The Influence of Quality Control Mechanism Implemented by Consultants on Quality Assurance of Road Projects: A Case of Dar es Salaam Metropolitan Development Projects, Tanzania

https://doi.org/10.51867/ajernet.6.2.22

Authors

Keywords:

Quality, Quality Control, Quality Control Mechanism, Quality Assurance

Abstract

This paper aimed to examine the influence of quality control mechanisms (evaluation of work executed, supervision of work, advising on proper execution of work and inspection of work executed) implemented by consultants on quality assurance of road projects in Tanzania so as to provide a comprehensive understanding of the relationship between quality control mechanisms and quality assurance, which stakeholders can make informed decisions to improve project outcomes and enhance overall infrastructure quality. This study was guided by agency theory. The study employed a case study research design that utilized a quantitative research approach, involving 122 respondents from the population of 175 randomly selected in the 50 road projects under Dar es Salaam Metropolitan Development Project (DMDP), but valid responses were 110. The data was collected using self-administered questionnaire, and the collected data were analyzed by factor analysis and multiple regression analysis. From the analysis, the findings demonstrated that the evaluation has a negative relationship (-1.680, p < .022), implying that lower evaluation of work executed scores correspond to lower project quality. Conversely, both supervision of work (1.375, p < .001) and advising on proper execution of work (1.151, p < .026) show positive relationships with project quality, implying that higher levels of supervision and effective advising contribute to enhanced outcomes of the projects. Inspection of work executed failed to serve as a significant predictor (0.011, p >.949) which shows that its effectiveness on quality assurance did not show up as expectations compared to other mechanisms. The research reveals consultants' application of evaluation procedures and supervisory techniques together with advising practices to uphold road construction quality standards. The research finds that evaluation, supervision, and advising serve as essential quality control tools used by consultants but recognizes the need to enhance inspection practices for better process effectiveness. Consultants should prioritize rigorous supervision practices to make sure construction activities comply with specifications while adhering to safety regulations and quality standards. Adequate quality assurance requires full-time supervision through regular site visits and progress reviews combined with stakeholder coordination.

Dimensions

African Development Bank Group. (2021). Tanzania: Dar es Salaam Metropolitan Development Project (DMDP). https:// www. afdb. org/ en/ documents/document/tanzania-dar-es-salaam-metropolitan-development-project-dmdp-34441

Aithal, A., & Aithal, P. S. (2020). Development and Validation of Survey Questionnaire & Experimental Data - A Systematical Review-based Statistical Approach. SSRN Electronic Journal. https://doi.org/10.2139/ssrn.3724105 DOI: https://doi.org/10.2139/ssrn.3724105

Asiedu, R. O., Owusu-Manu, D.-G., Gyimah, S., Edwards, D. J., & Amoakwa, A. B. (2024). Evaluating the adoption barriers of circular business models in the Ghanaian construction industry. Benchmarking: An International Journal. https://doi.org/10.1108/BIJ-03-2024-0202 DOI: https://doi.org/10.1108/BIJ-03-2024-0202

Brooks, T., Gunning, J. G., Spillane, J. P., & Cole, J. (2021). Regulatory decoupling and the effectiveness of the ISO 9001 quality management system in the construction sector in the UK - a case study analysis. Construction Management and Economics, 39(12), 988-1005. https://doi.org/10.1080/01446193.2021.1983186 DOI: https://doi.org/10.1080/01446193.2021.1983186

Dwiaryanti, R. M., Dinariana, D., & Suryani, F. (2021). The Role of Construction Management Consultants in Building Construction Procurement with Integrated Construction Method. International Journal of Scientific and Research Publications (IJSRP), 11(9), 132-138. https://doi.org/10.29322/IJSRP.11.09.2021.p11717 DOI: https://doi.org/10.29322/IJSRP.11.09.2021.p11717

Evarist, C., Luvara, V. G. M., & Chileshe, N. (2023). Perception on constraining factors impacting recruitment and selection practices of building contractors in Dar Es Salaam, Tanzania. International Journal of Construction Management, 23(12), 2012-2023. https://doi.org/10.1080/15623599.2022.2031556 DOI: https://doi.org/10.1080/15623599.2022.2031556

Fama, E., & Jensen, M. (2015). Agency problems and residual claims. 58(2), 325-355.

Giménez, J., Madrid-Guijarro, A., & Duréndez, A. (2019). Competitive Capabilities for the Innovation and Performance of Spanish Construction Companies. Sustainability, 11(19), 5475. https://doi.org/10.3390/su11195475 DOI: https://doi.org/10.3390/su11195475

Hendrastuti, R., & Harahap, R. F. (2023). Agency theory: Review of the theory and current research. Jurnal Akuntansi Aktual, 10(1), 85. https://doi.org/10.17977/um004v10i12023p085 DOI: https://doi.org/10.17977/um004v10i12023p085

Israel, B. (2023). The impact of clients' procurement challenges on the substance goals of roads construction projects in Songwe, Tanzania. International Journal of Construction Management, 23(12), 2144-2150. https://doi.org/10.1080/15623599.2022.2045861 DOI: https://doi.org/10.1080/15623599.2022.2045861

Kimzanye, L. (2021). Assessment of the Quality of Road Construction Projects Conducted by Tarura: A Case of Kinondoni District [Thesis in Project Management, Open University of Tanzania]. https://repository.out.ac.tz/

Kothari, C. R., & Garg, G. (2013). Research methodology: Methods and techniques (3. ed). New Age International Publ.

