Abstract: A compacting machine having a vibrating drum for compaction of ground material includes a controller. The drum is moved over a segment of the ground while a shear modulus and a plastic parameter of the segment of the ground are measured. From the measurements, in particular the value of the shear modulus, values for the frequency and/or the amplitude of the vibration and/or the rolling velocity of the drum are determined. These values are used for adjusting the compacting machine. In the measurement of the shear modulus, two accelerometers are used for determining, during the passing of the segment of the ground, the acceleration of the drum in at least an essentially vertical direction. The amplitude and the phase position of the eccentric system in relation to the acceleration are determined by using, among other things, a pulse sensor. Therefrom, and from fixed data concerning the compacting machine, the shear modulus of the ground is determined by integration of state equations.

Abstract: A process for the treatment of complex metal sulphide materials and for the recovery of metal values from such materials. The process involves first subjecting the material to a leaching process under conditions such that sulphide-sulphur is oxidized to sulphate and such that oxidized iron and impurities such as As will pass into solution, whereafter the leaching residue is melted for conventional pyrometallurgical recovery of the metal values.Different embodiments of the process provide for the recovery of precious metal values from refractory materials containing such values and for the recovery of metal from complex copper concentrate and complex nickel concentrate.

Abstract: Method and apparatus for compacting a layer of material using a compacting machine having at least one drum which is rolled over the layer; the material layer is acted on by gravitational force of the roller and an oscillating force. The latter is the result of applying a rapidly substantially alternating torque to the drum about its axis. The direction of action of the torque is reversed with a high frequency in relation to the frequency with which the direction of travel of the compacting unit is reversed. The invention also embraces means for executing the method wherein the torque on the drum is provided by at least two synchronously operating, rotating eccentric means spaced from the shaft of the drum, and which are adapted such that the forces caused by their synchronous movement can substantially neutralize each other radially to the drum and co-act to form a pure torque on the drum about its shaft.

Abstract: The invention refers to a procedure and a device for measuring the degree of compaction attained when compacting a foundation by means of a vibrating compaction tool. The movement of that part of the compaction tool which rests on the foundation is sensed and analyzed. The time interval elapsing between successive passages of the movement signal through the zero point or other reference level is measured. Alternatively, the ratio between the absolute values of the extreme positive and extreme negative values of the motion in relation to the said level is also measured. By means of the relative magnitudes of these time intervals and amplitude relationships respectively a quantity is formed which comprises a measure of the degree of compaction of the foundation.