الفهرس | Only 14 pages are availabe for public view |
Abstract Ferrocement is defined as ‘A thin walled construction, consisting of rich cement mortar with uniformly distributed and closely spaced layers of continuous and relatively small diameter mesh (metallic or other suitable material). It is always a challenge to estimate the force on ferrocement subjected to DROP weight impact and due to the importance of impacts and impulsive loads, such as those occurring inaccidental conditions (i): rock fall on a shelter, vehicles or ships in collision with buildings, bridges or offshore infrastructures .The main objective of this research is to study the impact resistance of reinforced ferrocement plates . Research divided to three parts. first part , five mixes were carried out to select suitable mix and satisfy the requirements of research .second part eleven ferrocement plates were designed and cast with dimensions of (500 × 500×25 mm),The ferrocement plates were reinforced with welded, expanded, tensar metal mesh, with steel bars. All test specimens were tested under impact load until failure. The impact test was carried out by released a 3.100kg steel ball from a height of 1125mm (1.125m) to the center surface of the plate (specimen). This process was repeated until failure of the plate. The total number of bows (impact) which caused the appearance of the first visible crack(s) and failure of the plate were noted. This procedure was repeated for all the rest of the plates. Third part , plates rehabitated by two layer welded mesh at two faces and by special mortar . Plates tested again under impact load. Results of reinforced ferrocement plates emphasized that increasing the number of the steel mesh layers in the ferrocement forms increases the first crack load, number of blows to failure and energy absorption. Using steel bars with steel meshes led to higher energy absorption than that obtained when using mild steel bars only. Using rubber and fiber achieved high impact energy .The existence of the fibres and rubber in the mortar mix resulted in an increase in the first crack, failure load , controlling crack width , and impact energy absorption. Adding rubber to mortar mix decreased the loss of weight of plates. Ferrocement plates were developed with high strength and energy absorption properties which could be useful for developed and developing countries alike. |