Damage To Tanks Research Articles

ANSYS-Based Structural Analysis Study of Elevated Spherical Tank Exposed to Earthquake

Damage of elevated tanks during earthquakes can jeopardize the supply of drinking water and causes significant economic losses. Therefore, seismic analysis of tanks containing liquids requires special consideration. Knowledge of liquid hydrodynamic pressures developed during an earthquake is important for tank design. This paper aims to verify the dynamic reaction of structural systems of spherical elevated steel tanks containing water, and determine the natural frequencies that contribute to the physical response, as well as seismic analysis of the tank. A three dimensional Finite Element Model was developed to identify the main parameters involved in this response for three different fullness ratio (0.00%, 53.30% and 71.11%) using the ANSYS software. The model was implemented and validated based on the results of a previously conducted experimental study. Moreover, it was analyzed under the impact of the most severe earthquake that Iraq was exposed to in 2017 with a magnitude of 7.2 on the Richter scale. The results showed a very good agreement in natural frequency with a discrepancy (root mean square error) of 2% (0.05 Hz), 6.9% (0.15 Hz) and 9.5% (0.2 Hz) for the fullness ratio 0%, 53.3% and 71.11%, respectively In addition, the selected element type and the method of analysis are applicable. Moreover, results of displacement and stresses from earthquake analysis indicated that the spherical tank could lose stability in time 1.4 seconds of the proposed time for the worst part of the earthquake, when displacement records highest values in the direction of earthquake for the tank body at chosen points in the top, middle, and bottom of the tank body which were almost equally at all cases proposed in this study.

Hybrid Bayesian network-based landslide risk assessment method for modeling risk for industrial facilities subjected to landslides

Industrialization exposes more petrochemical facilities in the slope-industrial interfaces (SIIs) to the impact range of landslides, demanding practical assessment approaches for addressing associated damage and its potential consequences. However, accurately predicting the expansion and upgrade of landslide hazards in industrial plants is challenging, involving a series of cascading-event trigger-response analyses. Accordingly, this paper develops a hybrid Bayesian network-based landslide risk assessment (HBN-LRA) model to evaluate the landslide risk on storage tanks in SIIs. This model decomposes the landslide risk into three submodules: slope stability, failure of targets, and proactive remedial measures and updates. It transmits the landslide risk through conditional dependence between subsystems. The results of applying the HBN-LRA model toward quantifying the landslide risk in a typical SII area indicate that the distance from the slope in the system risk factors directly determines storage tank damage. Landslide risk is sensitive to geological and geomorphic conditions, such as soil depth, cohesion, and unit weight; their relative importance all exceed 0.15. Tests on the case slope demonstrate that reducing the drainage paving distance from 10 to 8 m can improve slope stability by 50%. This result highlights the potential of the proactive remedial module in evaluating and designing slope drainage systems.

ANSYS-Based Structural Analysis Study of Elevated Spherical Tank Exposed to Earthquake

Damage of elevated tanks during earthquakes can jeopardize the supply of drinking water and causes significant economic losses. Therefore, seismic analysis of tanks containing liquids requires special consideration. Knowledge of liquid hydrodynamic pressures developed during an earthquake is important for tank design. This paper aims to verify the dynamic reaction of structural systems of spherical elevated steel tanks containing water, and determine the natural frequencies that contribute to the physical response, as well as seismic analysis of the tank. A three dimensional Finite Element Model was developed to identify the main parameters involved in this response for three different fullness ratio (0.00%, 53.30% and 71.11%) using the ANSYS software. The model was implemented and validated based on the results of a previously conducted experimental study. Moreover, it was analyzed under the impact of the most severe earthquake that Iraq was exposed to in 2017 with a magnitude of 7.2 on the Richter scale. The results showed a very good agreement in natural frequency with a discrepancy (root mean square error) of 2% (0.05 Hz), 6.9% (0.15 Hz) and 9.5% (0.2 Hz) for the fullness ratio 0%, 53.3% and 71.11%, respectively In addition, the selected element type and the method of analysis are applicable. Moreover, results of displacement and stresses from earthquake analysis indicated that the spherical tank could lose stability in time 1.4 seconds of the proposed time for the worst part of the earthquake, when displacement records highest values in the direction of earthquake for the tank body at...

