GONZAGA, E.; GONZAGA, Espedito.
Resumo:
The results of a study of the applicability of the PVC tube as a non-conventional
drain are presented in this work. Three tubes with diameters 50, 75 and 100 mm using
opening areas of 16 and 23cm2/m were tested under controlled conditions in tanks filled
with sand. Standard corrugated tubes of TUPY (TUPY-DRENO) and DRENOFLEX
(TIGRE) with 65 and 110 mm diameter were used as reference tubes. The study
applicability of the effective use of the non-conventional material based on the
evaluation of the performance of the different drainage systems as a function of the
following parameters: entrance and total hydraulic head losses; entrance resistance;
resistance factor; and the effective diameter. The criteria adapted for the evaluation o f
the systems took into account the suggestion of DIELEMAN & TRAFFORD (1976)
and WESSELING & V A N SOMEREN (1972). From the view point of hydraulic head
losses, the non-conventional systems and the reference standard were considered
moderate to good. Acording to the entrance resistance all the systems tested were
considered good. The systems performed satisfactorily within the range when the
resistance factor was taken into account. The effective diameters, obtained for the
non-conventional tubes, showed that the increase in diameter had little influence on the
effective diameter while the increase in entrance area resulted in increased effectiv
diameter. The effective diameters obtained from the standard reference tubes were
almost three times those of non-conventional tubes. It is observed that the standard
reference tubes were superior (in performance) in relation to non-conventional tubes.
Probably as a consequence of better geometry of openings and perfuration for the entry
of water. I t suggests that other studies related to the non-conventional material, with
different opening geometries and envelops should be realized at the prototype level as
well as at the field level.
