Browsing Civil Engineering by Title
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Rekha, A.; Raju, V.C.C. (University of Botswana, NaN, 1999)[more][less]
Abstract: The stress-attention in cascade reliability has been studied when both stess and strength follow Rayleigh distribution. The expression for the relaibility R(n), for a system survive with the first (n-1) components failed and the n component active, is obtained R(n) is calculated numerically, for n=1,2,3 and 4, for different values of the parameter p and the attention factor k. It has been found that with lower attention factors in high degree of reliability can be attained. URI: http://hdl.handle.net/10311/677 Files in this item: 1
Rekha_BJT_1999.pdf (887.1Kb) -
Kalabamu, F. (Elsevier http://www. doi:10.1016/j.habitatint.2003.09.005, NaN, 2005)[more][less]
Abstract: The purpose of this essay is to identify gender contracts in self-help housing construction. Gender contracts have been defined as invisible power relationships that determine roles, responsibilities, privileges, status, sexuality and behaviour of men and women within households, communities, the market and the state. Gender contracts shape social, economic, political and sexual relationships in what people often refer to as ‘our culture’. Various gender contracts constitute a gender system (e.g. patriarchy or matriarchy) under which general rules, perceptions, hierarchies and privileges are formulated, refined and preserved. The paper notes that although the advent of colonialism and capitalism did not replace patriarchal structures in Botswana, they set in new political and production systems that upset the traditional power base and provided opportunities for women to challenge traditional gender contracts—notably the marriage contract that had hitherto been used to oppress women. The paper further notes that despite women having made inroads into male domains, there has surfaced new sites and forms of female subordination largely due to gendered inequalities in accessing and controlling contemporary critical resources (land, money, modern technical skills and formal employment) as well as continued male dominance of community and state structures. Taking Lobatse as a case study, the paper tries to identify gender contracts formed as a result of men’s takeover of construction activities which were traditionally undertaken by women in Botswana. It notes that besides dominating construction work, men control access to land, building skills, housing finance, and the entire self-help housing process in Lobatse, thereby forcing women into subordinate positions from which they have to bargain or negotiate new gender contracts. URI: http://hdl.handle.net/10311/430 Files in this item: 1
Kalabamu_HI_2005.pdf (2.325Mb) -
Malumbela, G.; Alexander, M.; Moyo, P. (Elsevier http://www.linkinghub.elsevier.com/retrieve/pii/S0958946508000784, NaN, 2008)[more][less]
Abstract: This paper presents a discussion on a paper authored by Chung et al. [Chung L, Najm H, Balaguru P. Flexural behaviour of concrete slabs with corroded bars. Cement Concr Compos 2008;30:184-93]. URI: http://hdl.handle.net/10311/426 Files in this item: 1
Malumbela_CCC_2008.pdf (146.7Kb) -
Ngowi, A.B.; Mselle, P.C. (MCB University Press http://www.emeraldinsight.com/10.1108/02632779810233511, November NaN, 1998)[more][less]
Abstract: By involving the beneficiaries of a facility such as housing or an irrigation scheme, at the various stages of the project, it is possible to build their capacity in relation to the facility, which may contribute to the sustainability of the project beyond the disbursement period. A study carried out in Botswana found that the intensity of community participation at the various stages of facility development is influenced by the complexity of the technology adopted and the willingness of the facility managers to involve the community from the early stages of the project. Based on these findings, this paper proposes a framework which may be followed to achieve this end. URI: http://hdl.handle.net/10311/407 Files in this item: 1
Ngowi_Fac_1998.pdf (382.5Kb) -
Ngowi, A.B. (MCB University Press; Emerald Group Publishing Ltd; http://www.emeraldinsight.com/, NaN, 1997)[more][less]