Study of Reducing the Damage and Reuse of Waste Tanks in the Certej Mining Area

Abstract The Certej area is an area of gold mining activities with a history of several hundred years. The only activity with a significant share in the area was the mining activity, which provided the population of Certeju de Sus commune and its surroundings with the means necessary for a decent living. In the case of tailings dumps, the soil suffers a combined impact - by removing large areas of land from the natural circuit and by generating acidic water. The geology and morphology of the region, characterized by the existence of surfaces with different slopes, are natural causes that attribute different levels of vulnerability to land at the onset of degradation processes by erosion, landslides and excess moisture. All these bring limitations in the use of land on the main uses: agricultural, forestry, construction, etc. The paper aims to provide solutions for the reuse of these lands, their use by recultivation, the search for plant species adaptable to soil conditions. A relatively small number of species were determined on the tailings dumps in the studied area, the spontaneous vegetation is visibly stressed by the existing conditions. As such, the method of ecological reconstruction of freshly deposited tailings dumps by the method of forest recultivation is proposed.

Safety distances for storage tanks to prevent fire damage in Wildland-Industrial Interface

Wildfire occurrence frequency is increasing worldwide, generating more and more concern, especially in Wildland-Urban interfaces (WUI) and Wildland-Industrial Interfaces (WII) areas. Wildfires approaching WII can cause severe damage to people and industrial assets. In these scenarios, storage tanks present in industrial installations are among the most vulnerable pieces of equipment, since they are usually located in the proximity of the plant boundary. If hazardous substances are stored, tank damage caused by the fire can lead to loss of containment and trigger technological accident scenarios, escalating the consequences. Preserving the integrity of this type of equipment in case of wildfires is of paramount importance. The present study proposes a stepwise methodology for the evaluation of safety distances between storage tanks and vegetation that may be affected by a wildfire. According to the available data on the wildfire, on the lay-out and on the tanks that are likely to be affected, the methodology provides safety distances that may be applied to design fuel-reduced fringes around the industrial facility. The methodology proposed represents a quantitative tool for the calculation of safety distances that can guide industrial managers and assist regulators in the definition of more reliable standards. The comparison of the safety distances resulting from the present study with regulations and guidelines currently in use in different countries rises concern about the possible underestimation of required safety distances in the case of severe wildfires.

Seismic Analysis of RC Elevated Rectangular Water Tank using Various Staging Patterns

Elevated water tanks are the structures of greater importance which are considered as the main lifeline elements. Many displeasing experiences have taken place earlier due to the damage and collapse of elevated water tanks due to the occurrence of earthquakes. The reason behind the damage is lack of providing proper supporting system to the water tank to withstand the dynamic loads and also due to improper selection of staging. The main objective of the present study is to evaluate the seismic response of elevated rectangular water tank with different staging patterns and different water level conditions (full, half and empty). Four types of bracing systems of elevated water tank such as normal bracing, diagonal bracing, V bracing, and cross bracing are considered for the analysis with various water level conditions. A total of 12 combinations were analysed and base shear, base moment and roof displacement for the fixed models were calculated with SAP2000 v 20.0.0 software using Response Spectrum Method (RSM) and results are presented.

Numerical investigation on the difference of dispersion behavior between cryogenic liquid hydrogen and methane

The potential hazard of cryogenic and combustible liquid propellants (hydrogen and methane) leakage caused by spontaneous damage of tanks or rupture of pipelines is still a problem for both applications and human beings. Numerical simulations have been performed to predict the fuels’ leakage and dispersion behavior differences. Based on liquid hydrogen release tests conducted by the Health & Safety Laboratory (HSL), a mixture four-phase flow model considering the liquid hydrogen and air phase transitions has been developed. The liquid phase movements in the near field, combustible clouds and cold effect clouds movement in the far field were investigated. With Froude number increases from 0.47 to 3.72, liquid hydrogen represents a downward trend while liquid methane shows a downwind trend. For combustible clouds, the movements of hydrogen are larger than that of methane in both downwind and vertical direction on a quasi-stable state. For cold effect clouds, the dispersion of methane is greater than that of hydrogen in Froude number of 0.47, 0.93, 1.86, but then smaller in larger Froude number of 3.72.

