byproducts. Cl... more Soil improvement can be achieved through mechanical stabilisation using industrial byproducts. Clayey soils were blended with waste foundry sand to examine its influence on the geotechnical engineering properties of the soils. The waste foundry sand was first subjected to standard geotechnical engineering testing. The effect of the foundry waste sand on the modification of the plasticity, swell potential, compaction characteristics and CBR values of the soils is demonstrated in this paper. The results show that the addition of waste foundry sand improves the performance potential of otherwise marginal materials for use in geotechnical engineering applications.
The delivery of the road infrastructure service to the communities is one of the core objectives ... more The delivery of the road infrastructure service to the communities is one of the core objectives of local municipalities and provincial transport, roads and infrastructure departments. These departments are expected to work within a similar framework of decision making for the delivery of road infrastructure. However, local decision making is key to how this is achieved and capacity constraints impact on the process. This paper is a reflection on observations made on two separate road projects, one at the municipal and the other at provincial sphere following investigations on the probable causes of premature failure the roads experienced. The investigation revealed inability to assess design and material usage during implementation of the projects to ensure that they were suitable for the intended purpose. Upon reflection, this could be attributed to capacity constraint.
The increased use of alternative materials, particularly streams of industrial byproducts in tran... more The increased use of alternative materials, particularly streams of industrial byproducts in transportation construction is motivated by the need to optimize construction of sustainable pavements. Fly ash has mostly been used as an additive in various applications in transportation construction. This paper presents a study on the use of a fly ash product as the primary constituent, rather than an additive. A fly ash product was lightly treated with cement in one test series, with lime and an enzyme based liquid stabilizer in the second and third test series respectively producing lightly stabilised fly ash (LSFA) material. Testing was aimed at fit-forpurpose assessment of the LSFA material in terms of mechanical properties. This is work in progress. The results have shown that the LSFA can achieve shear strength and modulus values highly appropriate and fit for design application in low volume roads.
Paper delivered at SATC 2017 - Southern African Transport Conference, CSIR ICC, Pretoria, 10-13 J... more Paper delivered at SATC 2017 - Southern African Transport Conference, CSIR ICC, Pretoria, 10-13 July 2017
Road Pavement Material Characterization and Rehabilitation, 2009
The characteristics of the roadbed material are critical to the overall performance of the paveme... more The characteristics of the roadbed material are critical to the overall performance of the pavement. The paper presents examples with discussion of the form of distress experienced within the pavement layers, based on observations made during the profiling exercise of an investigation into the causes of the premature failure of a pavement. The field investigation entailed a detailed inspection and recording of the profile exposed in test pits, with particular attention being paid to areas with cracks, noting their positions and extent within the pavement layers. The focus of the paper is on the observed orientation of crack propagation within the pavement layers. It is shown that the crack propagation is not always in the vertical plane. This has implications in dealing with crack sealing procedures. The causes of the observed distress were attributed to the behavior of the roadbed as it experienced fluctuating moisture conditions.
Recent Developments in Evaluation of Pavements and Paving Materials, 2014
The quantification of discrete aggregate particle characteristics should allow for an increased u... more The quantification of discrete aggregate particle characteristics should allow for an increased understanding of how these influence the performance of pavement materials in general. Two advanced techniques, the three dimensional (3-D) laser scanning and scanning electron microscopy (SEM), are considered for the characterization of discrete particles of aggregates and sands, respectively. This paper highlights examples of the use of both 3-D laser scanning and SEM techniques with the main objective of illustrating the application in the characterization of unbound materials. The results of image analysis from SEM and 3-D laser scanning device provided information in quantifying and identifying the differences between aggregate particles which may influence the overall performance of unbound pavement materials.
The paper discusses a road rehabilitation project and a sports complex, where the underlying in s... more The paper discusses a road rehabilitation project and a sports complex, where the underlying in situ materials were typical African black cotton soils known for their expansive characteristics. Field investigations were undertaken to discern the main causes of the ...
... Thus assessment of the effectiveness of the method of treatment or used product in the soilst... more ... Thus assessment of the effectiveness of the method of treatment or used product in the soilstabilization can be achieved by determining change in the properties of the treated ... Investigation of the effectiveness and mechanisms of enzyme products for subgrade stabilization. ...
