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Base leveling is an important process in the construction of gravity structures, and its construction quality affects the quality of the structures. The base ramming and leveling of gravity structures in hydraulic engineering generally uses hammer ramming method and blasting ramming method, which have a low construction efficiency and a significant environmental impact. To address the above problems, through engineering verification, a vibratory ramming and leveling ship for underwater rubble base is developed. The main structure, working principle, technical performance and design influence factors of the vibratory ramming and leveling ship are introduced. The vibratory ramming and leveling equipment operates reliably during use, which greatly improves the construction efficiency and reduces the construction costs. [ABSTRACT FROM AUTHOR]

There have been carried out numerical studies and analysis of the stress-strain state of soil foundation for various ramming base shapes: flat, convex and concave under static load. Проведены численные исследования и анализ напряженно-деформированного состояния грунтового основания для различных форм подошв трамбовки: плоской, выпуклой и вогнутой при статическом действии нагрузки.

Ensuring the reliability and durability of buildings and structures built on subsident soils is one of the important tasks. Subsidence of the soil can lead to a violation of the strength of buildings and structures and the impossibility of their further operation. It is necessary to improve the existing methods of preparing the foundation. This article discusses the experience of using the method of soaking the thickness of subsident soils in combination with the device of a rammed soil cushion. Works on compaction of subsident soils by soaking and tamping are carried out sequentially on three maps. Soaking is carried out through trenches with a depth of 2...3 m, a width of 2.0 m. All the soil from the trenches is stored inside the maps to create a load, as a result of which an additional pressure on the soil is created, equal to 10...30 kPa. At the next stage, local pits are rammed under the buildings according to a given grid, which are filled with local soil with layer-by-layer compaction. Compacted areas around the pits overlap, and as a result, a rammed soil cushion is created, which makes up a single compacted array. Thus, the elimination of subsidence properties of the soil is achieved.

There have been carried out numerical studies and analysis of the stress-strain state of soil foundation for various ramming base shapes: flat, convex and concave under static load. Проведены численные исследования и анализ напряженно-деформированного состояния грунтового основания для различных форм подошв трамбовки: плоской, выпуклой и вогнутой при статическом действии нагрузки.

The effect of cold-ramming hearth mix density on the annealed mix dynamic elastic modulus is investigated. It is shown that analysis of the elasticity modulus curves makes it possible to determine the area of optimum hearth mix compaction within which it has a mechanical property level comparable to hearth blocks.

Recently, researchers in Korea and abroad actively have conducted research activities using the ARAON, a Korean icebreaking research vessel. The ARAON regularly conduct research activities in the Arctic and Antarctic waters every year. The icebreaking mode, which can be either continuous breaking or ramming, is determined by the conditions of the ice and the ice-covered waters. When the icebreaker encounters thick sea ice or an ice ridge, ramming is used. At that time, the speed of the ship generally is slower than that of continuous icebreaking. In this study, the ice load signal at the time of repetitive ramming during ARAON’s 2012 Antarctic research voyage was analyzed. The time history of the ice load signal and the change in the speed of the ship used in ramming were compared with these values during continuous icebreaking.

В статье показана проблема суицидальных атак как средства политической борьбы. Раскрыта актуальность своевременного выявления лиц, имеющих террористические замыслы суицидальной направленности. Дано сравнение японских камикадзе и советских военнослужащих, совершавших технические тараны в период Второй мировой войны. Показана правовая неурегулированность таких таранов в советском законодательстве наряду с широким пропагандистским освещением в печати., The article explores the problem of suicidal attacks as a means of political struggle. It points out the relevance of timely detection of individuals with suicidal terrorist intentions. The author compares Japanese kamikazes and Soviet military personnel who performed ramming during World War II. The article also shows the lack of legal regulation of such ramming attacks in the Soviet legislation, along with extensive propaganda coverage in the press.