Abstract: The design and construction of infrastructure facilities such as road network, water supply and sewage disposal in Botswana, have often been done in a top-bottom fashion where the government or local authority decides what is good for the community. While the design and construction of infrastructure facilities require technical knowledge, heavy equipment and proper supervision, their management hardly requires these resources to the same extent. This offers the beneficiaries of the facilities an opportunity to manage their day-to-day operations and maintenance. Reports on an approach adopted to engage the community in the management of local road network, water supply and sanitation in three major villages in Botswana. It analyses the method previously employed in managing these facilities and outlines the benefits which will accrue when this approach is fully operational. Concludes by underlining the fact that, for community-managed facilities to work, the people in the community need to participate in all the stages of the project (i.e. planning, design, construction and eventually maintenance). URI: http://hdl.handle.net/10311/257 Files in this item: 2
license.txt (1.998Kb) -
Ngowi, A.B. (MCB University Press. http//:www.emerald.library.com/ft, NaN, 2001)[more][less]
Abstract: The primary purpose of forming alliance in the construction industry is to pool together the resources of the participating partners in order to form a team that has a competitive advantage. Each partner in an alliance has its own competence and market share that do not necessarily fall under the alliance as common resources. Therefore, although the competitive advantage aimed at when forming an alliance is for common profits, each partner has a possibility of using it (the competitive advantage) for private profits (i.e. activities that do not fall under the alliance). Using a case study from Botswana, this paper argues that a construction alliances strives as long as the profits created by common activities are substantially higher that the ones that can be created by private activities. Once one of the partners in the alliance can create the competitive advantage in question on its own, it will opt out of the alliance through such mechanisms as withdrawing some of its key contributions to the alliance. URI: http://hdl.handle.net/10311/344 Files in this item: 1
Ngowi_2001_JEIMngt.pdf (1.186Mb) -
Ngowi, A.B.; Iwisi, D.; Mushi, R. (Taylor and Francis Ltd. http://www.tandf.co.uk/journals/titles/09613218.asp, NaN, 2002)[more][less]
Abstract: Traditionally, competitive advantage has been based upon large-scale production and accumulation of large quantities of physical and financial assets. Large financially capable firms, particularly Multi-national Corporations (MNCs) and large construction firms create competitive advantages and sustain them through the use of such defence mechanisms as entry barriers and other competition-impeding features of industry structure. Small firms in developing countries, especially in Africa can hardly mobilize financial resources to match the MNCs and the large construction firms, nor can they employ similar defence mechanisms due to their lack of global reach.Using the construction industry in Botswana, the paper reports on a pilot study that investigated the factors that are crucial to creating constantly changing competitive advantage in the context of low financial resources. It concludes by emphasizing that firms operating in low financial contexts should create dynamic competitive advantages instead of imitating the strategies used by large financially capable firms. URI: http://hdl.handle.net/10311/264 Files in this item: 1
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Ssegawa, J.K. (University of Botswana, http://www.ub.bw, NaN, 1999)[more][less]
Abstract: By the turn of the century, Botswana will be 34 years old as an independent nation. Reflecting on the past, is a background of tremendous achievements from a socio-economic development perspective. The achievements could not have been possible if it was not for the contribution. The construction industry’s (CI) contribution to socio-economic development may be viewed from many areas, among them, creating employment, wealth and demand for manufactured goods, infrastructure and producing factors of production (e.g. office space, factory shells, roads, etc) for other sectors. However, the relationship between the general economy and the CI has not been established explicitly despite numerous studies. Using Botswana’s CI and the economy, some of the paradigms proposed in previous studies revisited. URI: http://hdl.handle.net/10311/843 Files in this item: 1
Ssegawa_BJT_1999.pdf (1.185Mb) -
Ssegawa, J.K. (University of Botswana http://www.ub.bw, NaN, 1999)[more][less]
