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The purpose of this paper is to improve the reliability of the force measurement system by determining the reliable test range of dynamometer.

Based on the principle of leverage and moment balance, a general force distribution model is applicable in where the test point is located either inside or outside the support region of four three-component force links of dynamometer is established. After corroborating the correctness of the model through verification experiments, the boundary conditions that each three-component force link should satisfy are analyzed by considering the characteristic of the dynamometer components comprehensively. Furthermore, the reliable test range of dynamometer is determined, followed by a calibration experiment to verify its rationality.

The relationships between the reliable test range and the tested force, the bolt pre-tightening force and the bearing capacity of quartz wafers are clarified. Further, the experimental calibration results show that when the test point is within the reliable test range, the three-directional output voltage of dynamometer has excellent linearity and repeatability. The nonlinearity and repeatability in X-, Y- and Z-directions are all less than 1.1%.

A general mathematical model of force distribution of four three-component force links is constructed, which provides a theoretical basic for the mechanical analysis of multi-sensors’ dynamometer. Comprehensively considering the performance of dynamometer components, the value of measured force and the pre-tightening force, the simultaneous equations of reliable test range are deduced, which limits the boundary of allowable test position of piezoelectric dynamometer.

While existing literature emphasizes the importance of empowerment in construction projects, the working mechanisms of empowering leadership in the project context are unclear. Based on conservation of resources (COR) theory, this study aimed to examine the relationship between empowering leadership and project performance, highlighting the mediation roles of creative self-efficacy and leadermember exchange and the moderation role of perceived overqualification.

The authors collected data from 287 project members in different projects and tested the integrated conceptual model through moderated mediation analysis with bootstrapping strategy.

The results revealed that empowering leadership was positively related to project performance through creative self-efficacy and leader–member exchange. Perceived overqualification served as significant moderator.

The findings contribute to the understanding of empowering leadership in projects by verifying and extending the resource acquisition and investment process in the project context. The results of this study also demonstrated that creative belief and social exchange facilitate the effectiveness of project members' task efforts and outcomes and that perceived overqualification might not exert a detrimental effect on project performance.