000			02907cam a2200337 a 4500
003			EG-GiCUC
005			20250223032653.0
008			210110s2020 ua dho f m 000 0 eng d
040			_aEG-GiCUC _beng _cEG-GiCUC
041	0		_aeng
049			_aDeposite
097			_aM.Sc
099			_aCai01.13.05.M.Sc.2020.Om.A
100	0		_aOmar Badr Mohamed Badr
245	1	0	_aAppropriate drain envelope for problematic calcareous soils in Egypt / _cOmar Badr Mohamed Badr ; Supervised Abdallah S. Bazaraa , Gehan A.H. Sallam
246	1	5	_aاختيار مغلف مواسير الصرف المناسب للتربات الكلسية الاشكالية بمصر
260			_aCairo : _bOmar Badr Mohamed Badr , _c2020
300			_a101 P . : _bcharts , facsmilies , photographs ; _c30cm
502			_aThesis (M.Sc.) - Cairo University - Faculty of Engineering - Department of Civil Engineering
520			_aAgricultural subsurface drainage systems are commonly used to remove the excess water and salts from the root zone to enhance crop production and to ensure irrigated agriculture sustainability. In Egypt, drain pipes installed in soils with limited cohesion (clay content is less than 30%) should be provided with envelopes to prevent the entry of soil particles into the drains (filter function) and to reduce entrance resistance by creating a more permeable zone around drains (hydraulic function). Calcareous soils with calcium carbonate (CaCO3) content of more than 15% are considered hazardous problematic soils that cause envelope clogging and sedimentation in the subsurface drainage network. Earlier testing of synthetic drain envelopes in Egyptian calcareous soils has revealed poor performance. Therefore, the main objective of this study is to determine the most appropriate locally available envelope material(s) that can be used in calcareous soils under Egyptian conditions. Both theoretical and experimental (laboratory as well as field) investigations were conducted to assess the performance of the locally available synthetic envelope (polypropylene with pore size 400 microns {u2013} PP400) alone and combined with granular materials. The assessment results (theoretical and experimental) indicated that the currently used synthetic envelope PP400 is not performing well when used alone (too thin with low porosity). Treatments that have a gravel material, either alone or in combination with the locally available synthetic envelope revealed good performance and consequently gravel envelopes alone are recommended
530			_aIssued also as CD
653		4	_aCalcareous soils
653		4	_aEnvelope materials
653		4	_aSubsurface drainage
700	0		_aAbdallah S. Bazaraa , _eSupervisor
700	0		_aGehan A.H. Sallam , _eSupervisor
856			_uhttp://172.23.153.220/th.pdf
905			_aAmira _eCataloger
905			_aNazla _eRevisor
942			_2ddc _cTH
999			_c79514 _d79514