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The purpose of this study is to simulate the tensile and shear types of fractures using the mixed fracture criteria considering the energy evolution based on the dual bilinear cohesive zone model and investigate the dynamic propagation of tensile and shear fractures induced by an impact load in rock. The propagation of tension and shear at different scales induced by the impact load is also an important aspect of this study.

In this study, based on the well-developed dual bilinear cohesive zone model and combined finite element-discrete element method, the dynamic propagation of tensile and shear fractures induced by the impact load in rock is investigated. Some key technologies, such as the governing partial differential equations, fracture criteria, numerical discretisation and detection and separation, are introduced to form the global algorithm and procedure. By comparing with the tensile and shear fractures induced by the impact load in rock disc in typical experiments, the effectiveness and reliability of the proposed method are well verified.

The dynamic propagation of tensile and shear fractures in the laboratory- and engineering-scale rock disc and rock strata are derived. The influence of mesh sensitivity, impact load velocities and load positions are investigated. The larger load velocities may induce larger fracture width and entire failure. When the impact load is applied near the left support constraint boundary, concentrated shear fractures appear around the loading region, as well as induced shear fracture band, which may induce local instability. The proposed method shows good applicability in studying the propagation of tensile and shear fractures under impact loads.

The proposed method can identify fracture propagation via the stress and energy evolution of rock masses under the impact load, which has potential to be extended into the investigation of the mixed fractures and disturbance of in-situ stresses during dynamic strata mining in deep energy development.

The purpose of this paper is to analyze the force and basic rating life of angular contact ball bearings of RV reducer under the actual operating condition.

Force analysis of angular contact ball bearing under the actual operating condition, calculate the axial, radial load and internal load distribution, calculate the basic rating life of angular contact ball bearing under variable load conditions.

The external load has a great influence on the radial load of angular contact ball bearing, further affecting the basic rating life of angular contact ball bearing, which is a great influence on the overall life of RV reducer under the condition of high frequency and heavy load.

This paper provides important ideas for the design and manufacture of RV reducer in theory and experiment technology.

The purpose of this research is to automate the operations and real time monitoring and controlling of a marine loading arm.

A generic control strategy to automate the operation of manually controlled marine loading arms has been developed. This strategy employs state of the art, industry standard position sensors, PLC systems, interactive human machine interface (HMI) and integrates fail‐safe operation and emergency shutdown procedures.

This approach satisfies all the industry safety regulations and liminates the possible risks and/ or spurious trips during product loading. The overall engineering process is simpler, easier to implement and manage due to the fact the industry standard equipment and design tools have been used. Using this generic strategy, manually operated marine loading arms can be automated for effective monitoring and controlling purposes.

It is expected that engineers around the world can benefit by this approach and will be able to design similar control equipment to automate the functionality of loading arms in their organizations.

This work is the authors' own. Thoughts and designs belong to them and the ideas presented are completely original, developed, implemented and tested by them over years.

TO establish the strength and stiffness of certain types of structure it is necessary to use a large displacement theory, i.e. one in which allowance is made for the redistribution of the loading effects as a consequence of the deformation produced by the loads. The post‐buckling behaviour of panels, cylinders and other types of structure under compressive endloads require such a theory and another important category is constituted in thin plates under normal pressure, the pressure being partly resisted by tensions in the plane of the plate, in the way that membranes resist pressure, and partly by the bending resistance or stiffness of the plate.

The purpose of this paper is to reveal the characteristics of hydrodynamic load capacity and torque transferred by oil film with variable viscosity, and the effect of groove number, width and depth on the hydrodynamic load capacity and torque transfer.

The radial temperature of friction pair and viscosity of YLA‐N32 hydraulic oil were measured through experiments, and a viscosity‐diameter expression was deduced using polynomial fitting method. Analytical expressions for hydrodynamic load capacity and torque of the oil film were deduced based on hydrodynamic lubrication theory.

The investigation shows the hydrodynamic load capacity and transferred torque with variable viscosity are much less than that with constant viscosity. Load capacity increases with the increase of groove depth which is the most significant influence factor, while it has the least influence on torque. Groove width has great influence on load capacity and torque. The load capacity increases with the increase of groove width; contrarily, torque decreases with the increase of groove width. Groove number has little influence on load capacity, while it has great influence on torque. The torque decreases with the increase of groove number.