Kumar, R., Tiwari, P., & Singh, V. (2018). Quality assurance and control in road construction: Best practices. 16(7), 983-994. https://doi.org/10.1007/s40999-018-0245-z.

Masengesho, E., Wei, J., Niyirora, R., & Umubyeyi, N. (2021). Relationship between Project Consultants' Performance and Project Success in the Rwandan Construction Industry. World Journal of Engineering and Technology, 09(01), 138-154. https://doi.org/10.4236/wjet.2021.91011 DOI: https://doi.org/10.4236/wjet.2021.91011

Mersni, H., & Can, G. (2022). The Moderator Effect of Institutional Ownership on the Relationship between Cash Holdings of Life-Cycle Stages: Evidence from Borsa Istanbul. Business and Economics Research Journal, 3. https://doi.org/10.20409/berj.2022.381 DOI: https://doi.org/10.20409/berj.2022.381

Niazi, G. A., & Painting, N. (2017). Significant Factors Causing Cost Overruns in the Construction Industry in Afghanistan. Procedia Engineering, 182, 510-517. https://doi.org/10.1016/j.proeng.2017.03.145 DOI: https://doi.org/10.1016/j.proeng.2017.03.145

Njeri, D., & Were, S. (2019). Determinants of project performance in non-governmental organizations in Kenya, a case study of hand in hand Eastern Africa. 1(4), 61-79.

Nyakala, K. S., Pretorius, J.-H., & Vermeulen, A. (2019). Factor analysis of quality assurance practices in small and medium-sized road-construction projects: A South African perspective. Acta Structilia, 26(1), 1-41. https://doi.org/10.18820/24150487/as26i1.1 DOI: https://doi.org/10.18820/24150487/as26i1.1

Pace, D. (2021). Probability and Non-Probability Sampling-An Entry Point for Undergraduate Researchers. Sampling Procedure, 9(2), 1-15.

Pallant, J. (2020). SPSS survival manual: A step by step guide to data analysis using IBM SPSS (Seventh edition). Routledge.

https://doi.org/10.4324/9781003117407 DOI: https://doi.org/10.4324/9781003117407

https://doi.org/10.4324/9781003117452 DOI: https://doi.org/10.4324/9781003117452

https://doi.org/10.4324/9781003117445 DOI: https://doi.org/10.4324/9781003117445

Park, K., & Kim, B. (2024). Effects of Individual Client's Competencies on Construction Project Performance: Mediating Participation Attitude and Partnership. 14(3), 40.

https://doi.org/10.3390/admsci14030040 DOI: https://doi.org/10.3390/admsci14030040

Ridder, H.-G. (2017). The theory contribution of case study research designs. Business Research, 10(2), 281-305. https://doi.org/10.1007/s40685-017-0045-z DOI: https://doi.org/10.1007/s40685-017-0045-z

Siayor, B. (2020). Assessment of the Effectiveness of Quality Management Practices in Management of Reinforced Concrete Structures in Ghana. [A Thesis submitted to the Department of Construction Technology and Management, Kwame Nkrumah university of Science and Technology]. https://ir.knust.edu.gh/server/api/core/bitstreams/6bfa2403-08a4-4321-87ee-1d5fe24d3817/content

Singh, S., & Tiwari, R. K. (2020). Quality of service-based service selection in smart parking. International Journal of Information and Decision Sciences, 12(2), 154. https://doi.org/10.1504/IJIDS.2020.106722 DOI: https://doi.org/10.1504/IJIDS.2020.106722

United Nations Habitat. (2022). Urban development and infrastructure challenges: The case of Dar es Salaam. https://unhabitat.org.

Vargas-Hernández, J. G., & Teodoro Cruz, M. E. (2018). Corporate governance and agency theory: Megacable case. Corporate Governance and Sustainability Review, 2(1), 59-69. https://doi.org/10.22495/cgsrv2i1p5 DOI: https://doi.org/10.22495/cgsrv2i1p5

Velumani, P., Nampoothiri, N. V. N., & Urbański, M. (2021). A Comparative Study of Models for the Construction Duration Prediction in Highway Road Projects of India. Sustainability, 13(8), 4552. https://doi.org/10.3390/su13084552 DOI: https://doi.org/10.3390/su13084552

Widhiadnyana, I. K., & Dwi Ratnadi, N. M. (2019). The impact of managerial ownership, institutional ownership, proportion of independent commissioner, and intellectual capital on financial distress. Journal of Economics, Business, & Accountancy Ventura, 21(3), 351-360. https://doi.org/10.14414/jebav.v21i3.1233 DOI: https://doi.org/10.14414/jebav.v21i3.1233

World Bank. (2019). Infrastructure for development: Road networks and their impact. World Bank Group.

Published

2025-04-25

How to Cite

Juma, J. R., & Nsimbila, P. (2025). The Influence of Quality Control Mechanism Implemented by Consultants on Quality Assurance of Road Projects: A Case of Dar es Salaam Metropolitan Development Projects, Tanzania. African Journal of Empirical Research, 6(2), 241–251. https://doi.org/10.51867/ajernet.6.2.22

Issue

Vol. 6 No. 2 (2025): Apr-Jun 2025

Section

Articles
Copyright & Licensing

Copyright (c) 2025 Juma Ramadhani Juma, Paul Nsimbila

Creative Commons License

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

Crossref
Scopus
Google Scholar
Europe PMC