Loss Of Carrying Capacity Research Articles

Retraction Note: A model of economic loss of environmental carrying capacity caused by flood disasters in urban tourism areas

In the research on the economic loss of the carrying capacity of the tourism industry caused by flood disasters, some domestic and foreign scholars have conducted many years of research and have achieved certain results. The most commonly used model at present is mainly based on the historical data of the local urban tourism industry and calculates the economic loss of the environmental carrying capacity of the urban tourism area based on aquatic elements, submersion time, etc. However, although the model can provide some help, it still has shortcomings. The economic loss predicted by the model is quite different from the actual loss. In view of this situation, a model of the economic loss of the environmental carrying capacity of urban tourist areas due to flooding is designed to provide technical support for the assessment of the economic loss of the environmental carrying capacity of urban tourist areas. In this context, this article combines early warning theory, sustainable development theory, urban biology theory, urban environmental theory, and urban function and design planning theory into the economic loss model of environmental carrying capacity based on the research of relevant experts. Experts at home and abroad have used system dynamics simulation methods to establish environmental carrying capacity economic loss models based on the research results of domestic and foreign tourism environmental carrying capacity to study the environmental carrying capacity of coastal areas in our country. Based on the research results, it puts forward relevant suggestions to improve the environmental carrying capacity of coastal cities in our country, optimizes the early warning system of coastal cities’ environmental carrying capacity, and relieves the environmental pressure of coastal scenic spots, thereby promoting the tourism development, economic development, urban planning and environmental protection for coastal scenic spots.

RETRACTED ARTICLE: A model of economic loss of environmental carrying capacity caused by flood disasters in urban tourism areas

In the research on the economic loss of the carrying capacity of the tourism industry caused by flood disasters, some domestic and foreign scholars have conducted many years of research and have achieved certain results. The most commonly used model at present is mainly based on the historical data of the local urban tourism industry and calculates the economic loss of the environmental carrying capacity of the urban tourism area based on aquatic elements, submersion time, etc. However, although the model can provide some help, it still has shortcomings. The economic loss predicted by the model is quite different from the actual loss. In view of this situation, a model of the economic loss of the environmental carrying capacity of urban tourist areas due to flooding is designed to provide technical support for the assessment of the economic loss of the environmental carrying capacity of urban tourist areas. In this context, this article combines early warning theory, sustainable development theory, urban biology theory, urban environmental theory, and urban function and design planning theory into the economic loss model of environmental carrying capacity based on the research of relevant experts. Experts at home and abroad have used system dynamics simulation methods to establish environmental carrying capacity economic loss models based on the research results of domestic and foreign tourism environmental carrying capacity to study the environmental carrying capacity of coastal areas in our country. Based on the research results, it puts forward relevant suggestions to improve the environmental carrying capacity of coastal cities in our country, optimizes the early warning system of coastal cities’ environmental carrying capacity, and relieves the environmental pressure of coastal scenic spots, thereby promoting the tourism development, economic development, urban planning and environmental protection for coastal scenic spots.

Functional materials under elasto-plastic deformation

A theoretical study of the factors affecting the workpiece accuracy under conditions of local plastic deformation has been carried out. The study has shown that when a two-support workpiece is bent by the force applied in the center along its length, plastic deformation occurs only at 1/3 of its length, and 2/3 remains under the elastic deformation. The paper analyzes the technologies and features of transient local plastic deformation, the factors influencing geometry fidelity are determined. The author gives the load function values under which the elastic deformation occurs as well as the carrying capacity loss load for the ideally plastic material unhardened. The function for calculating the values of elastic and plastic deformation zones is determined, which makes it possible to eliminate the need for additional calculations of the plastic deformation zone boundaries.

Damage assessment of channel section columns subjected to uniform compression

The paper presents the failure analysis of compressed channel section profile made of GFRP material. Three symmetrical arrangements of layers were considered: [90/0/90/0]s, [90/-45/45/0]s, [45/-45/90/0]s. In order to characterize the failure process, visual inspection, ultrasonic phased array, non-destructive testing and computer microtomography were used. Damage analysis based on studies of external and internal damage of investigated structure allowed for identification of characteristic failure modes and mechanisms. It was shown that the dominant form of destruction in the quasi-orthotropic system are matrix cracks coupled with the presence of extensive delamination while in quasi-isotropic systems more concentrated damage was noticed, in which the cracking/rapture of fibers localized in the column’s corners determined the initiation of the failure mechanism and the carrying capacity loss. In addition, it was noted that the fiber directions of the outer layers determined the directions of matrix cracks and delamination propagation.

