الفهرس 
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Abstract
The test results of the current experimental program showed that the developed ferrocement beams with openings and reinforced with innovative reinforcing materials achieved high strength, better deformation characteristics, crack resistance, high ductility and energy absorption properties. Irrespective of the type and number of steel mesh layers and number of openings had better mechanical properties than conventional reinforced concrete beams.
The results also demonstrated that ferrocement concrete beams with openings showed fine crack widths at failure without spalling of concrete cover that is predominant. Within the scope, parameters, theoretical and analytical investigation considered in this research and based on the test results and observations of the experimental investigation; the following conclusions and recommendations may be drawn as follows: 1. Saving in the total reinforcing steel weight ranging could be achieved by utilizing welded galvanized steel mesh, expanded metal mesh and 120 Chapter 6 Conclusions and Recommendations for future works fiber glass mesh for durability reason. The saving in the steel weight ranged from 20% to 30%.
2. The beams incorporating ferrocement forms and high strength mortar matrix achieved higher first crack load, serviceability load, ultimate load, and energy absorption compared to the control test specimen irrespective of the type of steel mesh and number of steel mesh layers.
3. Beam B5 with two openings at both ends of the beam and reinforced with four layers of galvanized welded steel mesh and steel bras without using stirrups, volume fraction of reinforcing materials, 2.862% showed the high ductility ratio, 15.385 of all the tested beams.
4. Beam B6 with two openings at both ends of the beam and reinforced with one layer of expanded metal mesh and steel bras without using stirrups, volume fraction of reinforcing materials, 2.756% showed the energy absorption, 638.15 KN.mm of all the tested beams.
5. Increasing the number of the steel mesh layers in the ferrocement forms increases the first crack load, service load, ultimate load, and energy absorption. On the other hand it decreases the ductility of the beam.
6. Employing steel mesh in reinforcing concrete beams with openings, irrespective of the type of steel mesh and numbers of openings is significant in strengthening the matrix surrounding the openings and 121 Chapter 6 Conclusions and Recommendations for future works consequently improving strength, deformation characteristics and cracking behavior with great saving of reinforcement.
7. All tested beams with openings reinforced with various types of steel meshes showed at failure cracking control without spalling of concrete cover that is predominant due to the result of reducing stress concentration around the openings.
8. The theoretical methods for first crack and ultimate load calculations provide good prediction for these loads and the beam’s mode of failure.
9. The developed beams utilizing beams with openings reinforced with innovative reinforcing materials could be successfully used as an alternative to the traditional reinforced concrete beams, which can be of true merit in both developed and developing countries besides its anticipated economic and durability merits. Further research needs to be conducted to reach sound recommendations for practical use especially for the beams provided with four and five openings. 6.2 Recommendations 1.
To study the viability of employing other types of mesh reinforcement in the ferrocement forms such as polypropylene mesh and tesar mesh. 122The test results of the current experimental program showed that the developed ferrocement beams with openings and reinforced with innovative reinforcing materials achieved high strength, better deformation characteristics, crack resistance, high ductility and energy absorption properties. Irrespective of the type and number of steel mesh layers and number of openings had better mechanical properties than conventional reinforced concrete beams.
The results also demonstrated that ferrocement concrete beams with openings showed fine crack widths at failure without spalling of concrete cover that is predominant. Within the scope, parameters, theoretical and analytical investigation considered in this research and based on the test results and observations of the experimental investigation; the following conclusions and recommendations may be drawn as follows:
1. Saving in the total reinforcing steel weight ranging could be achieved by utilizing welded galvanized steel mesh, expanded metal mesh and 120 Chapter 6 Conclusions and Recommendations for future works fiber glass mesh for durability reason. The saving in the steel weight ranged from 20% to 30%.
2. The beams incorporating ferrocement forms and high strength mortar matrix achieved higher first crack load, serviceability load, ultimate load, and energy absorption compared to the control test specimen irrespective of the type of steel mesh and number of steel mesh layers.
3. Beam B5 with two openings at both ends of the beam and reinforced with four layers of galvanized welded steel mesh and steel bras without using stirrups, volume fraction of reinforcing materials,
2.862% showed the high ductility ratio, 15.385 of all the tested beams.
