METHOD OF CALCULATION THE STABILITY OF AN EXCAVATOR EQUIPPED WITH A CONE ROLLER

Author(s):  
K. Z. Tilloev ◽  
S. V. Kondakov

The construction and method of calculating the stability of a crawler excavator equipped with a new working body (cone roller) are considered. The calculation is made on two working positions (longitudinal and transverse) of the excavator, provided that the excavator must apply the maximum force on the working body at an angle of 90°. The force applied by the excavator boom to the cone roller during the introduction depends on the physical and mechanical properties of the compacted soil. The calculation method differs in that during the compaction of the roadbed, the cone sinks into the ground, and the excavator tends to roll in the direction of the rear track support roller, in contrast to the traditional danger of tipping over the front support roller when working with a bucket.

2019 ◽  
Vol 945 ◽  
pp. 433-437
Author(s):  
M.D. Sokolova ◽  
A.F. Fedorova ◽  
M.L. Davydova

The present paper outlines the results of full-scale tests of climatic stability and the study of resistance to the action of hydrocarbon media of rubbers based on BNKS-18-18 (butadiene-nitrile rubber) and Hydrin T6000 epichlorohydrin rubber containing one of 6PPDstabilizerwith an aromatic amine moiety widely used in synthetic rubbers. Samples are exposed in an open ground under natural conditions of exposure to climatic external factors of Yakutsk in the Republic of Sakha (Yakutia), as well as in the oil environment of Talakanskoye field and I-50A hydraulic fluid in an unheated room. Such indexes of the samples as conditional tensile strength, elongation at rupture, hardness and degree of swelling are measured to determine the resistance of rubbers to aging after the first, third, and sixth months of exposing. The results of the study reveal the contribution of 6PPD stabilizer in maintaining the stability of the physical and mechanical properties of BNKS-18: rubber containing 6PPD has less property changes both in the open air and in hydrocarbon media compared to rubber without a stabilizer. It should be noted that the oil environment is the most aggressive environment, the swelling of rubbers in oil leads to a significant reduction in strength due to a decrease in intermolecular interaction.6PPD stabilizer occurred less effective for the rubber based on Hydrin T6000: changes in properties of the samples containing the stabilizer are larger than those of the samples without the stabilizer. However, unlike BNKS-18-18-based rubber, the swelling of rubber based on Hydrin T6000 led to the greatest stability of the physical and mechanical properties in the oil environment compared to the open air and hydraulic fluids.


2011 ◽  
Vol 331 ◽  
pp. 270-274 ◽  
Author(s):  
Yan Yan Chu ◽  
Qing Wang ◽  
Shi Zhong Cui

Abstract:Pure TiO2 water sol, pure ZnO water sol and three compound TiO2/ZnO water sols are prepared under low temperature. Then the padding and baking process is used to put the functional sol liquid on the fabric. SEM is use to analyzed the change of surface feature and the result show that all of the water sol except pure ZnO water sol liquid formed a thin film on the fiber The stability of pure ZnO water sol is the best one and the pure TiO2 water sol is the worst one at temperature of 15°C. The compound water sols stabilities are between these two water sols and with the more amount of ZnO, the stability last longer. Both mole of TiO2 and ZnO with the rate of 5 to 5 and 7 to 3 display the best antistatic behavior, but the washing fastnesses are not good. After treatment, the moisture regain displays most dramatically changes; the next one is whiteness of fabric, but the other physical and mechanical properties have a little change.


