Engineering procurement and construction (EPC) is a normative practice globally approved since China has been engaging in international cooperation under the Belt and Road Initiative (BRI) infrastructure development. EPC has been adopted in the delivery of BRI infrastructure projects in other countries. Compared to the domestic method of contract, EPC remains at a low level in management practice, such as a lack of coordinating diverse project stakeholders, high cost of information communication, and risk in complex environments in West Asia (WA). However, no research has conducted a strategic analysis of the current situation of EPC for BRI infrastructure projects in West Asian countries. This study aims to understand the current status quo of EPC for BRI projects in WA by performing a strength, weakness, opportunity, and threats (SWOT) analysis and with the support of data collected from the literature review and semi-structured interviews with EPC stakeholders. The study brings awareness along which internally and externally circumstances of the EPC for BRI infrastructure projects can be perceived by major stakeholders participating. The four critical strategies presented based on the SWOTs identified could help EPC firms develop and promote EPC to implement BRI infrastructure projects in WA at the strategic level.

Since the Belt and Road Initiative (BRI) has been put in practice by the Chinese government, several High-Speed Railways (HSR) have been built by Chinese Engineering Procurement and Construction (EPC) firms. However, many delays have created severe detrimental consequences on the progress of most HSR projects. This study sought to explore the essence of the recurring triggers of delays in international EPC HSR projects under the BRI, and a structured questionnaire survey approach was applied to compile the first-hand dataset from Chinese EPC firms working for BRI infrastructure projects. The data were evaluated, and the Relative Importance Index (RII) was adopted to assess the magnitude of the important delay triggers. The findings suggest that HSR projects are still susceptible to unavoidable delays in global construction infrastructure projects. In the engineering phase, improper management of the design, unsustainable land acquisition, and insufficient use of EPC joint venture are the salient trigger of delays. In the procurement phase, the leading causes of unsuitable procurement, undervalued procurement cost, inefficient logistics in labor and materials, improper planning, unqualified site supervisors, inefficient technical standard management, and inefficient constant payment terms are likely to trigger delays in the construction phase HSR projects. Five critical groups of delay factors are identified by this study, which has an essential primary contribution to the body of knowledge and is helpful to EPC contractors working for HSR projects under BRI.

Warm-mix asphalt technology has been applied to recycled rubber asphalt binder (RAB), which forms warm-mixed crumb rubber-modified asphalt binder (W-RAB) as a “green” material for environmental conservation and to enhance road performance. Furthermore, low-temperature cracking is one of the major distresses for asphalt pavement, which drastically restricts ride quality and service level. Therefore, the main objective of this study is to comparatively analyze the low-temperature properties of W-RABs based on thermal stress and the simple fractional model. W-RABs were obtained by mixing 60 mesh recycled rubber (CR) and two different types of warm-mix additives, namely viscosity reducer (1, 2, and 3%) and surfactant (0.4, 0.6, and 0.8%). First, Hopkins and Hamming’s numerical algorithm and the Boltzmann superposition principle were used for obtaining thermal stress $\sigma \left(T\right)$. Subsequently, critical cracking temperature $T_{cr}$ was derived using the single asymptote procedure (SAP) theory. Second, the simple fractional viscoelasticity model was used to calculate the creep compliance, damping ratio, and dissipation energy ratio, and the results were compared with the Superpave protocol results obtained with bending beam rheometer (BBR) tests. The results showed that a combination of CR and warm-mix additives could slightly improve the thermal crack resistance of the asphalt binder. The addition of 0.6% surfactant yielded the optimum performance, while only a high dosage (3%) of viscosity reducer provided a marked improvement in efficiency, which decreased with a decrease in temperature. This study recommends the use of RAB composited with 0.6% surfactant for areas with extremely low temperature.

This paper is intended to introduce a two-stage detection method to solve the multidamage problem in bridges. Vibration analysis is conducted to acquire the dynamic fingerprints which are regarded as information sources. Bayesian fusion is used to integrate these sources and preliminarily locate the damage. Then, the RSNB method which combines rough set theory and Naive-Bayes classifier is proposed to simplify the sample dimensions and fuse the remaining attributes for damage extent detection. A numerical simulation of a real structure, the Sishui Bridge in Shenyang, China, is conducted to validate the effectiveness of the proposed detection method. Data fusion based method is compared with single-valued index method at the damage localization stage. The proposed RSNB method is compared with the Back Propagation Neural Network (BPNN) method at the damage qualification stage. The results show that the proposed two-stage damage detection method has better performances in regard to transparency, accuracy, efficiency, noise robustness, and stability. Furthermore, an ambient excitation modal test was carried out on the bridge to obtain the vibration responses and assess the damage condition with the proposed method. This novel approach is applicable for early damage detection and provides a basis for bridge management and maintenance.