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The fuselage riveted lap-joints are susceptible to multiple site damage (MSD) and should be considered in damage tolerance analysis. This paper aims to investigate the stress intensity factor (SIF) and crack growth simulation for lap-joints based on three-dimensional (3D) finite element analysis.

The 3D finite element model of lap-joints is established by detailed representation of rivets and considering the rivet clamping force and friction. Numerical study is conducted to investigate the SIF distribution along the thickness direction and the effect of clamping force. A predictive method for the cracks propagation of MSD is then developed, in which an integral mean is adopted to quantify the SIF at crack tips, and the crack closure effect is considered. For comparison, a fatigue test of a lap-joint with MSD cracks is conducted to determine the cracks growth live and measure the cracks growth.

The numerical study shows that the through-thickness crack at riveted hole in lap-joints can be treated as mode I crack. The distribution of SIF along the thickness direction is inconstant and nonmonotonic. Besides, the increase in clamping force will lead to more frictional load transfer at the faying surfaces. The multiple crack growth simulation results agreed well with the experimental data.

The novelty of this work is that the SIF distribution along the thickness direction and the MSD cracks growth simulation for lap-joints are investigated by 3D finite element analysis, which can reflect the secondary bending, rivet clamping, contact and friction in lap-joints.

The purpose of this paper is to address the specific challenges with which resource‐based cities are faced when they begin along the path of industrial transformation and to employ empirical studies to determine whether relevant reforms in resource‐based cities (taking Pingxiang, one of the first round of resource‐exhausted cities acting as pilot cities in the national sustainable development transformation program, as an example), promoted by local government in recent years, have brought significant changes to their development modes and facilitated the real transition.

The paper carried out some empirical studies from different angles: employing the “vertical table graph” method, to turn Pingxiang's statistical data (1997‐2010) into a graph that visually shows Pingxiang's economic and social development; comparing several major economic and social development indicators (especially the energy consumption per unit of GDP) of 11 cities within Jiangxi Province in order to learn Pingxiang's relative positions; based on time series data from 1997 to 2009, calculating the change rates, the variation coefficients and the shift‐share indexes of industrial structure so as to measure the quality of Pingxiang's structural transformation; comparing the above results with the cities of Jiaozuo, Benxi and Dalian; and comparing economic and social development state of 16 resource‐based cities (which are all among the list of 44 national resource‐exhausted cities) from the perspective of “green GDP”.

Although Pingxiang has gained great progress in economic development, its industrial structure is not rational enough, and shows great dependence on mining industry with a too high share of the secondary industry and a too small proportion of the tertiary industry. Its heavy dependence on resources and investment does not suggest a fundamental change in development modes. Accordingly, the city's development idea should be switched from GDP‐orientation to sustainable development. It should proceed with the optimization of the industrial structure adjustment, increase manpower capital investment and develop new green substitutable industries, so as to catalyze the success of transition.

This integration of empirical analysis methods from three angles in multivariate statistical analysis, environmental economics, and industrial economics is novel in the field of research on resource‐city and industry change. It not only could be of some help in decision making for Pingxiang municipal government, but also could provide reference for other cities dependent on resource exploitation.

This study aims to investigate the effect of countersunk rivet head dimensions on the fatigue performance of the riveted specimens of 2024-T3 alloy.

The relationship between rivet head dimensions and fatigue behavior was investigated by finite element method and fatigue test. The fatigue fracture of the specimens was analyzed by scanning electron microscopy.

A change of the rivet head dimensions will cause a change in the stress concentration and residual normal stress, the stress concentration near the rivet hole causes the fatigue crack source to be located on the straight section of the countersunk rivet hole and the residual normal stress can effectively restrain the initiation and expansion of fatigue cracks. The fatigue cycle will cause the rivet holes to produce different degrees of surface wear.

The fatigue life of the specimens with the height of the rivet head of 2.28 mm and 2.00 mm are similar, but the specimens with the height of the rivet head of 1.72 mm were far higher than the other specimens.

The purpose of this study is to investigate the microstructure of fretting wear behavior in 6061-T6 aluminum alloy. The fretting wear of blind riveted lap joints of 6061-T6 aluminum alloy plates, which are widely used in aircraft construction, was investigated. Fretting damages were investigated between the contact surface of the plates and between the plate and the rivet contact surface.

Experiments were carried out using a computer controlled Instron testing machine with 200 kN static and 100 kN dynamic load capacity. Max package computer program was used for the control of the experiments. Fretting scars, width of wear scars, microstructure was investigated by metallographic techniques and scanning electron microscopy.

It was found that fretting damages were occurred between the plates contacting surface and between the plate and rivet contact surface. As load and cycles increased, fretting scars increased. Fretting wear initially begins with metal-to-metal contact. Then, the formed metallic wear particles are hardened by oxidation. These hard particles spread between surfaces, causing three-body fretting wear. Fretting wear surface width increases with increasing load and number of cycles.

The useful life of many tribological joints is limited by wear or deterioration of the fretting components due to fretting by oscillating relative displacements of the friction surfaces. Such displacements are caused by vibrations, reciprocating motion, periodic bending or twisting of the mating component, etc. Fretting also tangibly reduces the surface layer quality and produces increased surface roughness, micropits, subsurface microphone.