Abstract: By the turn of the century,Botswana will be 34 years old as an independent nation. Reflecting on the past, is a background of tremedous achievements from a socio-economic development perspective.The achievement could not have been possible if it was not for the contribution from the various sectors of the economy, such as mining, agriculture, manufacturing and of course, construction. The construction industry's (CI) contribution to socio-economic development may be viewed from many areas, among them, creating employment, wealth and demand for manufactured goods, infrastructure and producing factors of production(e.g. office space, factory shells, roads, etc.) for other sectors. However, the relationship between the general economy and the CI has not been established explicitly despite the numerous studies. Using Botswana's CI and the economy, some of the paradigms proposed in previous studies revisited. URI: http://hdl.handle.net/10311/706 Files in this item: 1
Ssegawa_BJT_1999.pdf (1.950Mb) -
Mwewa, W.L. (University of Botswana, www.ub.bw, NaN, 1999)[more][less]
Abstract: The demand for adequate training of artisans and apprentices in the construction industry cannot be over emphasized in view of the rapid changes the industry is undergoing. Many of of these changes are continously taking place especially in the areas of utilization and maintainability of construction materials. The local vocational institutions should vigorously embark on reviewing the vocational education and training. This will result in the supply of cadres with acceptible quality of training in order to meet the challenges of the building industry. In spite of the ten years of involvement by the local vocational institutions in the training of artisans and apprentices there is still shortage of skilled manpower. The aim of the paper, therefore, is to assess the relevance of the vocational training programs and the trends of output of artisans and apprentices trained before and after the second construction boom from boom from 1986 to 1990 and 1992 to 1996. URI: http://hdl.handle.net/10311/882 Files in this item: 1
Mwewa_BJT_1999.pdf (1.091Mb) -
Abadjieva, T. (University of Botswana, NaN, 1998)[more][less]
Abstract: Investigations of the influence of various factors on the modulus of elasticity and deformability of different types of lightweight concrete are presented.The results show that the modulus are not constant and decrease with the increase of the level of applied stress. Aggregate proposity and volume fraction effects the modulus of elasticity and the modulus of deformability of concrete. Using different concrete mixes of varying strength, it was confirmed that the the modulus of elasticity and the comprehensive strength of concrete are directly proportioned. The modulus of elasticity per unit strength decreases with the age of concrete. As lightweight concrete is a heterogeneous, multiphase material, the volume fraction and modulus of elasticity of the principal constituents influence the modulus of elasticity of the composite material. URI: http://hdl.handle.net/10311/611 Files in this item: 1
Abajieva_BJT_1998.pdf (1.208Mb) -
Sahu, B.K.; Jayaram, S. (University of Botswana, NaN, 2000)[more][less]
Abstract: Alarmingly high accumulation of fly ash has led geochemical engineers into finding a solution for the use of flyash as a construction material in the recent past. As of now, although the material has been used in a limited way in the construction of roads, embarkments,dykes and by cement industries, most of it is still dumped as a waste material. There is a general opinion mongst teh Geochemical engineers that fly ash is a non-hazardous material. However, the authors felt that it may not be entirely true due to the fact that fly ash does contain quite a significant proportion of soluble salts. These salts would leak into water if fly ash comes into contact with water or if the ground water leaked through a bed of fly ash. The investigation revealed that Dissolved Oxygen of fly ash polluted tap and clean water is reduced to a level far below the permissible limit for aquatic life. The author would like to emphasise that the findings of the present investigation are being submitted to open an agenda on the issue of water pollution by the fly ash leachate, may it be ground water, water in the vicinity of the ash being used in the construction of dykes,dams, river training structures or for reclamation on sea shores. URI: http://hdl.handle.net/10311/601 Files in this item: 1
Sahu_BJT_2000.pdf (863.8Kb) -
Ssegawa, J.K.; Masambaji, C.N. (Faculty of Engineering and Technology, University of Botswana, www.ub.bw, April NaN, 2011)[more][less]
