1、中文4490字出处：Environmental geology, 2005, 49(2): 267-273PDF外文：http:/ resistivity measurements for dam safety evaluation at Enemossen tailings dam in Southern Sweden Internal erosion is a major Reason for embankment dam failures. Resistivity measurements is an essentially non-destructive technique, whic
2、h may have the possibility of detecting internal erosion processes and anomalous seepage at an early stage before the safety of. The dam is at stake. This paper presents results from part of a dam Safety investigation conducted at the Enemossen tailings dam in southern Sweden. Longitudinal resistivi
3、ty sections, 2D measurements along the dam crest, provided an overview of the whole dam and served to detect Anomalous zones. In selected areas, additional cross-sectional 2D surveys gave detailed information about the geoelectrical situations in the embankments. This information is valuable for sim
4、ilar investigations as information about resistivity in embankment construction material is scarce. Known problem areas were associated with low resistivities, even though the resistivity measurements alone did not provide enough information to confidently come to a decision about the status of the
5、dams. Embankment dams are made of earth or rock. Internal erosion is one of the major causes of embankment dam failures. Resistivity measurements may have the possibility of detecting internal erosion processes and Anomalous seepage at an early stage before the safety of the dam is at stake. The tec
6、hnique is essentially non-destructive, which is particularly important when working with embankment dams where drilling and other penetrating investigations are preferably avoided. This paper presents results from part of a dam safety investigation conducted at the Enemossen tailings dam in southern
7、 Sweden. Tailings dams are a type of Embankment dam that impounds mining waste. The mining waste, which consists of ?ne-grained waste materials left after mechanical or chemical separation of minerals from crushed ore, is typically pumped into a storage reservoir and the tailings dams are built to h
8、old these volumes in place. The aim of this study was to examine the extent of the damage around the latest reported sinkhole and to examine the integrity of the entire dams in order to detect other deficiencies. The investigation comprised temperature, resistivity, induced polarisation (IP) and sel
9、f potential (SP) measurements together with standard visual inspections and piezo meter readings. Part of the results from the resistivity measurements will be presented here. Measuring temperature over time is a powerful and sensitive way to detect leakage pathways and to estimate fillow rates. The
10、 methodies, however, limited to aspecific area, and the same goes for most conventional methods. Other methods with the possibility to scan larger areas are therefore requested, and most geophysical methods are of this kind. Among the methods tested, resistivity measurements were considered the most
11、 successful. A general overview of all measurements, as well as a more detailed description of the dams, is given by Salmon and Johansson (2003). In recent years much effort has been put into dam safety work in Sweden. During the same time a number of incidents involving tailings dam have occurred,
12、which have increased consciousness among the public and the authorities. As a consequence, strong focus has also been put on dam safety for tailings dam. Eight large tailings dams were in operation in Sweden in 2003, and an additional one commenced in 2004.Three of them have been subjected to uncont
13、rolled erosion through the dam body or the foundation over the last 10-yearperiod, and one of these incidents developed to a complete failure (Benckert2003). When the electrical properties of the tailings distinguish from the surrounding materials, resistivity measurements can be used to asses
14、s leakage and propagation for environmental purposes. This type of investigations has been conducted many times as regard to mine drainage (e.g. Abraheemetal. 1990； Buselli and Lu 2001； Yuval andoldenburg 1996).The technique is similar to the one used to detect leakage from land fills. Using resistivity for safety investigations of tailings dams is, however, less common, but the technique is similar to leakage detection
