علا حسين عبدالمطلب خان

Hollow concrete block has become a popular option nowadays in building activities where these blocks offer different benefits: economy, stability, and strength, simplicity in utilization in building elements. In this study the effect of different air gap configurations within the hollow concrete block was investigated, both circular ,elliptical and rectangular shape configuration where used by assuring all to have the same air volume within air gap of (0.0025 m3).The process of manufacture of hollow concrete blocks performed according to Iraqi standard (IQS1077). Both mechanical ,thermal insulation and acoustic insulation properties where measured and studied for the three configurations, for mechanical properties is compressive strength test where used according to ASTM A4-1985 and it found that the result of circular ,elliptical and rectangular is (16.30,7.06,10.87 Mpa) respectively ,while for thermal properties a single heat source for 2.4 Kw at different distance (25cm,50cm,75cm and 1m) where used in order to measure the effect of configuration of thermal insulation and it found that the circular gives best results of thermal insulation. Acoustic properties compacted at different frequency value at (250,500,1000 Hz) in order to measure the acoustic insulation for each configuration and it found the circular give the best result.