Bighorn sheep rams participate in high impact head-butting without overt signs of brain injury, thus providing a naturally occurring animal model for studying brain injury mitigation. Previously published finite element modeling showed that both the horn and bone materials play important roles in reducing brain cavity accelerations during ramming. However, in that study the elastic modulus of bone was assumed to be similar to that of human bone since the modulus of ram bone was unknown. Therefore, the goal of this study was to quantify the mechanical properties, mineral content, porosity, and microstructural organization of horncore cortical bone from juvenile and adult rams. Mineral content and elastic modulus increased with horn size, and porosity decreased. However, modulus of toughness did not change with horn size. This latter finding raises the possibility that the horncore cortical bone has not adapted exceptional toughness despite an extreme loading environment and may function primarily as an interface material between the horn and the porous bone within the horncore. Thus, geometric properties of the horn and horncore, including the porous bone architecture, may be more important for energy absorption during ramming than the horncore cortical bone. Results from this study can be used to improve accuracy of finite element models of bighorn sheep ramming to investigate these possibilities moving forward.

The purpose of research - a comprehensive assessment of specialized machines for laying silage in land storage on quality indicators, the establishment of design features and their impact on the quality of the technological process. Research methods: visual inspection and analysis of design features of machines; measurement of indicators of quality of performance of technological process with use of means of measuring equipment according to GSTU 46.007-2000. «Agricultural machinery. Machines and equipment for preparation of forages. Test methods «; timing observations during operational and technological evaluation.The results of research: measurement of the parameters of the technological process of silo pitchforks was performed on the distribution of corn silage in concrete trenches. The content of particles with a length of not more than 30 mm from the total mass of crushed corn milk-wax ripeness of the grain is 97%. The temperature of the ensiled mass during laying in the trench was at the level of 26.3 ° C. The research results show that the silage forks perform the technological process satisfactorily. The uniformity of the distribution of silage is 95.4%, the thickness of the layer of silage after the first pass of the unit - 15.5 cm, after the second pass - 10.0 cm. The productivity of the unit was 140 tons per hour of main time and 123 tons per hour of variable time. Hourly operating costs of the unit were obtained equal to 1586.31 UAH / hour. Direct operating costs per 1 ton of feed at variable productivity is UAH 12.90. The forks have a simple design, convenient for maintenance and technological maintenance. Measurements of the parameters of the technological process of the silage roller were performed in the unit with a JOHN DEERE 6135B tractor on compaction of corn silage in the phase of milk-wax ripeness of grain. The test conditions were typical for all zones of Ukraine. Productivity on compaction of silage from corn in a concrete trench made 51,0 t for an hour of the main time. According to the test results, the roller reliably performs the specified technological process (the coefficient of reliability of the technological process is equal to 1.0). Taking into account the time spent on operations to ensure the technological process (shifting maintenance, preparation and completion of work, commissioning, rest, idling), the coefficient of use of variable time is 0.88. Hourly operating costs of the unit are 1061.29 UAH / hour, direct operating costs are - 23.63 UAH / t. Conclusions: Silage forks ВС-3,5 provide high uniformity of leveling of silage with productivity of 140 tons for an hour of the main time. Silo roller KS-3000 «Profi» due to sealing ribs with a small area of сontact with the ensiled mass creates a high local pressure and allows to obtain a mass density greater than 700 kg/m3 with satisfactory performance of the process. The use of relatively inexpensive specialized machines allows you to rationally and efficiently use the energy available on the farm during the procurement of feed., Цель исследований: комплексная оценка специализированных машин для закладки силосной массы в наземные хранилища по показателям качества, установление конструкционных особенностей и их влияние на качество выполнения технологического процесса. Методы исследований: исследование осуществляли визуальным осмотром и анализом конструкционных особенностей машин; измерением показателей качества выполнения технологического процесса с использованием средств измерительной техники согласно ГСТУ 46.007-2000. «Техника сельскохозяйственная. Машины и оборудование для приготовления кормов. Методы испытаний»; хронометражными наблюдениями при эксплуатационно-технологической оценке. Результаты исследований: измерение параметров выполнения