4. Beam B6 with two openings at both ends of the beam and reinforced
with one layer of expanded metal mesh and steel bras without using
stirrups, volume fraction of reinforcing materials, 2.756% showed the
energy absorption, 638.15 KN.mm of all the tested beams.
5. Increasing the number of the steel mesh layers in the ferrocement
forms increases the first crack load, service load, ultimate load, and
energy absorption. On the other hand it decreases the ductility of the beam.
6. Employing steel mesh in reinforcing concrete beams with openings, irrespective of the type of steel mesh and numbers of openings is
significant in strengthening the matrix surrounding the openings and 121 Chapter 6 Conclusions and Recommendations for future works consequently improving strength, deformation characteristics and cracking behavior with great saving of reinforcement.
7. All. tested beams with openings reinforced with various types of steel meshes showed at failure cracking control without spalling of concrete cover that is predominant due to the result of reducing stress concentration around the openings.
8. The theoretical methods for first crack and ultimate load calculations provide good prediction for these loads and the beam’s mode of failure.
9. The developed beams utilizing beams with openings reinforced with innovative reinforcing materials could be successfully used as an alternative to the traditional reinforced concrete beams, which can be of true merit in both developed and developing countries besides its
anticipated economic and durability merits. Further research needs to
be conducted to reach sound recommendations for practical use
especially for the beams provided with four and five openings.
6.2 Recommendations
1. To study the viability of employing other types of mesh reinforcement
in the ferrocement forms such as polypropylene mesh and tesar mesh.
122The test results of the current experimental program showed that the
developed ferrocement beams with openings and reinforced with
innovative reinforcing materials achieved high strength, better
deformation characteristics, crack resistance, high ductility and energy
absorption properties. Irrespective of the type and number of steel mesh
layers and number of openings had better mechanical properties than
conventional reinforced concrete beams. The results also demonstrated
that ferrocement concrete beams with openings showed fine crack widths
at failure without spalling of concrete cover that is predominant.
Within the scope, parameters, theoretical and analytical investigation
considered in this research and based on the test results and observations
of the experimental investigation; the following conclusions and
recommendations may be drawn as follows:
1. Saving in the total reinforcing steel weight ranging could be achieved
by utilizing welded galvanized steel mesh, expanded metal mesh and
120
Chapter 6 Conclusions and Recommendations for future works
fiber glass mesh for durability reason. The saving in the steel weight
ranged from 20% to 30%.
2. The beams incorporating ferrocement forms and high strength mortar
matrix achieved higher first crack load, serviceability load, ultimate
load, and energy absorption compared to the control test specimen
irrespective of the type of steel mesh and number of steel mesh layers.
3. Beam B5 with two openings at both ends of the beam and reinforced
with four layers of galvanized welded steel mesh and steel bras
without using stirrups, volume fraction of reinforcing materials,
2.862% showed the high ductility ratio, 15.385 of all the tested beams.
4. Beam B6 with two openings at both ends of the beam and reinforced
with one layer of expanded metal mesh and steel bras without using
stirrups, volume fraction of reinforcing materials, 2.756% showed the
energy absorption, 638.15 KN.mm of all the tested beams.
5. Increasing the number of the steel mesh layers in the ferrocement
forms increases the first crack load, service load, ultimate load, and
energy absorption. On the other hand it decreases the ductility of the
beam.
6. Employing steel mesh in reinforcing concrete beams with openings,
irrespective of the type of steel mesh and numbers of openings is
significant in strengthening the matrix surrounding the openings and
121
Chapter 6 Conclusions and Recommendations for future works
consequently improving strength, deformation characteristics and
cracking behavior with great saving of reinforcement.
7. All. tested beams with openings reinforced with various types of steel
meshes showed at failure cracking control without spalling of concrete
cover that is predominant due to the result of reducing stress
concentration around the openings.
8. The theoretical methods for first crack and ultimate load calculations
provide good prediction for these loads and the beam’s mode of
failure.
9. The developed beams utilizing beams with openings reinforced with
innovative reinforcing materials could be successfully used as an
alternative to the traditional reinforced concrete beams, which can be
of true merit in both developed and developing countries besides its
anticipated economic and durability merits. Further research needs to
be conducted to reach sound recommendations for practical use
especially for the beams provided with four and five openings.
6.2 Recommendations
1. To study the viability of employing other types of mesh reinforcement
in the ferrocement forms such as polypropylene mesh and tesar mesh.