El drenaje subterraneo en las carreteras

Subdrainage in roads

El efecto del agua en el firme es perjudicial, por lo que debe ser evacuada a traves de los sistemas de drenaje superficial, transversal y subterraneo. Debe conocerse tanto su procedencia como su caudal, asi como el marco geografico en que se encuentra. Los efectos desfavorables son multiples: arrastre y expulsion de finos, acelerando el fallo estructural de la calzada y acortando su vida util. Se debe estimar el caudal, tanto del que proviene del firme como del que accede por el terreno natural. La que procede del firme, depende del grado de conservacion y fisuracion del mismo. El principal elemento drenante del firme es la capa de subbase, y el principal medio drenante del agua que proviene del terreno son las zanjas drenantes, tanto longitudinales como transversales. Se fijan criterios para el dimensionamiento de la subbase, dependiendo del sistema de drenaje elegido: vertical, lateral o combinado, teniendo en cuenta la permeabilidad de la explanada. Para el buen funcionamiento de la red de drenaje se requiere una adecuada capa drenante bajo el pavimento, una pendiente adecuada de la explanada y una buena red de evacuacion del agua. El uso de las zanjas drenantes, no solo se debe contemplar como interceptacion del agua sino tambien como evacuacion de la misma (zanja colectora). Por ultimo, se contempla el uso de materiales geotextiles debido a su durabilidad, evitando que las capas drenantes se colmaten y pierdan su funcionalidad. (A). English abstract: Water has a damaging effect on road pavements and therefore needs to be evacuated through surface, transverse and underground drainage systems. It is important to know where the water comes from and its volume of flow, as also the geographical context involved. The adverse effects are numerous - entrainment and expulsion of fines, accelerating structural failure in pavements and shortening their useful life. Flow is estimated from both the water stemming from pavements and from the natural ground in the vicinity. Pavement accumulated water depends on the degree of maintenance and cracking involved. The major drainage element in a pavement is its sub-base layer while the major drainage medium for ground water consists of both longitudinal and transverse drainage ditches. The criteria set for sizing the sub-base depend on whether the drainage system chosen is vertical, lateral or a combination of the two and its design takes into account the permeability of the subgrade. For the drainage system to be effective an adequate drainage layer needs to be provided under the pavement, the subgrade needs to have an acceptable gradient and a good evacuation network is required for the water. The use of drainage ditches should not only be studied from the point of view of cutting off water but also for evacuation purposes (collector ditch). Finally, the article discusses the use of geotextiles owing to their durability and ability to prevent drainage layers clogging up and losing their functions. (A).

Language

  • Spanish

Media Info

Subject/Index Terms

Filing Info

  • Accession Number: 01183092
  • Record Type: Publication
  • Source Agency: Centro de Estudios y Experimentación de Obras Públicas (CEDEX)
  • Files: ITRD
  • Created Date: Oct 7 2010 11:11AM