технологического процесса вил силосных проводили на распределении силосной массы кукурузы в бетонированных траншеях. Содержание частиц длиной не более 30 мм от общей массы измельченной кукурузы молочно-восковой спелости зерна составляет 97%. Температура силосной массы при закладке в траншею была на уровне 26,3 ° С. Результаты исследований свидетельствуют, что вилы силосные удовлетворительно выполняют технологический процесс. Равномерность распределения силосной массы составляет 95,4%, толщина слоя после первого прохода агрегата - 15,5 см, после второго прохода - 10,0 см. Производительность агрегата составила 140 тонн за час основного времени и 123 тонн за час сменного времени. Часовые эксплуатационные затраты работы агрегата составили 1586,31 грн./ч. Прямые эксплуатационные расходы в расчете на 1 тонну кормов по сменной производительности составляют 12,90 грн. Вилы имеют простую конструкцию, удобные в техническом и технологическом обслуживании. Измерение параметров выполнения технологического процесса катка силосного проводили в агрегате с трактором JOHN DEERE 6135B на трамбовке силосной массы из кукурузы в фазе молочно-восковой спелости зерна. Условия испытаний были характерными для всех зон Украины. Производительность трамбовки силосной массы из кукурузы в бетонированной траншее составляла 51,0 т в час основного времени. По результатам испытаний каток надежно выполняет заданный технологический процесс. С учетом затрат времени на операции для обеспечения технологического процесса коэффициент использования сменного времени составляет 0,88. Часовые эксплуатационные затраты работы агрегата составляют 1061,29 грн./ч., Прямые эксплуатационные расходы составляют - 23,63 грн./т. Выводы: Вилы силосные ВС-3,5 обеспечивают высокую равномерность разравнивания силосной массы с производительностью 140 тонн в час основного времени. Каток силосный КС-3000 «Профи» за счет уплотнительных ребер с малой площадью контакта с силосной массой создает высокое локальное давление и позволяет получить плотность массы больше 700 кг/м3 с удовлетворительной производительностью выполнения технологического процесса. Применение относительно недорогих специализированных машин позволяет рационально и эффективно использовать имеющиеся в хозяйстве энергосредства при заготовке кормов., Мета досліджень – оцінка спеціалізованих машин для закладання силосної маси в наземні сховища за показниками якості виконання технологічного процесу, есплуатаційно-технологічними та енергетичними показниками, встановлення конструкційних особливостей та їхній вплив на якість виконання технологічного процесу.Методи досліджень – візуальний огляд та аналізування конструкційних особливостей машин; вимірювання показників якості виконання технологічного процесу засобами вимірювальної техніки згідно з ГСТУ 46.007-2000. «Техніка сільськогосподарська. Машини та обладнання для приготування кормів. Методи випробувань».; хронометражні спостереження під час експлуатаційно-технологічного оцінювання.Результати досліджень – вимірювання параметрів виконання технологічного процесу вил силосних проводили на розподіленні силосної маси кукурудзи у бетонованих траншеях. Вміст частинок довжиною не більше 30 мм від загальної маси подрібненої кукурудзи молочно-воскової стиглості зерна становить 97 %. Температура силосованої маси під час закладання в траншею була на рівні 26,3 °С. Результати досліджень свідчать, що вила силосні задовільно виконують технологічний процес. Рівномірність розподілу силосованої маси становить 95,4 %, товщина шару силосованої маси після першого проходу агрегату - 15,5 см, після другого проходу – 10,0 см. Продуктивність агрегата становила 140 тонн за годину основного часу та 123 тонни за годину змінного часу. Годинні експлуатаційні затрати роботи агрегата склали 1586,31 грн./год. Прямі експлуатаційні витрати в розрахунку на 1 тонну кормів за змінної продуктивності становлять 12,90 грн. Вила мають просту конструкцію, зручні для технічного і технологічного обслуговування.Вимірювання параметрів виконання технологічного процесу котка силосного проводили в агрегаті з трактором JOHN DEERE 6135B на утрамбовуванні силосної маси з кукурудзи у фазі молочно-воскової стиглості зерна. Продуктивність утрамбовування силосної маси з кукурудзи в бетоновану траншею становила 51,0 т за годину основного часу.За результатами випробовувань коток надійно виконує заданий технологічний процес (коефіцієнт надійності технологічного процесу дорівнює 1.0). З урахуванням витрат часу на операції для забезпечення технологічного процесу коефіцієнт використання змінного часу становить 0,88, годинні експлуатаційні затрати роботи агрегата – 1061,29 грн./год., прямі експлуатаційні витрати − 23,63 грн./т.Висновки. Вила силосні ВС-3,5 забезпечують високу рівномірність розрівнювання силосної маси з продуктивністю 140 тонн за годину основного часу. Коток силосний КС-3000 «Профі» ущільнювальними ребрами з малою площею контакту з силосованою масою створює високий локальний тиск, чим отримується щільність маси понад 700 кг/м3 із задовільною продуктивністю виконання технологічного процесу. Завдяки відносно недорогим спеціалізованим машинам, наявні в господарстві енергозасоби використовуються раціонально й ефективно під час заготівлі кормів.

