SEIR model and simulation research on unsafe psychological state propagation of construction workers considering safety climate and intimate relationships.

The construction industry is a pillar industry of China and occupies an essential position in our economic development. However, in the fast-developing construction industry, the number of its safety accidents is also growing year by year. Safety accidents are often due to unsafe behaviors of construction workers, and unsafe precarious psychological states are important factors for unsafe behaviors. Therefore, this paper, based on a review of existing literature, uses the SEIR model and numerical simulation method to study the spread of unsafe psychological states among construction workers considering safety climate and intimate relationships. It puts forward corresponding countermeasures, which has great practical significance for reducing safety accidents in the construction industry. The results show that: (1) A good safety climate can help alleviate the spread of unsafe psychological states of construction workers. (2) The intimate relationship between construction workers will promote the association between communicable people and susceptible people, which will lead to the spread of an unsafe psychological state. (3) A larger network average degree will increase the spread speed and the density of communicable people, but will not increase the spread range.(4) Forgetting rate has a key role in the propagation of unsafe psychological states. Suggestions are made to hinder the propagation of these states, which will help to reduce the unsafe behavior of construction workers and the accident rate in the construction industry.

Evolutionary Game and Simulation of Green Housing Market Subject Behavior in China.

In China, driven by the national "3060" double carbon targets (i.e., reaching peak carbon emissions by 2030 and carbon neutrality by 2060), green housing has become one of the major fields to reduce carbon emissions, facilitating the achievement of the double carbon targets. Promoting the growth of green housing is an important way for the real estate industry to achieve low-carbon transformation and improve the quality of housing. Meanwhile, the construction industry also can benefit from green housing to achieve its energy conservation and emission reduction targets. Therefore, it is critical to boost and maintain the sustainable growth of the green housing market in China. However, the literature has not focused attention on the market behavior of the green housing market in China. This study proposes a tripartite evolutionary game model to investigate the subject behavior of the green housing market in China. This model consists of three major subjects in a green housing market: developers, consumers, and governments. Based on this model, this study analyzes the stability of the strategy options for each stakeholder and identifies the stable conditions of strategy portfolios to reach the equilibrium points of the game system. The validity of the proposed tripartite evolutionary game model is tested through the simulation of the impacts from various factors on system evolution. According to the impacts of factors and the stable conditions of strategies, this paper puts forward relevant policy suggestions for the healthy and sustainable growth of China's green housing market.

A system dynamic model for simulating the potential of prefabrication on construction waste reduction.

Prefabrication is a promising method for minimizing construction waste since it is conducted in a controlled environment. This paper develops a simulation model for quantitatively evaluating the potential of prefabrication on construction waste reduction by considering interaction behaviors among factors influencing the application of prefabrication and construction waste reduction during the design stage. The theory of planned behavior is applied to determine the system boundary, and a system dynamic model is applied for establishing the simulation model. A case project in Anhui, China, is selected for demonstrating the established model. Results show that the (1) Application of prefabrication method contributes to construction waste reduction by reducing material wastes and reworking due to design changes. (2) Impacts of prefabrication method on concrete waste reduction is the most significant. (3) Increasing investment on designers' professional training and strengthening policies is two efficient strategies to make full use of the potential of the prefabrication method on construction waste reduction during the design stage. The developed model can offer designers as well as policymakers with references for applying prefabrication method for construction waste reduction by comparing outcomes under various scenarios with different strategies and policies ahead of implementation.