Optimization study on roof break direction of gob-side entry retaining by roof break and filling in thick-layer soft rock layer

This paper proposes gob-side entry retaining by roof break and filling in thick-layer soft rock conditions based on the thick-layer soft rock roof strata migration law and the demand for non-pillar gob-side entry retaining projects. The functional expressions of main roof subsidence are derived for three break roof direction conditions: lateral deflection toward the roadway, lateral deflection toward the gob and vertically to the roof. These are derived according to the load-bearing boundary conditions of the main roadway roof stratum. It is concluded that the break roof angle is an important factor influencing the stability of gob-side entry retaining surrounding rock. This paper studies the stress distribution characteristics and plastic damage scope of gob-side entry retaining integrated coal seams, as well as the roof strata migration law and the supporting stability of caving structure filled on the break roof layer at the break roof angles of -5°, 0°, 5°, 10° and 15° are studied. The simulation results of numerical analysis indicate that, the stress concentration and plastic damage scope to the sides of gob-side entry retaining integrated coal at the break roof angle of 5° are reduced and shearing stress concentration of the caving filling body has been eliminated. The disturbance of coal mining to the roadway roof and loss of carrying capacity are mitigated. Field tests have been carried out on air-return roadway 5203 with the break roof angle of 5°. The monitoring indicates that the break roof filling section and compaction section are located at 0-45 m and 45-75 m behind the working face, respectively. The section from 75-100 m tends to be stable.

Analysis of locally loaded steel plate girders: Model for patch load resistance

The paper deals with the problem of ultimate load capacity of thin-walled steel I-girders under the patch load which acts in the web plane of the girder. It considers the patch load type “a” according to EN1993-1-5. The analysed problem is very complex with the girder carrying capacity loss due to buckling of the web under the loaded flange. An experimental research of twelve plate steel girders subjected to patch loading is presented. The mathematical model for calculating ultimate load capacity of thin-walled steel I-girder under the patch load is proposed. Experimentally obtained ultimate loads and ultimate loads calculated by EN1993-1-5 are compared with those calculated by the proposed model. Experimental database consists of 52 tests from the experimental researches which were done at the Civil Engineering Faculty, University of Montenegro.

Closed system of limit equilibrium equations for axisymmetric shells

We consider rigid-plastic axisymmetric shells and use methods of control theory to construct the carrying capacity loss condition for such shells in formalized form.

Deformation stability of solids with cracks or inclusions

The method of calculating the limiting state of solids built on known elasticity relations is proposed to describe stable and unstable deformation of the defect-containing material. The basis for the method is evaluating the rigidity distribution over the body volume. The limiting state of the body is associated with the total negative rigidity of the body and loading system. An increase in damaged area sizes that are much smaller than component sizes is shown to result in stability and carrying capacity losses of the whole component at a certain rigidity of this area. Rigidity calculations for the bodies in the form of a sphere, cylinder or plate with inclusions as well as a crack-containing plate are cited.

Experimental research on I-girders subjected to eccentric patch loading

Abstract This paper presents the results of the experimental research performed on the thin-walled I-profiles subjected to patch loading. The experiment was divided into two phases. During the first one the behaviour of girders subjected to loading in the plane of the web was studied, and during the second phase, girders subjected to loading showing certain eccentricity in relation to the web plane were analysed. Thirty-six tests were performed. This paper analyses the results of girders under eccentric loading. The girders were tested to final collapse. The failure load is smaller under certain conditions than in cases with concentric load. Girder collapse form differs considerably from the collapse form of the concentrically loaded beams. Carrying capacity loss in the case of concentrically loaded girders is due to web buckling, while in the case of eccentrically loaded beams we consider the problem of carrying capacity loss due to local elasto-plastic bending. During the process of load increase the most evident deformation is flange warping accompanied by gentle web bending, which follows flange deformation. Flange warping and web bending grow until final collapse of girder. The most important question which is to be investigated in the future is under what conditions and what combinations of different parameters and eccentricity values the collapse form will be of the same kind as with concentrically loaded girders.

Discussion-Report on Loss in Carrying Capacity of Water Mains

Discussion-Report on Loss in Carrying Capacity of Water Mains