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A permanent deformation model was developed in this study on the basis of shear properties of asphalt mixtures, such as cohesion and friction angle. Two types of laboratory tests—triaxial compressive strength test and repeated load permanent deformation test—for three types of asphalt mixtures with various volumetric properties were performed to correlate the shear properties with rutting performance. A rational approach was proposed to determine flow number (FN) more accurately with the Hoerl model and roughness penalty method. It was observed from the test results that the FN was not accurate enough to differentiate the rutting characteristics of asphalt mixtures. Unlike the FN, the shear stress to strength ratio accurately identified the mixture rutting performance. Because the same value of the shear stress to strength ratio produced the same level of permanent strain regardless of mixture type, the ratio could be used as the rutting criterion for a performance-based mix design. A permanent deformation model was established on the basis of the shear stress to strength ratio. The proposed model is able to successfully predict the permanent deformation of the various mixtures without changing the model coefficients and could predict the permanent deformation all the way up to failure, including the tertiary flow.

The injured central nervous system (CNS) can hardly regenerate. In vitro engineering of brain tissue hits technical bottlenecks. Also, the compaction and complexity of anatomical structure defy the accurate positioning for lesion sites in intracranial injuries. Therefore, repairing injured CNS remains a significant clinical challenge. Various recent in vivo and in vitro experiments have demonstrated the excellent effect of tissue engineering on repairing central nerve cells and tissues through implanting new materials and engineered cells. Except for porous three-dimensional structures able to pad lesions in various shapes and simulate the natural extracellular matrix with nutrients for cell proliferation, hydrogels incorporate high biocompatibility. Injectable hydrogels with the merits of avoiding complex surgery on large wounds, filling irregular gaps, delivering drugs, and others, are of growing interest. This review focuses on the experimental studies regarding injectable hydrogels, especially applying various injectable hydrogels to repair brain damage.

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Construction land reduction (CLR) is an important instrument for achieving environmental sustainability by reducing intensive land use, controlling the unrestrained extension of construction land and ensuring a balance between construction and arable lands in China. Existing studies on key factors of CLR projects are rare ， lacking comprehensive and systematic understanding. Key factors for ensuring the success of CLR projects have not been identified in previous studies. Based on a literature review and questionnaires, in this study, key success factors (KSFs) of CLR projects were identified and analysed. The Fuzzy-AHP and Fuzzy-DEMATEL methods were used to obtain the comprehensive causality and centrality values, whereby factors with a comprehensive causality value larger than 0 and a comprehensive centrality ranking in the top 20% were identified as KSFs. Results indicate that KSFs include the presence of a supportive policy for CLR, coordination with the original landowner, coordination with the surrounding residents, a diversity of enterprises participating in the CLR, a legal environment and land acceptance and testing standards. This paper lays a theoretical foundation for CLR projects and provides guidelines for achieving successful project implementations.