Abstract: To deliver project effectively is of paramount importance because most of the world population depend on services delivered by projects. Reports from various countries around the world, including Botswana, still indicate poor project delivery. Several causes may be advanced including ineffective project control. Devising means to alleviate the control problem is therefore, of great importance. Scholars and practitioners have suggested various techniques that monitor and keep track of projects. One of them is the earned value analysis(EVA) which touted by many as an efficient yet effective control system because of its ability to control scope, cost and time. Based on this premise, the study reported in this paper investigated possible use of EVA in building projects in Botswana. The investigation was two fold, firstly, through a questionnaire, quantity surveyors (QSs) were requested to indicate whether they have use the EVA on any building project in Botswana. Results from this survey indicated that EVA is not used at all in Botswana. In fact, majority (63%) of the QSs have not heard of the system before. The second phase of the study investigated its possible use, that is, if using EVA is more adventageous than the convectional control method (CCM). Results indicated that EVA system provide quality information that was well structured, more objective, and easily accessible to all key stakeholders in a timely and understandable manner. However, to use EVA system several challenges were also indentified which included firstly, the need to train the key players in the EVA technique.; the need to change the project regime from arms-length to a cooperative on to allow transfer and sharing of information in the design and construction phases of a project; increasing the use of IT; completing design before tendering even for other trades; and nominating sub-contractors as soon as the main contract is appointed. URI: http://hdl.handle.net/10311/875 Files in this item: 1
Ssegawa_BJT_2011.pdf (2.489Mb) -
Kanyeto, O.J. (University of Botswana, NaN, 1999)[more][less]
Abstract: Advantages of using Finite Element Method (FEM)in structural engineering practice are presented in this paper.A brief description of the method is given with the aim to illustrate the rich solid mathematical basis that makes its foundation.The paper then presents some guidelines on how to build a good model for Finite Element Analysis (FEA) purposes. The guideline emphasises the need for the analyst to have a clear understanding of the physical problem and of the behaviour of the elements he employs to carry out the analysis.A practical example presented in order to illustrate the type of analysis and results that can be obtained from a commercial FE software package. This example forms part of the research work that was carried out by the author.And finally, it is recommended that all practicing structural engineers must learn the basics of finite element method, and be equiped with some FE software packagess. Since it is the most commonly used and trusted method in the world of engineering today. In order to keep up with the rest of the world in engineering advancements, the author finds it vital to equip all engineers with the latest engineering software packages and to elevate continuing engineering education. URI: http://hdl.handle.net/10311/681 Files in this item: 1
kanyeto_BJT_1999.pdf (1.860Mb) -
Ngowi, A.B. (Taylor and Francis, http://www.pdfserve.informaworld.com/940578_73138570, NaN, 1997)[more][less]
Abstract: This paper examines the strategy of employing a hybrid combination of indigenous and modern housing construction technologies. Using a Botswana village as a case study, this paper examines four traditional house types in relation to the household income, skills, materials and aspects which could be improved by adapting industrialized methods. Using experimental houses, the case study provides the costs, benefits, potential problems and implementation considerations. The paper discusses the weaknesses and virtues of traditional construction technologies, how appropriate aspects from modern technologies can be incorporated or adapted into traditional methods and the implications for developing appropriate, affordable housing technologies URI: http://hdl.handle.net/10311/370 Files in this item: 1
Ngowi_1997_BRI.pdf (800.7Kb) -
Ngowi, A.B. (MCB University Press, http://www.emerald-library.com, NaN, 2000)[more][less]
Abstract: Total quality management (TQM) as an integrated approach to management that represents a holistic management philosophy, rather than a series of techniques, is embedded with cultural values and assumptions that are consistent with its culture of origin. This study aims to determine the outcome of implementing TQM in a place that does not share its cultural base. A survey of 100 construction firms in Botswana found that, although the values embedded in TQM could be adopted within the organisations into which it is implemented, the cultural context of the greater society resisted some of the values. It was concluded that, for TQM to be successful in a particular cultural setting, it has to take on some of the host cultural values URI: http://hdl.handle.net/10311/350 Files in this item: 1