Forum, Dec 1, 2014
Three dimensional (3-D) laser scanning has recently proved to be an ideal technique for quantifyi... more Three dimensional (3-D) laser scanning has recently proved to be an ideal technique for quantifying aggregate particle shape parameters. This is because 3-D laser scanners measure fine details and capture free-form shapes. This paper presents some results of an ongoing study, which utilises 3-D laser scanning technology to quantify aggregate shape parameters. Specific correlations and shape parameters have been considered. The results have shown that meaningful correlations exist between 3-D sphericity and aspect ratio as well as between specific surface area and the particle diameter as defined in this paper. The results of the current study are consistent with generally accepted relationships between shape parameters and particle size, further validating the application of the 3-D laser scanning technology.
The fundamental shape/morphological properties of coarse aggregates including form, angularity, a... more The fundamental shape/morphological properties of coarse aggregates including form, angularity, and surface texture are known to influence the performance of pavements. The coarse aggregate shape properties are affected by many factors, amongst others, the properties of the parent rock and the type of crusher or crushing operations. Therefore, quantification of the effects of the crusher type on the aggregate shape properties is important as it influences the bulk properties of pavement materials and therefore performance. Recent studies have demonstrated that laser scanning technique can be employed to better quantify the three-dimensional (3-D) shape properties of aggregate materials used in pavements. In this paper, the shape properties of quartzite aggregates crushed by using four different types of crushers were investigated. The results have demonstrated the extent to which the aggregate shape indices computed using laser scan results can be used to distinguish aggregate by-product from different crushers.
Africa Community Access Partnership (AfCAP) is supporting research activities in Africa region. O... more Africa Community Access Partnership (AfCAP) is supporting research activities in Africa region. One of the projects supported by AfCAP in research activities was to build capacity and implement a laboratory skills development programme for laboratories of the Local Government Infrastructure and Transportation Research Centre (LoGITReC) in Tanzania. Laboratory capacity building efforts included human resources development, establishment of laboratory quality assurance procedures, basic laboratory work inventory system and equipment procurement. Development of general operational protocols which would provide guidance for the everyday general technical administration of the laboratory. The capacitation of the laboratory was aimed at providing capability to support the execution of the research programme. Staff at the LoGITReC laboratory and three other regional laboratories were the beneficiaries of the capacity building project. The paper highlights experiences as expressed by LoGITReC (the beneficiaries) on the capacity building programme. A positive contribution to skills development is evident and as a result of the establishment of the laboratories, increased access to testing facilities for materials used in rural road works in Tanzania has been realised.
Joernaal van die Suid-Afrikaanse Instituut van Siviele Ingenieurswese, 2001
This paper reports on a study of civil engineering students' perception of selected aspects o... more This paper reports on a study of civil engineering students' perception of selected aspects of the experiential learning programme, which is a required component of the National Diploma programme. The findings indicate that the students usually found the work assignments given to them manageable and usually to be relevant to their professional growth. While they usually found there was a link between the courses covered at the technikon and the tasks performed, the former only moderately prepared them for the experiential learning. They rated the overall experiential learning programme as good.
of the Built Environment at the CSIR. The paper is based on a study that was done while he was le... more of the Built Environment at the CSIR. The paper is based on a study that was done while he was lecturing at Nelson Mandela Metropolitan University. Contact details:
Joernaal van die Suid-Afrikaanse Instituut van Siviele Ingenieurswese, 2001
This paper reports on a study of civil engineering students' perception of selected aspects o... more This paper reports on a study of civil engineering students' perception of selected aspects of the experiential learning programme, which is a required component of the National Diploma programme. The findings indicate that the students usually found the work assignments given to them manageable and usually to be relevant to their professional growth. While they usually found there was a link between the courses covered at the technikon and the tasks performed, the former only moderately prepared them for the experiential learning. They rated the overall experiential learning programme as good.
International Journal of Engineering Education, 2003
Southern African Transport Conference (SATC 2018), CSIR ICC Pretoria, South Africa, 9-12 July 2018, Jul 1, 2018
The potential use of alternative materials is sometimes limited by the lack of performance data. ... more The potential use of alternative materials is sometimes limited by the lack of performance data. Appropriate laboratory studies can provide information on their performance. Two grades of fine grained fly ash samples without course fractions are being investigated for potential and appropriate application as road construction material. In the current phase of the study, the samples are treated with the minimum required amounts of lime and cement as well as an enzyme-based liquid stabilizer. The bulk mechanical properties are quantified using the unconfined compressive strength and static triaxial tests. The results show that moderate to high compressive and shear strength values are achievable with the minimum required amounts of cement and lime to stabilise the unclassified fine grained fly ash. The stabilisation with the enzyme-based liquid stabiliser has potential for application.