In this paper, analytical solutions for hydrodynamic load capacity and torque of the oil film with variable viscosity are deduced. The paper reveals the relationship between hydrodynamic load capacity, torque transfer and groove number, width and depth.

In many coastal areas where there are problematic soils, pavement construction on the soil is difficult because of the low shear strength and high consolidated. Also, given that the container terminals constitute more than 70% of the port area and as pavement in these areas is subject to heavy loads due to the long-term container storage, wheels of transport and movement equipment, the pavement must tolerate a distributed loading of at least 4 ton/m² in accordance with the type and weight of the containers imposed on the pavement. This study aims to investigate a variety of common pavement designs in coastal areas of southern Iran. The pavement type and characteristics of the subgrade layers are the same for each port; the thickness of different pavement layers is designed.

Due to problematic soil in the pavement subgrade, heavy and long-term container loading and the associated equipment, port pavement enjoys great importance.

The designed pavements are modeled by ABAQUS finite element software. The pavements are subject to a static load imposed by the corner casting container and resulted a distributed load 4 tons/m². The results from data analysis show that the concrete block pavements influenced by the containers static loads of 3%–20% have less vertical displacement on the subgrade than other pavements (rigid and flexible).

This paper is modeling 3 port pavement in Iran. Based on field evaluation and simulation actual loading on pavement.

STRUCTURAL engineers have always been accustomed to think of the strength of a structure in terms of gradually applied, or “static”, loading. It was natural, therefore, that when strength tests were first made on aeroplane structures, the primary object was to find the load that, when gradually applied to the structure, just broke it. This “ultimate” load was easy to determine, because when it was reached the structure collapsed and refused to carry any more load. At a later stage attempts were made to define a “proof” load at which the structure, because of its deformation or other damage, just ceased to be regarded as airworthy. This proof load was a much vaguer load to determine experimentally; how long should it be left on the structure, should it be applied more than once, who should be regarded as competent to pronounce on the airworthiness of the deformed structure, and should the airworthiness be judged when the structure is actually underload or after the load is removed, were all difficult questions to answer. As a result, in spite of an increasing realization of the relatively greater importance of the proof load, or at least of some comparable concept, in practice reliance has continued to be placed on measurements of ultimate load.

This paper aims to focus on establishing the bond-slip constitutive relation of mortar anchor under high loading rates by the dynamic pull-out test.

Self-made specimens were made for the dynamic pull-out test to explore the bond performance of mortar anchor, and the bond-slip constitutive relation of mortar anchor under high loading rates was established according to the analysis of test data.

During the loading process, the position of the peak bond stress was observed to translate to the free end. The bearing capacity of the mortar anchor was enhanced to some extent due to the increase of the loading rate.

The bond-slip constitutive relation of mortar anchor under high loading rates was established with the introduction of the position function and dynamic-load expanded coefficient.

Design engineers use the term load path to describe, in general terms, the way in which loads path through a structure from the points of application to the points where they are reacted. In contrast, stress trajectories are more clearly identified by the direction of the principal stress vectors at a point. The first author proposed a simple definition of the term load path in 1995 and proposed procedures to determine load paths from two‐dimensional finite element solutions. In this paper, the concept of load paths will be further explored and related to stress trajectories and Michell structures. The insight given when determining the load transfer near a pin‐loaded hole will be demonstrated. In addition a cantilevered beam will be considered and an introduction to plotting load paths in three‐dimensional structures is given.

The purpose of this paper is to investigate the fatigue crack growth (FCG) under random loading using analytical methods.

For this purpose, two methods of cycle-by-cycle technique and central limit theorem (CLT) were used. The Walker equation was used to consider the stress ratio effect on the FCG rate. In order to validate the results in three random loading group with different loading levels and bandwidths, the results of the analysis, such as the mean lifetime of the specimen and the average crack length were compared with the test results in terms of the number of loading cycles.

The comparison indicated a good agreement between the results of the analysis and the test. Further, the diagrams of reliability and the probability of failure of the specimen were obtained for each loading group and were compared together.

Applying the cycle-by-cycle and CLT methods for the calculation of fatigue reliability of a CT specimen under random loading by the Walker equation and comparing their results with each other is not observed in other researches. Also in this study, the effect of the loading frequency bandwidth on lifetime was studied.