Mechanical effects of grouting could have not been applied to the design of the foundation because of the lack of the basic data. If the degree of mechanical improvement of rock masses can be obtained quantitatively, the effective design could be carried out. In this study, a large number of borehole expansion tests (a total of 1600 tests) before and after grouting were carried out at 17 sites in order to examine the grouting effects on deformability of rock masses.
Les effets mecaniques de injection de ciment n' ont jamais encore ete appicable audessein de la fondation. parce que on a manque de donnees fondamentaux. Si Le degre de amelioration de masse de rocher peut etre obtenu quantitativement, un dessein efficace peut etre fait. Dans cette etude, beaucoup de tests de trous de sondages (1,600, au total) ont ete effectue a 17 lieux avant et apres la injection de ciment, pour verifier les effets de injection de ciment sur la deformabilite des masses de rocher.
Einwirkungen von Injektionen aufder Verformbarkeit applizieres nicht Design von Basis konnen infolge das Defizit von Data die Grundeinheit. Wenn der Grad von Einwirkungen von Injektionen von Felsemassen hatte begreifen konnen quantitativ, wirksam Design wurde machen kann. In das Studium, ein Menge der Btunnen erweitern Test (1600 alles zusammengerechnet) vorn und hinten Injektionen wurde macht bei 17 Stellen um Einwirkungenvon lnjekrionen auf der Verformbarkeit zu untersuchen.
Recently, with the lack of excellent foundations, more or less unstable rock masses would be selected as dam foundations. Therefore, the improvement of rock masses (foundation treatment) is indispensable in order to secure the stability of foundations. Consolidation grouting is mainly carried out at the foundation of concrete dam such as arch dam and gravitation dam. The aim of the consolidation grouting is to improve the deformability and intensity of rock masses by filling up crack with grout milk. It is also effective for controlling seepage flow at the part where hydraulic gradient is the highest. The effect of consolidation grouting is usually confirmed by referring the results of permeability tests. In the case that the discontinuities in rock masses are filled with grout milk, the permeability would be low. Such a confirmation method is not enough to grasp the mechanical properties of rock masses quantitatively. Therefore, the mechanical effects of grouting could have not been applied to the design of the foundation. If the degree of mechanical improvement of rock masses can be obtained quantitatively, the effective design could be carried out. In this study, the authors have made a large number of borehole expansion tests in order to examine the grouting effects on deformability of rock masses.
In this study, a total of 1600 borehole expansion tests were carried out before and after grouting. 17 sites (8 different rock types) were selected as the testing yards as shown in Table 1. Primary to quaternary holes are laid out in a testing yards. The distance between primary holes is 5 meters.
