Stages and staging of the study of the seabed for earthmoving systems

Abstract

The development and development of minerals and building materials in water areas, the laying of underwater communications, planning and dredging underwater are preceded by detailed surveys of soil massifs. They establish the lithology and genesis of deposits, bottom surface bathymetry, physicomechanical, acoustic and other properties of underwater soils. These studies are mainly subordinated to the tasks of geology. At the same time, for the development of the deep-water part of the World Ocean, it is planned to use soil development and transport equipment. The kinematic parameters of the equipment used for engineering and geological research do not correspond to the kinematics of existing or planned underwater systems. Despite some progress in the development of engineering-geological methods for studying the ocean, there are currently no reliable data on the mechanical properties of bottom sediments in natural occurrence. Practically the only way to identify the strength properties of deep-water soils is the sampling method (tubes, grabs, dredges). Soil characteristics are determined from samples brought to the surface in a shore or ship laboratory.
 One of the specific features of the tests being carried out is the consideration of hydrostatic pressure, the effect of which on three-phase soils is especially large. Therefore, it should be expected that the measurement errors of the characteristics of bottom sediments in atmospheric conditions due to the violation of their structural relationships during ascent from great depths can differ by an order of magnitude or more from the true values ​​of the parameters of the soil environment. Thus, in order to determine the operating conditions and set external loads on underwater digging machines, it is necessary to measure the strength, deformation and other characteristics of bottom soils in natural conditions under hydrostatic pressure. This paper considers the methods and technical means used for deep-sea exploration of the seabed. Particular attention is paid to engineering-geological methods, which make it possible at the stage of detailed exploration to obtain not only predictive estimates of the mineral resources of the World Ocean but also to determine the physical and mechanical properties of bottom sediments, on which deep-sea digging machines will have to work.