Uneven pressure on the strip foundations of building extensions due to the influence of their free ends often leads to the setting extensions aside from the main building, and uneven pressure on the ground of bridge abutments from adjoining embankments can cause the abutments slope in the direction of the embankments. This took place in Dneprodzerzhinsk (Ukraine) on railway and highway bridges, and abutments slope nearly caused the breaking-down of the bridge superstructures. The plane problem solution of the theory of elasticity for a loaded strip of an infinite length used in calculating is inefficient. The presented solution of the spatial problem for a semi-infinite length strip load specifies the ground stress condition at the free ends of the strip foundation, and also in foundation grounds of the bridge abutments from the pressure of adjoining embankments. The components of even load stress and triangular load stress σ_z are obtained by integration of stress values for the elementary concentrated force over the area of the strip. The other components of triangular load stresses, according to the known solution defining stresses, were under the rectangular foundation of the same load. The solution: central point of coordinates moves along the y-axis from the center of the foundation to its end; the target stress components are of stress components under a rectangular foundation by defining the limit of these stresses, when l → ∞. The obtained solutions satisfy the conditions on infinity; the normal stresses σ_z , σ_x and the shear stresses τ_zx change to the known solutions for the plane strain when - ∞ ← y → ∞ . The stresses τ_xy and τ_yz are damped approximately on the distance of y = 2,5b from the strip end, and the stress σ_y becomes permanent and is not taken into account when calculating. Subtracting from the solution corresponding to the strip of a semi-infinite length with the central point of coordinates of x = 0, y = 0 , the same solution with the central point of coordinates of x = 0, y = l for even stress and respectively x = -b / 2, y = 0 and x = -b / 2, y = l for the triangular load we get an easier solution compared to the known one which determine the stress components at the rectangular foundation ground. So that, knowing the solution for any kind of strip load it is possible to find the solutions for rectangular foundation and vice versa. The obtained formulas allow solving plasto-elastic tasks. Here, b and l are the width and the length of the strip.

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Mud eruption occured in East Java, 3 days after the Jogyakarta Earthquake in May 26, 2006 where at the site, deep drilling was being conducted. The mechanism of the causes of the eruptions are still in debate, whether trigerred by the drilling or pressurised fluid reactivated by the quake. However the objectives of this paper is to discuss mainly on the geotechnical aspects of the mud eruption which spread in larger area until today. In the early days of eruption, as much as 150,000 cubic meters discharge per day was reported, although presently only less than 5000 cubic meters of the discharge is estimated. Due to unknown characteristics of the mud, dykes were constructed to contain the mud and the areas being much larger to reach 450 hectares in 2006 and becoming larger in 2007. The location of the disaster is just in the middle of the town of Porong in the district of Sidoardjo, where the Surabaya International airport is located and has block the major arterial roads from north to south of east Java. The soil condition of the site is deep soft clays which causes instability of the dykes. Some dyke failures occured which endangered the residential areas due to the flow of the mud. This paper desscribe the characterics of the soil conditions from a number of drillings and CPTu conducted by the author for design of the replacement of the arterial road, west of the site. The paper discuss the geotechnical problems of land subsidence in large areas and differential settlement that causes damages of the infrastructures, including the roads, gas pipes, railways, the bridges and the buildings. The mud has been discharged through the Porong river, and the sedimentation is being part of the problems.

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Production of precast concrete requires a large amount of thermal energy, especially the technological process to accelerate concrete hardening. Application of helioforms with various translucent and solar perceptive coatings can be considered as one of the directions of solar energy application for thermal treatment of precast concrete. Heliothermаl treatment of precast concrete products in helioforms, using such coatings ,has been developed in the late 70th of the last century on the basis of research, conducted by scientists of scientific-research institutes of the Commonwealth of Independent States. Various ways of heliothermаl treatment of concrete using translucent and solar perceptive coatings were proposed and tested. One of the simplest and most effective ways to accelerate hardening of concrete using solar energy, which found quite wide application in practice, is thermal treatment of heavy concrete products in helioforms with translucent and heat insulating coatings (THIC). This method of heliothermаl treatment in regions with hot climate allowed to abandon for 5-6 months a year (for a number of slab by products) the heat-humidity treatment with the use of other heat carriers; to reduce demand for water used to generate saturated water steam; to create seasonal testing grounds for thermal treatment of concrete with solar energy application; to create a clean quality environment for the production; and with all this, to ensure the diurnal cycle of manufacture of products. However, for heliothermаl treatment with the use of THIC coatings helio top covers are needed, that require constant care of translucent liners; impossibility to use the existing helio top covers for the manufacture of products of another type/size; difficulty in manufacture of products of complex shapes according to this technology, etc. Development of advanced technologies of solar energy application to accelerate the hardening of concrete in the manufacture of concrete products will ensure high quality of precast concrete products due to creation of optimal structure of concrete as a result of the most favorable temperature - humidity conditions of concrete hardening, rational formation of temperature fields in products and heat -and -mass transfer. New approaches to the technology of heliothermal treatment of precast concrete structures in dry hot climate of the Republic of Kazakhstan save 50-100% of traditional fuel at their thermal treatment of precast concrete; ecologically clean quality environment, free of smoke emissions from boiler installations; guaranteed high quality of products and constructions at the diurnal cycle of turnover of the forms, reduction of the cost and energy intensity of construction.

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Russian method for soil compaction with the help of the vibrating driver of longitudinal vibration with a spatial compactor is used throughout the world for vibratory compaction of sandy foundation soils which can be water-saturated or slightly damp or combined together. The paper provides the results of the theoretical justification on the basis of a design model and field tests of this method for deep vibratory compaction of foundations, which show its disadvantages. These disadvantages manifest themselves the most clearly during the compaction of especially thick sandy foundations (9 m and more). This paper shows that the disadvantages of the well-known vibrating driver can be eliminated or reduced dramatically when using a vibratory compactor with radial elements placed at a certain height at the lower part of its rod. This helps to improve the performance of the vibrating driver when it is used together with a reliable and economical vibratory device.

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Assessment of frost susceptibility of clay soils is challenge for civil and road engineering. Inaccurate classification can result to damage roads, pipelines and building foundations. The most reliable way to get valid value of frost heave deformations is to measure it in in-situ. The article deals with results of in-situ measurements of frost penetration and frost heave via automatic monitoring system. The main idea of the monitoring system is to measure temperature and layered deformations of frost heave at the same time. Due to embedded magnetic marks in soils and magnetic sensors in probes frost heave deformations are defined as a function of changing magnetic field. The system is gathering information to local data storage and every day the data are transmitting to internet by using UMTS/EDGE/GPRS/ GSM mobile network. Results of laboratory testing and in-situ monitoring are presented.

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