Analysis of photovoltaic-green roofs in OSTIM industrial zone

In the current century, climate change, air pollution, and the depletion of energy resources are big threats to our society, especially in urban areas. It is an inevitable fact that we need to develop the green building concept and produce innovative solutions in our quest to design structures that are compatible with nature, sustainable, environmentally friendly, aesthetic and use natural resources efficiently. Roofs are the most efficient and promising building surfaces for the combination of photovoltaic panel applications and green roofs considering their locations and inclination angles. This research focuses on how carbon emission can be reduced via both green roofs and solar energy while producing electricity in OSTIM, one of Turkey's most prominent industrial zones located in the capital. The long-term detailed analysis of photovoltaic-green roof application in terms of economics and carbon emission is discussed. Although the rooftop option of a combination of solar panels and a green roof design costs higher than a standard photovoltaic system, it opens up new prospects for urban lighting in smart cities with exciting aesthetic effects. This combination of two sustainable features can become a model of green technology and opens up a wide range of research applications.     

Performance of AC overlays using geogrids on PCC contraction joints

It is widely known that vertical displacements and strains occur on the joints and these cause defects on the asphalt concrete (AC) overlays on existing Portland cement concrete (PCC) pavements. Various approaches were introduced to minimize these defects. In this study, the effect of joint support formed using the geogrid material with grout mortar on the vertical displacement of PCC and the strain at the bottom of the AC layer. Produced layers were exposed to 1,186,000 Equivalent Single Axle Load (ESAL) in an APT (Accelerated Pavement Test) facility and the results were monitored. According to the obtained results, the use of AC overlay reduces vertical displacement in the PCC by 75%. When geogrid reinforced AC overlay was used, an additional reduction in displacement by 41.2% was achieved. Geogrid reinforcement reduced strain values formed at the bottom of the AC layer from 29.5% to 92.5%. The use of geogrid at joints instead of increasing the thickness of the AC layer from 50 to 80 mm resulted a more significant reduction in both strain and displacement. Besides, the usage of a geogrid interlayer instead of increasing the thickness of the AC layer also provided a significant cost reduction of 57.9% in overall cost.