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Structural design theory and method for the polyurea coating system have rarely been developed. The normally used experience-based design method may lead to unsafe, unreasonable and uneconomic results. The purpose of this paper is to investigate the deformation and failure behaviour of the polyurea coating so as to propose a rational design method.

In this study, the fundamental theories concerning the nonlinear analysis of polyurea coating were discussed. Nonlinear Finite Element Method (FEM) models were built to investigate the mechanical behaviour, peeling behaviour and failure mode of the polyurea coating under various conditions, such as surface fracturing, surface hydraulic pressure and reverse hydraulic peeling.

The main conclusions are as follows. The peeled coating at the crack location exhibits a tensile-bending stress state. Coating material damage may occur at the stress concentration point. The maximum stress increases with the increase in the hydraulic pressure and cohesive strength. The peeling length of the coating decreases with the increase in cohesive strength and increases with the increase in fracture width. The reverse hydraulic pressure-induced blister edge stress concentration is the main trigger of the polyurea coating blistering damage. The blistering height decreases with increasing coating thickness and increases with increasing blistering radius and hydraulic load. The maximum stress increases with increasing blistering radius and hydraulic load. Finally, the frame of design and simple design programme were proposed.

Currently, a design method for polyurea anti-seepage coating can hardly be found. The reason is that the anti-seepage coating has only been recognized as a water-proofing layer, the mechanical behaviour of which has been ignored. This study focused on the mechanical behaviour of the anti-seepage coating and investigated the deformation and failure behaviour of the coating structure under various loading conditions through nonlinear FEM analysis. These research results offer a better understanding concerning the mechanical behaviour and design method of the polyurea anti-seepage coating.

Multilayer composite liner structures are the primary structural form of hydraulic tunnels. However, the bearing mechanism of multilayer composite liners has not been investigated thoroughly. Many existing design schemes do not properly achieve a balance between structural safety, anti-seepage capacity, and cost effectiveness. Thus, a new composite liner structure type and its theoretical model was proposed.

A novel hydraulic tunnel composite liner structure with a polyurea spray coating interlayer was proposed in this study. A theoretical model based on the state-space method was developed and verified using FEM models and existing theoretical models. Parametric analysis was conducted based on the theoretical model to investigate the influence of various variables, including interfacial shear stiffness, inner liner thickness, and outer liner elastic modulus.

It was concluded that the proposed theoretical model can be used successfully to calculate multilayer composite liner structures with high calculation efficiency. The overall deformation stiffness of the composite liner system increased with the interfacial shear stiffness. The sprayed coating interlayer significantly affects the residual force distribution between the outer and inner liners, which can also be affected by the adjustment of the thickness of the outer and inner liners. Thus, attention should be paid to these factors in the rational design of the proposed composite liner system.

With the development of China’s water conservancy projects, complex geological conditions, high surrounding rock stress, high internal and external water pressures, and other unique application scenarios have gradually increased. This places higher requirements on the bearing performance and impermeability of hydraulic tunnel lining structures. On the other hand, conventional hydraulic tunnel lining structures can hardly achieve a satisfactory balance between economy, structural safety, and impermeability. Thus, the proposed structure has the potential to be used in a wide range of applications.

The behavior of joints has a significant effect on the stability of water conveyance tunnel. The purpose of this paper is to study the contact and friction at the joint of the tunneling segment lining and establish its contact friction model. At the same time, the stress and deformation characteristics at the joint of the segment under hydrostatic load are analyzed.

In this study, the contact and friction in a bolted joint are examined using shear testing. The feasibility of the proposed model is verified by a numerical simulation of tests and a theoretical analysis. Accordingly, the effect of joints on the lining is explored under internal hydrostatic loading.

The results show that the openings of tunnel segments in joints gradually expand from the positions of the inner and outer edges to the location of the bolt. Moreover, the stress concentration zone is formed at the bolt. Under hydraulic loading, the opening displacement at the joint increases as the water pressure increases; nevertheless, it does not exceed engineering requirements. When the water pressure of the tunnel lining joint reaches 0.5 MPa, the opening of the joint slowly increases. When the water pressure exceeds 0.7 MPa, the opening of the joint rapidly and significantly increases.

Contact and friction in a bolted joint were examined using shear testing. A cohesive zone model of bolted joints was proposed based on test results. The influence of joint behavior on the stability of water conveyance tunnel was studied.

College students' employment is a significant problem in the process of China's economic development. Owing to the comprehensive effect, entrepreneurship has become the important way to solve the problem of university students' employment. The purpose of this paper is to analyze systematically the main difficulties of university students' entrepreneurship in China and present corresponding policy recommendations.

This paper takes the conceptual analysis approach. Referring to the Nyawali and Fogel model of 1994, the paper constructs the key‐determinant model of China's university students' entrepreneurship and analyzes and explains the situation by adopting existing statistics and survey data about China's university students' entrepreneurship.

After the global financial crisis, encouraging university graduates' entrepreneurship to create more employment opportunities has become the key strategy to deal with employment problems for China's government. This paper finds that, although the university students have some advantages, there are still several difficulties for university graduates' entrepreneurship. Effective countermeasures must be taken to strengthen the entrepreneurship capacity by enhancing entrepreneurship education, increasing entrepreneurship opportunities by improving the entrepreneurship environment and raising the entrepreneurship desire by perfecting financing system and then encouraging university graduates to start up businesses actively, so that more college students could become entrepreneurs.

This paper systematically constructs the key‐determinant model of China's university students' entrepreneurship. The policy recommendations for college students' entrepreneurship presented in this paper might be referred to by government to make decisions to improve university students' entrepreneurship support policy and enhance university students' entrepreneurship ability.

Purpose – This chapter examines the challenges in exploring, analysing and developing the concept of social capital, seen as the proclivity (or otherwise) of societies to engender stable structures for cooperativeness that support economic exchange and control. The authors focus on Asia and outline a theory of researchable social capital elements. Methodology is considered against the contexts of Asia. The authors emphasize the role of higher education as determinant, seeing it as crucial to the accumulation of human capital and often at the centre of many theories of societal progress.

Findings – The authors’ findings are that social capital is a contested concept that does not rest within a bed of widely adopted theory; researching it comparatively requires acknowledging societal meaning structures; there is emerging acceptance of complexity theory, evolutionary dynamics, and multi-disciplinary analysis; it is possible to disaggregate the concept into researchable issues; many research methods are available.

Implications – Modes of human cooperativeness are crucial for the understanding and comparison of economic systems. Implications are strong and pervasive for policy and practice. The authors find no evidence of a distinct indigenous ‘Asian’ perspective in research but much evidence of powerful contributions from Asian scholars working collaboratively with colleagues internationally.

Originality/Value – The chapter provides a helicopter perspective of an emerging field, notes conceptual challenges and gives practical guidance for researchers.