Zastosowanie metod geofizycznych przy rozpoznawaniu wałów przeciwpowodziowych w świetle wyników prac eksperymentalnych

Abstract

GEOLOGICAL METHODS IN RECOGNITION OF FLOOD EMBANKMENTSAND THEIR BASEMENT IN RESULTS OF EXPERIMENTAL WORKS Summary Analysis of flood disasters argue over half of such cases resulted from specific flood embankment conditions and their basement. Most common are 10 kinds of reasons of flood embankment damages and for their study could be used geophysical methods. These reasons are: embankment location on oxbow area, caverns and slacknesses within embankment, preferential ways of infiltration, various basement compressibility and discontinuouities of impermeable mud layer. In first half of eighty were carried some experimental studies on several parts of flood embankments from Wisła and Noteć rivers. Field geophysical works were done on various embankment kinds using four methods: resistivity, seismic, gravimetric and geothermic. On Wisła river these studies have concentrated on its upper and middle parts, in last one - Płock region on which in winter 1982 the immense flood disaster took place as result of embankment disruption. This article presents methodology of field works, examples of results and discussion about possibilities and use of applied methods. These investigations proved geophysical methods allow to find some anomalous phenomena and elements of embankment structure and its basement, being important menace for their stability and flood control value. Some suggestions of methodological-organizational modifications, enhancing efficiency of geophysical works, were also proposed.