This paper presents the results of in-situ stress measurement and analysis in Xishimen Iron Mine. A rotating stress field in which the major principal stress is in horizontal direction was measured in the Mine area. The varying trend of direction of the major principal stress from north to south is NE-NS-NW. The relationship between the magnitude of the horizontal principal stress and the earth"s depth, and the ratio of the average horizontal stress to the vertical stress were obtained. The ratio also varies with the earth"s depth. Suggestions are given about how to design and maintaining the stability of the openings under the measured stress field condition.
Cet article present les resultats mesurables et analysables des contraintes aux fonds du mine de fer Xishmen. La plage de la contrainte rorative se compose principalement la contrainte compressive horizontale dans la zone minière. La direction de transformation de contrainte principale maximale est la variation de sud a nord, soit NE-NS-NW. Avec la variztion de profondeur nous obtenous en mème temps la contrainte horizontale et la loi de variation de propotion k qui est relation de la contrainte horizontale moyenne avec celle verticale. De la part de la plage de contrainte l"auteur a propose des propositions pour relever la stabilite de la dalerir de mine et pour la scientificite des projects de l"exploitation.
In diese Bericht wird das Messungs-und Analyse ergebnis der in-situ Beanspruchung in Xishmen Eisenbergbau: gegeben. In Bergbauzone wird das Rotationsbeansprungsfeld, in dem die horizontale Druckbeanspruchung die groesste prinzipielle Beanspruchung ist, gemessen, die Veraenderungstendenz der groesster prinzipieller Beanspruchung von Nord zu Sued ist NE→NS→NW. Die, Abhaengigkeit der horizontaler Beansprung von der Aenderung der Erdetiefe und Die Abhaengigkeit des Verhaelthesses "K" zwischen der durchschnittlicher horizontaler Beansprung und der vertikaler beansprung von der Aenderung der Erdetiefe werden festgestellt. Einige Vorschlaege ueber die Erhoehung der Stabilitaet der Bergoeffhung und Verbesserung der Bergbaukonstruktionwerden unter der Beruecksichtigung des Beansprungsfeldes gestellt.
Xishimen Iron Mine is located in the middle eastern side of the Taihang Mountains. It is a joint zone of Taihang upheaval zone and northern China subsidence zone. Reapeted tectonic movements made the stress field in the mine area very complicated. A knowledge of the actual stress state in this area is desired for design and analysis of the stability of the mine.
The device used to measure stress field in Xishimen Mine in 1987 and 1989 was a hollow inclusion stress cell made by Beijing Institute of Geomechanics, whose configuration is shown in Figures 1 and 2. The cell is composed of a epoxy resin shell, a hollow plunger, a lead wire cable, two sets of seals and four fixing pins. Three rosettes of four strain gauges are embedded in the epoxy shell along a circumference with a interval of 120°. An additional strain gauge is cemented on the end of the cell for temperature compensation.
(Figure in full paper)
Immediately before installation of the cell, cement is filled in the chamber of the shell. When the cell is inserted into the installation hole.