Chapter 1: Utilization of paper sludge ash in lime based geopolymer concrete: -an experimental study.- Chapter 2: Influence of Two Discrete Heaters on the Laminar Natural Convection Inside a Closed Room.- Chapter 3: Disruption of Construction Industry during COVID-19 pandemic - A case study from Ernakulam, Kerala, India.- Chapter 4: 3D-FE Analysis of RC Tunnel with GFRP Shielding under Internal Blast Loading.