This paper presents experimental results of the flexural response of cement stabilised beams subj... more This paper presents experimental results of the flexural response of cement stabilised beams subjected to static pure bending using a simple four-point bending device. The device has been developed and manufactured for the purpose of field laboratory application. The main focus of the work is to demonstrate how the simple device can be used to qualitatively quantify the flexural response of a cement treated material and as a tool for quality control. Weathered granite was used as the host material. The material was treated by the addition of 2%, 3% and 5% cement by weight and four methods were used to cure the specimens. The effects of method of curing and cement content are illustrated. The deflection coefficient, the resistance to flexural deformation and the resilience are used to quantify the effect of method of curing and cement content. The test results indicate that the effect of the method of curing on the flexural characteristics of the cement-stabilised soil is dominated b...
The utilisation of advanced measurement techniques should assist in the characterization of pavem... more The utilisation of advanced measurement techniques should assist in the characterization of pavement materials at a micro-scale. The motivating factor for such an approach is that material properties at the micro-level have a critical role in the way materials respond to loading at the macro-level. The objective of the paper is to demonstrate how Scanning Electron Microscopy (SEM) as an example of advanced measurement techniques was used for material characterization. A range of samples of pavement engineering materials were examined at a micro-scale using the technique. Selected examples of material characterization are presented. The potential application of microstructural material characterization for the identification of key elements which provide the opportunity to understand fundamental behaviour of pavement engineering materials is demonstrated.
Joernaal van die Suid-Afrikaanse Instituut van Siviele Ingenieurswese, 2006
Soil improvement can be achieved through mechanical stabilisation using industrial byproducts. Cl... more Soil improvement can be achieved through mechanical stabilisation using industrial byproducts. Clayey soils were blended with waste foundry sand to examine its influence on the geotechnical engineering properties of the soils. The waste foundry sand was first subjected to standard geotechnical engineering testing. The effect of the foundry waste sand on the modification of the plasticity, swell potential, compaction characteristics and CBR values of the soils is demonstrated in this paper. The results show that the addition of waste foundry sand improves the performance potential of otherwise marginal materials for use in geotechnical engineering applications.
The delivery of the road infrastructure service to the communities is one of the core objectives ... more The delivery of the road infrastructure service to the communities is one of the core objectives of local municipalities and provincial transport, roads and infrastructure departments. These departments are expected to work within a similar framework of decision making for the delivery of road infrastructure. However, local decision making is key to how this is achieved and capacity constraints impact on the process. This paper is a reflection on observations made on two separate road projects, one at the municipal and the other at provincial sphere following investigations on the probable causes of premature failure the roads experienced. The investigation revealed inability to assess design and material usage during implementation of the projects to ensure that they were suitable for the intended purpose. Upon reflection, this could be attributed to capacity constraint.
The increased use of alternative materials, particularly streams of industrial byproducts in tran... more The increased use of alternative materials, particularly streams of industrial byproducts in transportation construction is motivated by the need to optimize construction of sustainable pavements. Fly ash has mostly been used as an additive in various applications in transportation construction. This paper presents a study on the use of a fly ash product as the primary constituent, rather than an additive. A fly ash product was lightly treated with cement in one test series, with lime and an enzyme based liquid stabilizer in the second and third test series respectively producing lightly stabilised fly ash (LSFA) material. Testing was aimed at fit-forpurpose assessment of the LSFA material in terms of mechanical properties. This is work in progress. The results have shown that the LSFA can achieve shear strength and modulus values highly appropriate and fit for design application in low volume roads.
Paper delivered at SATC 2017 - Southern African Transport Conference, CSIR ICC, Pretoria, 10-13 J... more Paper delivered at SATC 2017 - Southern African Transport Conference, CSIR ICC, Pretoria, 10-13 July 2017
Road Pavement Material Characterization and Rehabilitation, 2009
The characteristics of the roadbed material are critical to the overall performance of the paveme... more The characteristics of the roadbed material are critical to the overall performance of the pavement. The paper presents examples with discussion of the form of distress experienced within the pavement layers, based on observations made during the profiling exercise of an investigation into the causes of the premature failure of a pavement. The field investigation entailed a detailed inspection and recording of the profile exposed in test pits, with particular attention being paid to areas with cracks, noting their positions and extent within the pavement layers. The focus of the paper is on the observed orientation of crack propagation within the pavement layers. It is shown that the crack propagation is not always in the vertical plane. This has implications in dealing with crack sealing procedures. The causes of the observed distress were attributed to the behavior of the roadbed as it experienced fluctuating moisture conditions.