Investigations of the amount influence of corundum-zirconium-silicate material on the properties of ramming mullite-corundum mass of MMK-90 grade and samples from it are carried out. The optimum amount of the above material (40 % by weight) is established, the use of which in the composition of ramming mullite-corundum mass provides an increase in thermal shock resistance of the samples made of it (~ 2.0 times more) with sufficiently high strength properties and slag resistance, albeit lower, especially significant in strength, than samples without corundum-zirconium-silicate material. As a result of the carried out researches a new type of production is developed — ramming mullite-corundum mass of MMKTS grade with zirconium-containing component. The ramming mass of developed composition is characterized by the following indices of physical and chemical properties: Al2O3 — not less than 87.0 %; SiO2— within the range of 5.0—7.0 %; ZrO2 — in the range of 1.0—3.0 %; Fe2O3 — not more than 1.0 %; P2O5 — in the range of 2.5—3.5 %; grain composition, mm — 3—0; cold crushing strength of samples from the mass after firing at a temperature of 1580 оC is not less than 80.0 N/mm2. The developed ramming mass is recommended for making monolithic linings of thermal units with a service temperature of up to 1700 оC, in particular induction channel and crucible furnaces operating under conditions of sharp temperature fluctuations that occur during cyclic operation or unforeseen stops of the unit.

In this study, to develop a ramming mix, the D-optimal mixture design method was used, which makes it possible to achieve in the new type of ramming mix the optimal concentration of carbonaceous raw materials – silicon carbide, graphite, pitch. Using the expert-design software and a special preparation methodology, 16 samples of varying compositions were prepared, and their physical properties, such as dried and fired strength, were evaluated. In order to determine the optimal formulation, 12 models were studied. The model with the highest percentage of desired properties at 78.5% contained 11.7 wt.% silicon carbide, 2.6 wt.% graphite, and 5.7 wt.% pitch. Thus, this is the optimal composition of a ramming mix of the MgO–SiO2–SiC–C system for a blast furnace pig iron runner.

In refractory linings, the behaviour of ramming and mortar joints is essential for the performance of the whole structure. The compressive stiffness of commercially available ramming mixes and mortars is discussed in this paper. Effects of temperature, density and the joint thickness are analysed. The data are obtained using uni-axial tests with lateral constraints, maximally representative for the service conditions. The results indicate that above 700°C for the ramming and in the range 300–1000°C for the mortar, the joints are to develop stiffness of the same order of magnitude as the surrounding refractories. Viscosity effects are expected below 50°C and above 1000°C for ramming and mortar, respectively. The deviation from the specified density and the joint thickness is to affect the joint stiffness in the whole service temperature range.

Furnaces are useful for melting different materials for casting process. In this research paper, we had done advanced heat transfer analysis of induction furnace wall made of silica ramming mass using explicit finite difference method. We have divided actual geometry of furnace refractory wall into 14 elements and 24 nodes. We have derived explicit finite difference equations for all 24 nodes. We have calculated temperature distribution and thermal stress distribution for all different nodes with respect to time. We have plotted graphs for maximum temperature v/s time and maximum stress v/s time. We found that results indicate the effect of thermal fatigue in the induction furnace wall for silica ramming mass. The analysis is very helpful in understanding how thermal fatigue failure of refractory wall happens.

