Public and Private Construction Projects in Tabriz Experience Divergent Delay Patterns

In municipal environments characterized by complex administrative procedures and divided operational responsibilities, construction schedule overruns stem from distinct systemic pressures depending on project ownership, according to an investigation of urban construction projects in Tabriz, Iran. Published in Discover Civil Engineering by researchers Ali Zamanfar and Hooman Sobouti, the study analyzed the structural mechanisms that disrupt project delivery schedules across government projects and non-government developments. Although both sectors operate within the same municipal territory and share an overarching legal environment, the empirical findings demonstrate that public sector initiatives experience more severe overall delays governed by external administrative constraints, procurement bottlenecks, and supervisory deficiencies, whereas private developments encounter disruptions centered primarily around internal financial instability, aggressive bidding strategies, and operational execution bottlenecks. By comparing both governance regimes within a single urban center, the authors isolated sector-specific mechanisms from broader national, macroeconomic, or regional disparities.

Understanding schedule disruptions in urban construction has historically relied on cross-country factor evaluations or aggregated national surveys, which often conflate broad economic instability with institutional decision-making structures. In urban settings, construction and infrastructure developments operate under concentrated administrative, regulatory, and physical conditions encompassing residential, commercial, municipal, and public-service undertakings. These projects inherently exhibit heightened stakeholder interdependence, tighter regulatory oversight, and direct vulnerability to local municipal governance. Prior investigations frequently ranked isolated delay drivers without establishing theoretical explanations for why equivalent stakeholder groups generate divergent delay outcomes across different organizational arrangements. To address these analytical gaps, the researchers framed their inquiry around institutional theory and project governance theory, examining how formal statutory mandates, administrative accountability channels, procurement mechanisms, and supervisory authority interact with informal professional norms to shape schedule performance under identical municipal rules in Tabriz.

The study evaluated delay factors organized across five primary dimensions: laws and regulations, client-related factors, consultant-related factors, contractor-related factors, and city-specific contextual conditions. To identify and structure these variables, the authors conducted a systematic literature review covering both international and domestic project management research, mapping identified variables directly to established governance frameworks. This preliminary inventory was subsequently evaluated and refined through an expert validation phase involving academic specialists, experienced engineering consultants, and senior civil engineers familiar with the operating realities of Tabriz. Measurement of the resulting factors relied on a five-point Likert scale ranging from one, denoting very low impact, to five, denoting very high impact. To ensure instrument integrity, internal reliability was evaluated using Cronbach’s alpha coefficients across each category, all of which exceeded the standard 0.70 benchmark, while the overall survey instrument achieved a composite alpha reliability score of 0.92.

Data collection utilized a purposive expert sampling strategy focused on qualified practitioners with extensive operational familiarity with local construction delivery systems. The target population was derived from the professional registry of the Tabriz Construction Engineering Organization, which maintains an active membership of approximately 20,000 to 25,000 registered professionals. To maximize evaluation quality and minimize uninformed responses, participation was strictly limited to registered civil engineers who possessed more than fifteen years of direct professional experience across government or non-government urban building works. A total of 1,512 structured questionnaires were distributed to qualifying professionals, yielding 1,250 complete and validated survey responses after rigorous screening for completeness and consistency, representing an effective response rate of 82.7 percent. The authors maintained respondent anonymity throughout the survey process to mitigate social desirability bias and encourage objective professional appraisals across both public and private sector projects.

To evaluate the ordinal survey data without making unsupported assumptions regarding data normality, the research design prioritized non-parametric statistical techniques alongside supplementary parametric comparisons. Descriptive metrics, including means, standard deviations, and mean rank orders, summarized perceived factor impacts across both sectors. The Friedman test was applied independently within the government and non-government project groups to assess relative rank differences among related factor clusters evaluated by the same respondents. For between-sector comparisons across the five categories, the Mann-Whitney U test served as the primary non-parametric inferential technique, supplemented by rank-biserial correlations to quantify effect sizes, while independent-samples t-tests and Cohen’s d statistics provided secondary parametric checks. All statistical evaluations established significance at a probability threshold of p less than 0.05, establishing a methodologically conservative analytical baseline for evaluating perceived operational and regulatory bottlenecks.

The overarching category evaluations revealed substantial structural divergences between sectors, as contractor-related challenges ranked as the foremost delay source in government projects, while client-related factors emerged as the leading impediment within non-government projects. Statistically significant sectoral differences emerged specifically across contractor-related and regulatory-related categories, underscoring the disproportionate burden that formal administrative procedures and procurement mechanisms impose on public works. Within the regulatory dimension, the Friedman test identified significant internal ranking variations in both sectors (p less than 0.001), with the inappropriate implementation of modern Engineering, Procurement, and Construction (EPC and EP) contracts rated as the most critical common regulatory issue. However, delayed issuance of administrative directives and circulars ranked second in government projects and showed a statistically significant elevation compared to the private sector (p = 0.011), reflecting the operational inertia generated by multi-layered institutional approvals and rigid bureaucratic oversight.

