Data/hora: 20/06/2024 23:41:10

Biblioteca(s): 	Embrapa Cerrados; Embrapa Meio Norte / UEP-Parnaíba.	
Data corrente: 	14/03/1996	
Data da última atualização: 	14/10/2002	
Autoria: 	REIS, A. E. G. dos.	
Título: 	Effect of cohesive forces on the critical gradient.	
Ano de publicação: 	1977	
Fonte/Imprenta: 	Davis: University of California, 1977.	
Páginas: 	99p.	
Idioma: 	Inglês	
Notas: 	PhD. Dissertation.	
Conteúdo: 	The problem of sedimentation into subsurface drains has received much attention from those  interested in designing gravel envelopes. Materials such as fine sand coarse silt are extremely susceptible to a "quick condition". Thus, it is a well-known practice to base the design criteria of gravel envelopes on considerations of grain-size curves. However, this may result in uneconomical approach when the same design is used for cohesive soils. The design should account for the hydrodynamic seepage forces causing movement of the soil particles, as well as the cohesive forces  that operate at the contact of the particulate arrangement of the base material. Here I will examine the above mentioned aspects. It is my purpose to determine the effectiveness of parameterssuch as cohesive forces in foundations as vectors opposing the hydrodynamic forces that cause a "quick condition". A general study will attempt to analyze the possible mechanisms involved in the phenomenon of susceptibility to piping or tunneling, and of the movement of fines  into subsurface drains. An investigation of the cohesive and adhesive forces that add to the  critical gradient of a given base material may help improve the design and installation of agricultural drain pipes or drains placed under hydraulic structures. 	
Thesagro: 	Drenagem; Propriedade Mecânica; Solo.	
Thesaurus Nal: 	drainage.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Cerrados (CPAC)	
Exemplares: 	CPAMN-UEPP - (5289-1) - ADD - TS - PP - TS 013/1977 -  - TS013/1977 - DIS
CPAC - (22031-1) - ADD - TS - -- - T078/77 - REI - T078/77 - DIS