الفهرس 
CHAPTER (1): INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
This thesis presents a new, effective and economic method for developing ferrocement shells. In this method, steel meshes were used as a viable alternative to ordinary conventional steel bars commonly used in reinforcing concrete shells. The proposed method is so simple that it dose not require neither complicated technology nor light-skilled labors. The results of both experimental and analytical investigation to examine the effectiveness of this method including the cracking patterns, characteristics, and strength characteristics of the tested shells are reported and discussed. To improve the properties of the mortar used in producing ferrocement shells, a study was conducted to examine the effect of silica fume on the properties of mortar and to determine its optimum percentage as a cement replacement. The results of this study are also presented and discussed.
Ten shells were cast and cured for 28-days before testing. The dimensions of all test specimens were kept constant. The length of the shell was 2000 mm, 1000 mm width and 40 mm thick but with different volume fractions of steel reinforcement. The Concrete shells and ferrocement shells reinforced with expanded metal mesh and welded steel mesh applying different reinforcement schemes. The reinforcement schemes included applying one layer of expanded metal mesh with ordinary steel bars, two and three layers of expanded metal meshes, three layers and six layers of expanded steel mesh.
The expermental steel mesh program consists of five series as follows
layers threeof , reinforced with sectionconsists of conventional reinforced :Series Asquare galvanized welded steel mesh.
f layers o sixconventional reinforced section, reinforced with consists of :Series Bsquare galvanized welded steel mesh.
expandedgalvanized layers of twowith consists of conventional reinforced :Series Csteel mesh with square opening
expandedgalvanized layers of threenventional reinforced with consists of co :Series Dsteel mesh.
With various steel meshes reinforcing of conventional reinforced materials, the specimens’ designations series were tested under the action of longitudinal line loadings.
nventional reinforcement steel bars.consists of co
:Series F With various types and layers of steel mesh reinforcement and filled with various types of concretes, mesh respectively.
A simple computer program was used to predict the behavior of these shells. The experimental results were used to verify the predicted results obtained using computer program.
The test results of the ferrocement mortar revealed that (10%) percent is the optimum replacement percentage of cement by silica fume for water/cement ratio of (0.30). The analytical and experimental results of reinforced ferrocement shells, better control of cracking behavior for all tested shells compared to control shells. Also it was found that the ultimate strength of the shells is affected by modified volume fraction. The ductility ratio and energy absorption properties of the tested shells were improved by this method of reinforcement. In general the experimental results proved the effectiveness of expanded metal mesh and welded steel mesh in reinforcing ferrocement shells. Ferrocement shells were developed with high strength, high ductility and energy absorption properties and lighter in weight, which could be useful for developed and developing countries alike.