The authors compare the technological capabilities of puncture, ramming and their combination in horizontal hole-making in soil. The test data on the hole-making tool–soil interaction are presented for the three methods. It is efficient to combine these methods to enhance performance of hole-making.

Bighorn sheep (Ovis canadensis) routinely experience violent impacts to the head as part of intraspecific fighting. Dynamic 3D finite element models of the skull and horns of a male bighorn sheep were developed to gain an understanding of the roles that the horn and bone materials and structure play in absorbing the impact that occurs during ramming. The geometry and volume mesh of the model were derived from CT scan images. The models included the horn, bony horn core, and bone of the skull. The horn core fills a portion of the hollow horn and consists of a thin cortical bone shell filled with foam-like trabecular bone. Two modified models were also created: one with the distal half of the horn length removed to assess the effects of the tapered spiral geometry of the horn, and one with the internal trabecular bone material of the horn core removed. The trabecular bone material stored three times more strain energy during impact than the horn material in the intact model. Removing half of the horn length had the effect of increasing translational accelerations in the brain cavity by 49%. Removing the trabecular bone in the horn core resulted in a 442% increase in rotational accelerations within the brain cavity. These findings support the investigation of novel bioinspired materials and designs that could be used in mitigating brain injuries and in other applications involving high-impact collisions. Statement of Significance Bighorn sheep routinely experience violent impacts to the head and horns without apparent negative consequences to the brain or horns. A portion of the horn is filled with a thin cortical bone shell containing foam-like trabecular bone. We developed novel dynamic finite element models of the skull and horns of bighorn sheep to gain an understanding of the roles that the horn and bone materials play in absorbing the impact that occurs during ramming. The study revealed that both horn and bone materials and the structures made from these materials (i.e., tapered spiral horns and foam-like trabecular bone struts) are important for absorbing impact energy and reducing brain cavity accelerations.

ANNOTATIONThis article proposes an approach to the prediction of stress state and assessing the strength of a circular tunnel lining and the surrounding rock mass under construction near the production used by the micro-tunneling technology of pipe ramming. The basis of this method is an analytical solution of the corresponding plane problem of elasticity theory.

Recently, the research activities by domestic and overseas researchers using the Korean ice-breaking research vessel, ARAON have been actively conducted. The ARAON regularly operates for research activities in the Antarctic and the Arctic Ocean every year. She conducts many scientific and engineering tasks including ice load measurement, investigation of the properties of material strength for sea ice, and icebreaking performance test during her voyages. Such tests provide important data for studying icebreaker. Ice-breaking mode is determined by conditions of sea ice and ice field, and it is divided into ramming and continuous icebreaking. When the icebreaker meets thick ice or icebergs, the ramming is conducted. At that time, the ship speed is generally slower than that of the continuous icebreaking. The ARAON conducted icebreaking performance tests at the Amundsen Sea in Antarctica in 2012. Many strain data were measured in the ramming and the continuous icebreaking. This study was based on the strain gauge signals measured by the ARAON during the research voyage in 2012 in the Antarctic and 2010 in the Arctic. The signals measured from repetitive ramming under the heavy ice condition in 2012 in the Antarctic Ocean were classified into the five profiles. And the classified ice load signals were analyzed with a focus on raising time, half-decaying time and total time duration. Also, the signals measured from continuous icebreaking in 2010 in the Arctic Ocean were analyzed in the same way as the ramming data. Finally, the time histories of ice load signals were summarized from the viewpoint of speed change at the time of ice load, and two data sets were compared.

