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• A innovative and efficient model was proposed for multi-lane highway. • The learning was collected a lot of existed pavement segments and built a large-scale highway network. • The LCA and LCCA was integrated to assess the sustainability of the M&R decision. • GDE3 performs well in selecting more cost-effective M&R optimization. A pavement maintenance and rehabilitation decision-making model plays a significant role in the sustainable development of highway networks. However, various maintenance and rehabilitation models lack the capacity to provide multi-objective maintenance decision-making strategies, which are solely concerned with reducing maintenance costs. This study aims to propose a multi-objective maintenance decision-making model, called the Pavement Maintenance-Generalized Differential Evolution 3 (called PM-GDE3), by integrating the pavement condition indices and the generalized differential evolution 3 (GDE3) method. Economic aspect, pavement sustainability, and environmental dimensions were considered in the proposed model to increase the flexibility of pavement management. In this study, the widely-used PAVER maintenance system,which represents a conventional M&R decision-making model and the PM-GDE3 model were applied to estimate the optimal maintenance and rehabilitation schedules for the highway networks, and the results from these models were compared. The results show that the maintenance strategy obtained from the PM-GDE3 model maintains the highway in an acceptable condition. In addition, it has been found that the PM-GDE3 model saves 30.9% of maintenance expenses, about 169 million CNY, 16.9% of carbon emissions, around 4,469 kt, and 11.6% of energy consumption, 2.8GJ, for as long as 30 service years compared to the PAVER model. The PM-GDE3 model outperforms the widely used PAVER maintenance system due to its capacity to propose the optimal solution by establishing a real-time simulation with numerous pavement conditions after maintenance application. This field is the first attempt to combine pavement performance prediction model, life cycle assessment method and life cycle cost assessment. The achievements of the paper are expected to combat the impending energy crisis and climate change impacts of pavement maintenance and rehabilitation. [ABSTRACT FROM AUTHOR]

Climate changes and urban sprawl dramatically increase the urban temperatures and the thermal quality in the built environment. Among several proposed mitigation techniques, cool roofs have now reached a broad audience, while the cool materials potentialities for façade applications are still little investigated. A novel masonry paint, produced with the inclusion of cool pigments, is investigated in this paper. A palette of colour is developed with the objective of covering a wide range of architectural integration solutions. Reflectance and emissivity are measured and calculated. The results strongly depend on the base colour used to prepare the sample; solar reflectance increase up to 0.16 is achieved for dark colours. A numerical analysis is carried out to evaluate the impact of the cool paint on the thermal response of a typical Italian residential building. Energy uses are calculated for different insulation levels and climatic conditions. Cooling energy uses are reduced in the 10–20% range; total energy uses are affected by several parameters with 5% maximum savings. Peak operative temperature reductions range from 0.5 to 1.6 °C for the building in free floating conditions, according to climate and insulation level. External surface temperatures are reduced above 6 °C during the peak irradiation hours. [ABSTRACT FROM AUTHOR]

The building envelopes are exposed to the hot-humid climate with high humidity in hot summer and cold winter zone (HSCW) of China. The moisture transfer may severely influence the conduction loads through exterior walls. In this paper, a coupled heat and moisture transfer model is developed and validated to investigate the thermal performance of exterior walls. The conduction loads through a typical exterior wall are used to evaluate the effect of moisture transfer on the thermal performance of exterior walls in HSCW zone of China. The results show that the peak cooling and heating loads are overestimated by 2.1–3.9% and 4.2–10.1%, respectively, when ignoring moisture transfer. In cooling season, the sum of the latent load accounts for 14.3–52.2% of the sum of the total load and the yearly latent load accounts for 4.9–6.1% of the yearly total load when considering moisture transfer. The total cooling, heating and the yearly load are underestimated by 9.9–34.4%, 1.7–4.0%, and 5.2–6.8%, respectively, when ignoring moisture transfer. The results indicate that ignoring moisture transfer causes significant discrepancy in predicting the conduction loads. A detailed model considering moisture transfer in building envelope is essential to accurately evaluate the building energy performance in HSCW zone of China. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents the performance evaluation of a hybrid photovoltaic thermal (Semi transparent PVT) double pass facade for space heating. The thermal model has been developed by using the energy balance equations of the proposed hybrid photovoltaic thermal double pass facade under quasi-steady state condition. Numerical computations have been carried out for the composite climate of New Delhi, India. An analysis has been carried out to calculate annual energy and exergy gain for the hybrid photovoltaic thermal double pass facade. On the basis of numerical results it has been observed that the annual thermal and electrical energy are 480.81kWh and 469.87kWh respectively. The yearly overall thermal energy generated by the system has been calculated as 1729.84kWh. It is also observed that the room air temperature increases by 5–6°C than the ambient air temperature for a typical winter day. [Copyright &y& Elsevier]