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As a crucial measure to promote the coordinated development of urban and rural areas in developing countries (such as China), how to provide and manage rural infrastructure investment is a major challenge. In line with the implementation of a coordinated urban–rural development strategy, inclusive growth provides direction for rural infrastructure investment. Taking Chongqing, China, as an example, informed by the goals of inclusive growth, this study develops a system dynamics model to investigate the interaction between interdependent infrastructure systems and socioeconomic systems and to explore priorities for rural infrastructure investment. The results indicate the following: (1) more rural infrastructure investment is still needed in Chongqing by 2030; and (2) based on the importance of all types of rural infrastructures for the impact of inclusive growth goals, the ratio of budget shares invested in each dimension is, in descending order, environment infrastructure, energy infrastructure, communication infrastructure, transportation infrastructure, education infrastructure, and medical infrastructure. The approach and results of this study allow governments to assess the contribution of infrastructure provision to the goals of inclusive growth and to make better-informed infrastructure investment options. [ABSTRACT FROM AUTHOR]

Major civil and military infrastructures are usually located in mountainous areas with complex geological structures. When subjected to impact loads caused by operational blasting or seismic activities, the inherent flaws or joints in the hosting rock mass may grow irreversibly and eventually and cause the entire structure to collapse. It is, therefore, desirable to understand the mechanical and cracking behaviors of flawed rock structures under dynamic loads. In this work, the cement mortar is used to make the plate specimens, and two different types of flaws, i.e., the open and the closed (resin-filled) flaws, with different inclination angles from 0° to 90° with respect to the loading direction are prefabricated. The nominal strength, crack initiation, and failure characteristics of the specimens under different loading rates are investigated using the split Hopkinson bar (SHPB) system in conjunction with the digital image correlation (DIC) technique. The results indicate that the dynamic nominal strength of both two types of specimens shows similar loading rate and flaw angle dependency, specifically, monotonically increasing with the increase of the loading rate while increasing first and then decreasing with increasing the flaw inclination angle. The strength of specimens with an open flaw is obviously lower than that of the specimens with a closed flaw at a similar loading rate. Besides, the failure mode of specimens with an open flaw is mainly an X-shaped tensile or tensile-shear mixed form regardless of the flaw inclination, whereas the resin-filled flawed specimens always fail in the form of an atypical X-shaped shear pattern with obvious randomness. Moreover, the stress field around the crack tip is carefully extracted based on the obtained displacement field from DIC analysis; the stress intensity factors at crack initiation onset also show flaw inclination- and loading rate-dependent behavior. The strength, cracking behavior, and stress field around the tip during the dynamic loading are closely related to the friction effect between the flaw surfaces. The findings in this work provide some basic insights into the cracking mechanism of rock with open and closed flaws under dynamic loading conditions. [ABSTRACT FROM AUTHOR]

Purpose: With the growing demand for infrastructure and public services in recent years, PPP-UP have attracted a great deal of attention. However, while the user focuses on the payment for use and the private sector is concerned with its return on investment, the public sector pays more attention to the efficient utilization of public funds. In order to analyze the willingness of each stakeholder to join PPP-UP, an evolutionary game model involving the three parties is constructed. Design/methodology/approach: An evolutionary game model is established that considers the users and the public and private sectors in user-pay public-private-partnership projects (PPP-UP). Eight scenarios of equilibriums and the game's evolutionary stable strategies are analyzed, and the corresponding stability conditions are then obtained. A situation where all three players are willing to cooperate in theory is also examined. The key influencing parameters that affect cooperation behaviors are further discussed. Findings: First, the results illustrate that by properly adjusting the influencing factors, the cooperation status among the three parties can be changed along with certain evolutionary trends. Second, it is hard to modify unsatisfactory evolutionary stability by small changes in both the price compensation of and the construction and operation compensation. Third, it is necessary to involve the users in the decision-making process in PPP-UP and take their demands regarding benefits and payments into account. Originality/value: In this paper, we focus on PPP-UP to research interactions among the public and private sectors and the users. Based on the analysis of the evolutionary game, to facilitate the successful implementation and development of a project, several conditions are needed to ensure tripartite cooperation. Several recommendations are then proposed for decision-makers in PPP-UP. [ABSTRACT FROM AUTHOR]