2018 ◽  
Vol 2018 ◽  
pp. 1-14 ◽  
Author(s):  
Yanbo Feng ◽  
Chao Yang

Red mud is the tailings generated from the production process of aluminum industry and is mainly stacked in open-air at present, so how to ensure the stability of red mud stockpile is very important. Regarding mud stockpile of Guizhou Aluminum Factory as the research object, this paper studies the physical and mechanical properties of Bayer red mud from wetting process, Bayer red mud from drying process, and sintering red mud through laboratory test and finally analyzes its stability under extreme rainfall condition in this region by the Geo-Studio software. The research results show that the red muds in different processes have big difference in physical and mechanical properties. The strength of sintering red mud is about 4.2 times of that of Bayer red mud from wetting process on average, and the strength of Bayer red mud from drying process is about 1.5 times of that of Bayer red mud from wetting process on average. So, the sintering red mud can be used as the subdam of red mud stockpile, to reduce the risk of collapse and dam break. The stability coefficients of the mixed stocking method under three rainfall conditions are 2.611, 2.597, and 2.631, respectively, all of which are above 1.0. It reveals that the dilatation scheme of using the sintering red mud with good engineering properties to stockpile the Bayer red mud is feasible. It can not only guarantee the safety and stability of red mud stockpiles, but also reduce the risk of red mud dam break and the capital investment of red mud yard.


Author(s):  
A. B. Petrovsky ◽  
V. Ya. Prushak ◽  
E. A. Lutovich

The geological structure and the physical-mechanical properties of rocks composing and overlapping the Third potash formation in the areas of the mine field mine No. 4 JSC Belaruskali, which are scheduled to practice, are studied. The geological sections of the Third potash layer and its roof were built, the thickness of sylvinite and halite layers was measured, the roof falling of the rocks of the layer with a height of up to 20 m was assessed, and the type of immediate roof was determined by the composition and structure of its constituent rocks. It was established that the strength under uniaxial compression of both sylvinite and halite layers for the areas under consideration differs slightly. Therefore, to solve engineering problems of ensuring the stability of mine workings and to calculate fastening parameters, strength values averaged over the groups of layers can be used that correlate well with the percentage of weak and clay interlayers. The same applies to Poisson’s ratio, the values of which for various layers of formation are slightly different and can be taken by their averaging. It is shown that the main factor that negatively affects the strength of rocks occurring in the roof of the Third potash seam is the presence of weak and clay interlayers, which increases with depth. The introduction of the obtained results allows us to improve the calculation accuracy of securing mining parameters, to reduce the costs of their maintenance, and to improve the safety of mining operations in developing the Third potash formation in complex geological and mining conditions.


Author(s):  
Xudong Hu ◽  
Jiazhen Gao ◽  
Mingtao Zhou ◽  
Songtao Peng ◽  
Wennian Xu ◽  
...  

The physical and mechanical properties of the ecological slope protection substrate will be affected by long-term variation of the meteorological condition, resulting in the stability of the substrate being reduced. So an artificial substrate of vegetation cement-soil was selected as the research object to prepare specimens with the different initial moisture content of 13%, 19%, 25%, 31%, 37%, and 43%. And a series of tests are conducted to investigate the evolution of the physical and mechanical properties under drying-wetting cycling conditions. Typical results of the vegetation cement-soil evolution can be divided into three stages: cement hydration stage, shrinkage stage, and stabilization stage. In terms of different initial moisture content, the shrinkage cracks number, cracks length, crack width, and cracks surface area are increased first and then stabilize with the increase of the number of drying-wetting cycles. In contrast, the cohesion and internal friction angle of the vegetation cement-soil is reduced with the increase of the number of cycles. Comprehensive analysis shows that the initial moisture content of vegetation cement soil ranges from 25% to 31% is the optimal choice to ensure substrate stability in production practice.


Author(s):  
V. D. Cherepanov ◽  
S. G. D’yachkova ◽  
I. I. Kuzora ◽  
D. A. Dubrovskii ◽  
V. I. Lukina