Recent Developments in Evaluation of Pavements and Paving Materials, 2014
The quantification of discrete aggregate particle characteristics should allow for an increased u... more The quantification of discrete aggregate particle characteristics should allow for an increased understanding of how these influence the performance of pavement materials in general. Two advanced techniques, the three dimensional (3-D) laser scanning and scanning electron microscopy (SEM), are considered for the characterization of discrete particles of aggregates and sands, respectively. This paper highlights examples of the use of both 3-D laser scanning and SEM techniques with the main objective of illustrating the application in the characterization of unbound materials. The results of image analysis from SEM and 3-D laser scanning device provided information in quantifying and identifying the differences between aggregate particles which may influence the overall performance of unbound pavement materials.
The paper discusses a road rehabilitation project and a sports complex, where the underlying in s... more The paper discusses a road rehabilitation project and a sports complex, where the underlying in situ materials were typical African black cotton soils known for their expansive characteristics. Field investigations were undertaken to discern the main causes of the ...
... Thus assessment of the effectiveness of the method of treatment or used product in the soilst... more ... Thus assessment of the effectiveness of the method of treatment or used product in the soilstabilization can be achieved by determining change in the properties of the treated ... Investigation of the effectiveness and mechanisms of enzyme products for subgrade stabilization. ...
Forum, Dec 1, 2014
Three dimensional (3-D) laser scanning has recently proved to be an ideal technique for quantifyi... more Three dimensional (3-D) laser scanning has recently proved to be an ideal technique for quantifying aggregate particle shape parameters. This is because 3-D laser scanners measure fine details and capture free-form shapes. This paper presents some results of an ongoing study, which utilises 3-D laser scanning technology to quantify aggregate shape parameters. Specific correlations and shape parameters have been considered. The results have shown that meaningful correlations exist between 3-D sphericity and aspect ratio as well as between specific surface area and the particle diameter as defined in this paper. The results of the current study are consistent with generally accepted relationships between shape parameters and particle size, further validating the application of the 3-D laser scanning technology.
The fundamental shape/morphological properties of coarse aggregates including form, angularity, a... more The fundamental shape/morphological properties of coarse aggregates including form, angularity, and surface texture are known to influence the performance of pavements. The coarse aggregate shape properties are affected by many factors, amongst others, the properties of the parent rock and the type of crusher or crushing operations. Therefore, quantification of the effects of the crusher type on the aggregate shape properties is important as it influences the bulk properties of pavement materials and therefore performance. Recent studies have demonstrated that laser scanning technique can be employed to better quantify the three-dimensional (3-D) shape properties of aggregate materials used in pavements. In this paper, the shape properties of quartzite aggregates crushed by using four different types of crushers were investigated. The results have demonstrated the extent to which the aggregate shape indices computed using laser scan results can be used to distinguish aggregate by-product from different crushers.
Africa Community Access Partnership (AfCAP) is supporting research activities in Africa region. O... more Africa Community Access Partnership (AfCAP) is supporting research activities in Africa region. One of the projects supported by AfCAP in research activities was to build capacity and implement a laboratory skills development programme for laboratories of the Local Government Infrastructure and Transportation Research Centre (LoGITReC) in Tanzania. Laboratory capacity building efforts included human resources development, establishment of laboratory quality assurance procedures, basic laboratory work inventory system and equipment procurement. Development of general operational protocols which would provide guidance for the everyday general technical administration of the laboratory. The capacitation of the laboratory was aimed at providing capability to support the execution of the research programme. Staff at the LoGITReC laboratory and three other regional laboratories were the beneficiaries of the capacity building project. The paper highlights experiences as expressed by LoGITReC (the beneficiaries) on the capacity building programme. A positive contribution to skills development is evident and as a result of the establishment of the laboratories, increased access to testing facilities for materials used in rural road works in Tanzania has been realised.