Unbalanced bidding has presented a significant issue in the construction industry. The award of a contract to an unbalanced bid poses a significant threat to the construction cost, as well as construction activities. The nature of an unbalanced bid, irrespective of the form, consists of quotations higher or lower than the reasonable unit price. In this paper, the engineer’s estimated price was chosen as the evaluation criterion. Consequently, a model was developed in order to identify unbalanced bids based on unascertained model. The unbalanced bid can be identified, which provides useful inputs for bid evaluation. As a result, unbalanced bids can be prevented. The feasibility of the method was verified via a case study. The method proposed in this paper facilitates an effective and efficient quantitative assessment of unbalanced bids. This model not only assists owners in effectively and efficiently identifying unbalanced bids, but also discourages bidders from unbalancing their bids.

Engineering, procurement, and construction (EPC) has been applied in China’s hydropower projects for its value-added advantages compared with traditional project delivery systems in theory. However, the actual performance of large EPC hydropower projects has been challenged by the complexity of the stakeholders’ interest demands and conflicts. The increasing use of target cost contracts (TCC) in the construction industry has provided a pain/gain share mechanism for the owners to incentivize contractors to complete projects within cost budgets. The added-value sharing ratio is the core element of TCC, and it predetermines how much proportion of savings the contractor can get paid if the actual cost is below the target cost, and how much proportion of overspend the contractor has to pay if the actual cost is higher than the target cost. In this paper, we consider the added-value sharing ratio under the framework of TCC based on the principal-agent theory, and look at how the added-value sharing ratio is influenced by various factors and how it affects the owner and the contractor in large EPC hydropower projects. Determination of the added-value sharing ratio in both discrete and continuous conditions are discussed, respectively. It is found that the added-value sharing ratio is relatively explicit in the discrete case, while the optimal added-value sharing model in the continuous case is more complex, which can be used to analyze the relationship between the added-value sharing ratio and the key influencing factors. Our research conclusions can provide both theoretical guidance and practical suggestions to contract design in the implementation of EPC hydropower projects, to some extent.

A large‐scale engineering procurement and construction (EPC) project is often conducted by a joint venture. Many factors affect the success of cooperation among participating enterprises, such as trust and the degree of effort of both parties. The most important one is a rational profit sharing mechanism. Reasonable profit sharing mechanism concerns whether the advantages of the EPC model can be fully utilized. In this study, the proposed EPC project is undertaken by a joint venture integrating design and construction enterprises. Moreover, the profit sharing problem arises from the project optimization implemented by both parties. The fairness concern behavior of both parties is considered, and the profit sharing model for the EPC project is established on the basis of game theory. The effect of the fairness concern behavior of both parties on the EPC project optimization and its profit sharing is further analyzed by simulation analysis. The research findings show that the project optimization profit and its sharing are related to not only the efforts and cost coefficient but also the fairness concern behavior of both parties. The research results are conducive to the application of the EPC model in the field of construction engineering.

Project delivery system (PDS) is critical to the success of a construction project. There is a strong link between contract type and project delivery method. Therefore, this paper presents a framework for multiobjective decision-making that combines project delivery method and contract type for the first time. Furthermore, the Pythagorean fuzzy set (PFS) is introduced in the decision-making model. A new method for PDS group decision-making is constructed by combining PFS with the entropy weighting method and prospect theory. In order to improve the reliability of decision-making, this paper proposes a new method for determining decision-maker weights based on comprehensive weights, which is used to distinguish the professional level of decision-makers. Finally, the PDS decision-making process is elaborated through case analysis, the effectiveness of the decision-making model is verified, and the differences between the PDS decision-making method and the traditional method are discussed, which proves the reliability of the method. The method proposed in this paper can provide support for the owners PDS selection.

Urban water ecological civilized construction is an important measure for relieving contradiction between water and people and building a harmonious city. It is also a necessary measure to improve the environment and life quality in cities. The evaluation of current urban water ecological civilized construction and construction effect is an important part in the urban water ecological civilized construction. At present, few research into the water ecological civilized construction has been conducted at home. And, the evaluation system for the construction is incomplete. In this study, an evaluation model of current urban water ecological civilized construction is proposed by using the fuzzy material-element theory. The results demonstrate it is a robust method for evaluating urban water ecological civilized construction.

Water and soil resources (WSRs) determine the healthy development of the socio-economic systems. This research seeks to clarify the spatiotemporal evolution characteristics, spatial spillover effects, and key constraint factors influencing the comprehensive carrying capacity (CCC) of WSR in the Yellow River (YR) Basin from 2012 to 2023, thereby supporting the healthy development of the river basin. Based on the structural relationships among the internal elements of this system, the entropy method and an extensible cloud model are employed in this study to evaluate the WSR-CCC. Based on the estimation theory and spatial econometrics methods, the temporal and spatial evolution process of WSR-CCC was explored, and the obstructive factors were analyzed. We made the following discoveries: (1) The WSR-CCC demonstrates a fluctuating upward tendency, gradually moving from critical overload level IV to sustainable level II, but inter-provincial disparities expand. (2) The spatial pattern exhibits a gradient of higher levels in the western region, lower levels in the eastern region, stronger intensity in the northern region, and weaker intensity in the southern region, with weak spatial correlation. However, the spatial spillover effect is significant, with club convergence and the Matthew effect coexisting. (3) The obstacle factors exhibit a drive–influence–state three-stage dominant characteristic. The findings provide actionable insights for coordinating WSR optimization and ecological conservation.