Abstract: Using the example of oil road bitumen grades BND 100/130, BND 130/200 and BND 70/100, this article studies the transformation of oil dispersed systems under various logistic schemes of operation. This research focuses on the influence of the conditions for storing road bitumens of different grades on their physical and mechanical properties and group hydrocarbon composition during transportation from the manufacturer to the consumer. The results show that a change in the physical and mechanical properties of road bitumens during high-temperature storage is related to the changes in the group hydrocarbon composition due to the hydrocarbons autooxidation and destabilization of the colloidal structure of dispersal systems. The conditions for storing bitumen with a minimum change in its quality indicators have been determined. It has been established that storage of bitumen under atmospheric conditions allows preserving its original properties without significant changes. There is evidence that nitrogen purging significantly reduces the effect of homolytic processes leading to the transformation of oil dispersed systems during further transportation from the manufacturer to the consumer. Experimental data confirm that of all basic physical and mechanical properties of bitumen, “the depth of penetration of needle” is the most sensitive index, while the “softening temperature” index, frequently used for quality control of bitumen, is inertial. Determining the change in penetration, depending on the duration of storing bitumen, has required formulating a special equation. It has been established that when storing road bitumen at a temperature of 180 ºС, for each hour the index of the penetration depth of the needle at 25 º decreases by 0.8 units. Organizational and technical measures have been determined to ensure the stability of the road bitumen quality during manufacture, storage and transportation to consumers.


Author(s):  
M. I. S. Fazlina ◽  
Putera Agung Maha Agung ◽  
A. T. S. Azhar ◽  
Muhammad Nizam Zakaria ◽  
Mustaffa A. Ahmad ◽  
...  

The most fundamental of unsaturated soil is matric suction parameter. Matric suction in unsaturated soils plays an important role in controlling physical and mechanical properties. This parameter can influence some other important parameters of soil, such as effective stress, shear strength, swelling pressure, etc. Investigation of matric suction was performed on Ayer Hitam soil, at Batu Pahat District, Johor, Malaysia. Field monitoring works were conducted with and without dolomite treatment at the slopes of Ayer Hitam acidic soil. Field testing used some devices to find out the behavior of matric suction during the rainy session. The result shows that the soil matric suction with dolomite treatment is larger than without treatment and matric suction has a significant difference around 20 – 50 kPa. Enhancement of acidity from the dolomite treatment was not only decreasing pores size caused by the alternating of the microstructure of soil but also leading to increasing the matric suction. The treatment of dolomite material is able to control matric suction and increase the stability of slope acidic Ayer Hitam soil.


2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Lujing Zheng ◽  
Yujun Zuo ◽  
Yafei Hu ◽  
Wei Wu

In this study, the analysis and control of stability of surrounding rock in deep fractured soft rock roadway located in the underground mine of Jinfeng gold mine in Guizhou Province, China, has been investigated. The surrounding rock of roadway has been analyzed to characterize its deformation and failure mechanism through field survey, testing of rock physical and mechanical properties, in situ stress measure, analysis of mineral components of rock, and investigation of rock fragmentation degree. Based on the numerical simulation technology, the influence of different factors on the stability of roadway is studied. The physical and mechanical properties of surrounding rock and the bearing capacity of surrounding rock layer are to be improved to maintain the stability of broken soft rock roadway as high ground stress, rock fragmentation, and poor lithology leading to tunnel instability. Hence, a high-strength “cable bolt + fiber-reinforced shotcrete + steel mesh + split sets + resin bolt + cement grouting” combined support system has been proposed to improve the effective bearing structure significantly with high integrity and bearing capacity.


2021 ◽  
Vol 280 ◽  
pp. 08014
Author(s):  
Yevheniy Babets ◽  
Oleh Anisimov ◽  
Oleksandr Shustov ◽  
Vitalina Komirna ◽  
Iryna Melnikova

The safety factors for different variants of operation development were obtained, on the basis of which the technical and economic indicators were established and the most expedient way of restoration of dump operations in conditions of the formed landslide was chosen. The solutions were proposed for the external dump No 2 of the Central Ore Mining and Processing Enterprise (COMPE), that allow to continue its future operation. When working in the conditions of the formed landslide, three variants of the further dump operation are modeled: the first one - with landslide removal and unloading of the upper dump horizons, the second one - without landslide removal and involvement of disturbed lands in land allotment, the third one - with the landslide loading. Based on the built sections of the dump and defined physical and mechanical properties, the stability factors were obtained for different options of the operation development, which made it possible to determine the appropriate option to eliminate the effects of the dump slide deformations. As a result of the calculations, the cost flows for each of the proposed options of the formation of the end contour of the dump No 2 are determined.


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