Transendothelial migration (TEM) of lymphocytes and neutrophils is associated with the ability of their deformable nuclei to displace endothelial cytoskeletal barriers. Lamin A is a key intermediate filament component of the nuclear lamina which is downregulated during granulopoiesis. When elevated, lamin A restricts nuclear squeezing through rigid confinements. To determine if the low lamin A expression by leukocyte nuclei is critical for their exceptional squeezing ability through endothelial barriers, we overexpressed this protein in granulocyte-like differentiated HL-60 cells. A 10-fold higher lamin A expression did not interfere with chemokinetic motility of these granulocytes on immobilized CXCL1. Furthermore, these lamin A high leukocytes exhibited normal chemotaxis towards CXCL1 determined in large pore transwell barriers, but poorly squeezed through 3-μm pores towards identical CXCL1 gradients. Strikingly, however, these leukocytes successfully completed paracellular TEM across inflamed endothelial monolayers under shear flow, albeit with a small delay in nuclear squeezing into their sub-endothelial pseudopodia. In contrast, CXCR2 mediated granulocyte motility through collagen I barriers was dramatically delayed by lamin A overexpression due to a failure of lamin A high nuclei to translocate into the pseudopodia of the granulocytes. Collectively our data predict that leukocytes maintain a low lamin A content in their nuclear lamina in order to optimize squeezing through extracellular collagen barriers but can tolerate high lamin A content when crossing the highly adaptable barriers presented by the endothelial cytoskeleton.

The correlation experiments between the thermal conductivity and linear expansion coefficient of ramming material and temperature variation were carried out under normal pressure. The difference correlations between the thermal conductivity and linear expansion coefficient of asphalt and resin combined with ramming material and the temperature variation are obtained by comparing and analyzing the experiment results, and the correlation formulas are given. Finding out the differences between them and discussing the correlation between thermophysical properties and heat transfer of BF lining in theory, can provide a theoretical basis for the BF longevity design.

A new methodology was proposed for the characterization of time-dependent behavior of materials in order to develop a constitutive model. The material used for the characterization was ramming paste, a porous material used in an aluminum electrolysis cell, which is baked in place under varying loads induced by the thermal expansion of other components of the cell. In order to develop a constitutive model representing the paste mechanical behavior, it was necessary to get some insight into its behavior using samples which had been baked at different temperatures ranging from 200 to 1000 °C. Creep stages, effect of testing temperature on the creep, creep-recovery, as well as nonlinear creep were observed for designing a constitutive law. Uniaxial creep-recovery tests were carried out at two temperatures on the baked paste: ambient and higher. Results showed that the shape of creep curves was similar to a typical creep; recovery happened and the creep was shown to be nonlinear. Those experimental observations and the identification of nonlinear parameters of developed constitutive model demonstrated that the baked paste experiences nonlinear viscoelastic-viscoplastic behavior at different temperatures.

In order to solve a problem that the running of ramming chain is unstable and master each order natural frequency and deformation characteristics of the chain, the method of theoretical calculation and finite element analysis with software ANSYS is used on the natural frequency of the calculation and analysis. By comparing the data obtained from two methods to verify the correctness of the finite element model, the model is used to analyze natural frequencies and corresponding vibration mode of the ramming chain. The results show that under the low order natural frequency, the main deformation of the ramming chain is the lateral bending, longitudinal bending and torsion deformation, so the results provide the basis to master the deformation of the chain.

Furnaces are most commonly used for melting of materials. Induction furnaces are more beneficial as no fuel is required. It is a problem to find life of Induction Melting Furnace wall under thermal fatigue. The induction melting furnace wall is made of silica ramming mass which is one kind of refractory material. The failure occurs due to cyclic thermal stresses. Temperature distribution and thermal stress distribution fields of the induction melting furnace refractory wall were calculated by using ANSYS finite element analysis software based on the physical description of its failure under thermal fatigue conditions. The thermal fatigue life of the refractory wall is required to be found out by means of thermal stresses created inside the refractory wall of induction melting furnace from modified S - log N Curve.

In order to analyse the influencing factors of projectile attitude angle and velocity in the ammunition ramming process, an ammunition ramming dynamics model has been established, and the structure parameters and the projectile forced state have been accurately described. MSC.ADAMS has been applied to carry out simulated analysis on a certain ammunition ramming process of the ramming mechanism, which disclosed the general rules of ammunition ramming movement and discussed the influences of size and position of ramming force on the consistency of ammunition ramming. With combined solutions of ADAMS and ISIGHT, optimizing calculation has been carried out on the parameters of the ramming mechanism, through which, it effectively lifted the collision problem of projectile and barrel in the ammunition ramming process, providing a theoretical support for the parameter design of the ramming mechanism.