الفهرس 
AcknowledgmentOnly 14 pages are availabe for public view
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Abstract
The modern methods of construction are used widely at the last decades in the construction field. Some of these
methods are slipform, tunnel form, precast units etc.
Such methods require special properties for their concretes.
this study discribes some of these methods and the properties of concretes. It was noticed that, the construc¬tion by slipforming heeds special requests of concretes
properties, specially in hot climate areas. Also, predec
tion of friction forces between the concrete and the form is
not found. This predection helps in determining the number and capacity of hydraulic jacks. Uptill now such determina¬tion depends solely on experience.
An experimental program of two parts has been done; the first part studies the effect of several factors on the properties of slipform concrete. Some of these factors are: degree of temperature, time of mixing and dosage of admix¬ture. This part is devoted to choose the best ways to con¬trol the workability of concrete under different conditions. Also to show how to minimize the losses of slump during transportation of concrete from the central mixers to the sites. It is recommended to add the used admixture (retarder-plastisizer) in two increments. This admixture is very important during transportation specially in high tem¬peratures. These data are represented in collective curves