After grouting the ducts in a large band beam and one-way slab post-tensioned floor system in a large shopping mall （in excess of 1.5 km2 in plan）, doubts arose concerning the level of initial prestress and the stre...After grouting the ducts in a large band beam and one-way slab post-tensioned floor system in a large shopping mall （in excess of 1.5 km2 in plan）, doubts arose concerning the level of initial prestress and the strength and serviceability of the slabs was questioned. To assess the strength of the slabs, it was assumed, as a worst case scenario, that some spans may have been constructed with zero initial prestress. Load tests on prototype specimens, with similar dimensions and reinforcement quantities as the floor slabs, were performed to assess the stress development in initially unstressed, but fully grouted, tendons. Unexpected bond failures occurred at the junctions of slab and band beam where the abrupt change in section depth caused a sudden change in tendon stress. The maximum stress that was developed in the initially unstressed tendons at these locations was about 60% of the strength of the tendons.展开更多
Mega shopping mall projects have seen dramatic growth and great development in recent years in Egypt. Many new mega shopping mall projects are under construction and expecting to start working in the few coming years....Mega shopping mall projects have seen dramatic growth and great development in recent years in Egypt. Many new mega shopping mall projects are under construction and expecting to start working in the few coming years. In the absence of researches studying the Egyptian mega shopping mall projects, this study tries to highlight the most critical risks that face these projects and the associated most effective response methods to be employed. The scope covers the analysis from different perspectives by including owners/developers, designers, consultants, project managers, and contractors that have previous experience in large-scale projects such as shopping mall projects. In this study, 30 construction project risks are classified into six main categories according to their type and 150 risk mitigation/elimination measures are introduced to overcome the impact of risks under each of these risk categories. The results reveal that the main risk category that faces the mega shopping mall projects in Egypt is the one including the financial risk factors. The most critical risk factor that faces these projects is the financial ability of the client. These results are similar to findings by previous researches conducted for large projects in other countries.展开更多
文摘After grouting the ducts in a large band beam and one-way slab post-tensioned floor system in a large shopping mall （in excess of 1.5 km2 in plan）, doubts arose concerning the level of initial prestress and the strength and serviceability of the slabs was questioned. To assess the strength of the slabs, it was assumed, as a worst case scenario, that some spans may have been constructed with zero initial prestress. Load tests on prototype specimens, with similar dimensions and reinforcement quantities as the floor slabs, were performed to assess the stress development in initially unstressed, but fully grouted, tendons. Unexpected bond failures occurred at the junctions of slab and band beam where the abrupt change in section depth caused a sudden change in tendon stress. The maximum stress that was developed in the initially unstressed tendons at these locations was about 60% of the strength of the tendons.
文摘Mega shopping mall projects have seen dramatic growth and great development in recent years in Egypt. Many new mega shopping mall projects are under construction and expecting to start working in the few coming years. In the absence of researches studying the Egyptian mega shopping mall projects, this study tries to highlight the most critical risks that face these projects and the associated most effective response methods to be employed. The scope covers the analysis from different perspectives by including owners/developers, designers, consultants, project managers, and contractors that have previous experience in large-scale projects such as shopping mall projects. In this study, 30 construction project risks are classified into six main categories according to their type and 150 risk mitigation/elimination measures are introduced to overcome the impact of risks under each of these risk categories. The results reveal that the main risk category that faces the mega shopping mall projects in Egypt is the one including the financial risk factors. The most critical risk factor that faces these projects is the financial ability of the client. These results are similar to findings by previous researches conducted for large projects in other countries.