Client-related dynamics similarly highlighted how governance mandates distort operational performance between public agencies and private developers. In government projects, excessive emphasis on lowest-bid tender selection ranked as the primary client-related cause of delay, closely followed by inadequate initial budget allocations and systemic funding delays. Comparative testing verified that lowest-bid selection protocols were significantly more damaging in government developments (p = 0.027), accompanied by significantly higher rates of client interference in consultant duties (p = 0.018) and prolonged delays in physical land acquisition and site benchmark delivery (p = 0.011). In sharp contrast, non-government projects ranked capital shortages and delayed milestone payments as their primary client-related obstacles, followed by inadequate preliminary budget planning and compressed project planning durations. These variations demonstrate that while public projects suffer from rigid administrative mandates and inter-agency handover frictions, private ventures remain directly exposed to market-driven liquidity shortages, cash flow volatility, and investment-related uncertainties.

Assessments of consultant and contractor performance revealed corresponding divergences in technical and managerial execution. Among consultant-related factors, the Friedman test demonstrated significant internal differences (p less than 0.001) for both groups, with government projects identifying weak conflict identification and a deficit of administrative management personnel as top concerns, whereas non-government projects cited reliance on traditional techniques, absence of creative problem-solving, and insufficient supervisory technical knowledge. The reliance on reactive, trial-and-error execution methods was significantly higher in government projects (p = 0.019). In contractor evaluations, contractor financial weakness ranked first in government projects, exhibiting a statistically significant difference compared to private works (p = 0.037), where inappropriate bid pricing and executive management deficiencies dominated. This indicates that lowest-bid public procurement frequently selects undercapitalized contracting firms that struggle with cash flow under delayed government disbursements, whereas private contractors adopt aggressive underbidding to win contracts, undermining subsequent site execution.

The evaluation of municipal and city-specific conditions illustrated that broader urban governance arrangements independently govern construction timeliness outside project boundaries. In government works, inadequate construction supervision, insufficient project funding, and weak stakeholder coordination constituted the highest-ranked city-level factors. Non-government developments identified cumbersome municipal bureaucracy as their primary city-specific delay driver, alongside weak stakeholder collaboration and supervisory limitations. Mann-Whitney comparisons showed that government projects experienced significantly worse disruptions from inadequate supervision (p less than 0.001), limited capability among local contracting firms (p = 0.001), weak coordination among participating stakeholders (p = 0.005), external non-project issues (p = 0.032), and the deployment of non-local consulting and contracting firms (p = 0.038). Despite these sector-specific variations, poor inter-stakeholder coordination and systemic planning and control deficiencies were identified across both sectors as persistent, shared drivers of project schedule inflation throughout Tabriz.

While providing comparative clarity, the authors highlighted several methodological limitations inherent to the study design. Because the findings rely on cross-sectional survey data collected from 1,250 registered engineering professionals, the recorded scores reflect subjective expert perceptions rather than direct, measured project timelines or archival audit data. Furthermore, conducting the investigation exclusively within the municipal boundaries of Tabriz limits immediate generalizability to alternate urban environments that possess different institutional arrangements, administrative resources, or economic frameworks. The quantitative survey approach demonstrates statistical associations and relative factor prioritizations rather than establishing definitive causal mechanisms among governance variables. Consequently, the researchers recommend that future inquiries incorporate longitudinal tracking of physical project durations across multiple metropolitan regions, coupled with qualitative case studies, regression models, and structural equation modeling to rigorously map the causal interactions linking institutional governance, procurement practices, and urban construction schedule overruns.

Subject of Research: Comparative analysis of urban construction delay factors across government and non-government sectors in Tabriz

Article Title: Explaining and comparing delay patterns in urban construction projects across government and non-government sectors in Tabriz

Article References: Zamanfar, A., & Sobouti, H. (2026). Explaining and comparing delay patterns in urban construction projects across government and non-government sectors in Tabriz. Discover Civil Engineering, 3(1), Article 240. https://doi.org/10.1007/s44290-026-00644-2

Image Credits: AI Generated

DOI: 10.1007/s44290-026-00644-2

Keywords: construction project delays, urban construction management, government construction projects, non-government construction projects, Tabriz civil engineering, contractor financial weakness, procurement practices, EPC contracts, administrative bureaucracy, Friedman test, Mann-Whitney U test, Tabriz Construction Engineering Organization, project governance, stakeholder coordination, schedule overrun, client-related delay factors, consultant supervision, lowest-bid procurement