Ngowi_2000_JEIM.pdf (915.4Kb) -
Ngowi, A.B. (MCB University Press; Emerald Publishing Group Ltd; http://www.mcbup.com/research_registers/quality.asp, NaN, 2000)[more][less]
Abstract: Total quality management (TQM) as an integrated approach to management that represents a holistic management philosophy, rather than a series of techniques, is embedded with cultural values and assumptions that are consistent with its culture of origin. This study aims to determine the outcome of implementing TQM in a place that does not share its cultural base. A survey of 100 construction firms in Botswana found that, although the values embedded in TQM could be adopted within the organisations into which it is implemented, the cultural context of the greater society resisted some of the values. It was concluded that, for TQM to be successful in a particular cultural setting, it has to take on some of the host cultural values. URI: http://hdl.handle.net/10311/170 Files in this item: 2
license.txt (1.998Kb)ngowi1.pdf (97.37Kb) -
Sahu, B.K.; Mathur, S.; Kemsley, B. (University of Botswana, NaN, 2004)[more][less]
Abstract: The national road network continues to play a fundamental and catalytic role in the promotion of social and economic development of Botswana. However, a combination of adverse climatic and geological factors, such as scarcity of conventional road building materials, near absence of a non saline surface water, and climatic extremes have dictated the need for innovative engineering approaches to highway design, construction and maintenance. In recent years application of fly ash has been considered in road construction with great interest. Fly ash is a pozzolanic material, which in the presence of water combines with lime to produce a cementetious material with excellent structural properties. Attempts have, therefore, been made at Botswana Roads Department in collaboration with University of Botswana to explore the feasibility of utilizing fly ash alone to improve the physical and strength characteristics of locally available non-standard marginal materials. The results indicate that with the addition of fly ash plasticity dereases while California Bearing Ration (CBR) increases for calcrete and other locally available marginal materials for road construction. With appropriate amount of fly ash and an adequate curing the material can be improved to meet the requirement of base and sub-base coarse. URI: http://hdl.handle.net/10311/644 Files in this item: 1
Sahu_BJT_2004.pdf (606.5Kb) -
Ngowi, A.B. (Elsevier, NaN, 1997)[more][less]
Abstract: The traditional developed earth as one of the most important construction materials by taking cognizance of the strength requirements, durability of resulting structures and the environmental concern in processing and using the material. Overthe years, however, modern earth construction has replaced the traditional methods. Unfortunately,these methods are also accompanied by high energy consumption and environmental degradation.This paper examines the methods of improving earth construction in two major villages in Botswana.Tests with different stabilizers showed that only certain proportions were effective and it was concluded that the traditional earth construction may be improved by using certain ratios of cement and lime as stabilizers. URI: http://hdl.handle.net/10311/606 Files in this item: 1
Ngowi_CBM_1997.pdf (968.2Kb) -
Malumbela, G.; Moyo, P.; Alexander, M. (Elsevier http://www.elsevier.com/locate/conbuiltmat, NaN, 2011)[more][less]
Abstract: Corrosion crack widths are often used by structural engineers in the field to predict level of steel corrosion as well as residual load-bearing capacities of corroding RC structures. This paper presents further work on this matter but with focus on corrosion crack patterns and how they affect rate of crack widening. It is based on results from a research where 17 quasi-full-scale (153 254 3000 mm) RC beams were corroded under various levels of sustained loads. The rate of widening of corrosion crack widths was found to be very much dependent on crack patterns. Deformation of cover concrete under each crack pattern was discussed. It was found that at maximum crack widths below 0.6 mm, the majority of beams exhibited nearly similar crack patterns as well as rate of widening of corrosion cracks. A mass loss of steel of 1% corresponded to a maximum crack width between 0.14 and 0.22 mm. At large crack widths (>0.6 mm), various beams exhibited very different rates of crack widening. It was shown that at crack widths above 0.6 mm, to be conservative an increase in mass loss of steel of 1% corresponded to corrosion crack widening of 0.02 mm. URI: http://hdl.handle.net/10311/676 Files in this item: 1
Malumbela1_CBM_2010.pdf (1.399Mb)