Simulation of Fuel Storage Hazards Associated With Petroleum Refineries Tanks

Abstract Predicting of hazards associated with the damages of fuel storage tanks in petroleum refineries is critical in maintaining safety of the facilities. This study assesses the hazard of the refinery gasoline tank damage by augmented mathematical and semi-experimental methods. This research evaluates complete content release of the reservoir tank scenario in a given time, as the worst case. Environment conditions are evaluated as affecting factors on the progression of the scenario. Comparison between the results of numerical simulations for pool fire as well as vapor cloud explosion with the results of simulation based on empirical-mathematical models indicates noticeable differences between the results in the vicinity of the boundary conditions; however, with increasing the distance from the center of the accident point, this difference decreases markedly.

Investigation of Cylindrical Steel Tank Damage at Wineries during Earthquakes: Lessons Learned and Mitigation Opportunities

AbstractThe moment magnitude scale (Mw) 6.0 South Napa earthquake caused damage to stainless steel cylindrical tanks used for wine storage and fermentation. The damage observed to the tanks included local buckling of the tank walls, anchorage failure, and damage at the top of the tanks as a result of the catwalk system. Inspections of these tanks after the South Napa earthquake provided the motivation and the basis for investigating the seismic behavior of stainless steel cylindrical tanks used for liquid storage. This investigation focused on (1) the behavior of stainless steel cylindrical tanks in previous earthquakes around the world, and (2) research performed to mitigate this damage. The damage to cylindrical steel tanks after the South Napa earthquake was found to be identical to damage documented by postearthquake reconnaissance reports from around the world. Large-scale experimental research (by other researchers) has already demonstrated the inadequacy of cylindrical tank anchorage details for th...

Experimental study of slip-friction connectors for controlling the maximum seismic demand on a liquid storage tank

Previous investigations have demonstrated that strong earthquakes can cause severe damage or collapse of storage tanks. Theoretical studies by other researchers have shown that using energy-dissipating anchors can reduce the axial compressive stresses in the tank shell compared to the fully anchored case. Those studies have also shown that using energy-dissipating anchors can reduce the displacement of the tank compared to the unanchored case. However, there is no experimental work to validate the results obtained from these numerical studies. This paper reports on a series of experiments using a shake table on a scale model PVC tank containing water. A comparison of the seismic behaviour of a fully fixed base system (tank with anchorage), a system free to uplift (tank without anchorage) and a partially fixed system (tank with slip-friction connectors) is presented. The slip-friction connectors are calibrated by performing cyclic tests. The experiments were performed using recorded ground motion scaled to the New Zealand design spectra for two Wellington sites. Measurements were made of the axial compressive stresses in the tank shell and the horizontal displacement of the top of the tank. The experiments showed the beneficial effects of using slip-friction connectors in storage tanks, reducing the uplift displacement in comparison with an unanchored tank and reducing the axial stresses compared to a fully fixed tank. A numerical model is proposed which corroborates these results.

투과성 내부재가 설치된 사각형 탱크내의 슬로싱 현상에 대한 실험적 연구

A variety of inner baffles are often installed to reduce liquid sloshing and prevent tank damage. In particular, a porous baff le has a distinct advantage in reducing sloshing by changing the natural periods and dissipating the wave energy in a tank. In model tests, porous baffles with five different porosities were installed vertically in a l iquid tank under sway motion. The free surface elevations and pressures were measured using an image processing technique and a pressure gage for various combinations of baffle's porosity and submergence depth, and tank's amplitude and period. The experimental results were in good agreement with the analytic solutions (Cho, 2015), with the exception of a quantitative difference at resonant periods. The experimental results showed that the sloshing characteristics in a tank were closely dependent on both the porosity and submergence depth of the baffle, and the optimal porosity existed near P = 0.1275.

Risk Analysis Of Collision Between Passenger Ferry And Chemical Tanker In The Western Zone Of The Baltic Sea

Abstract This paper presents assumptions and process of the forming of a risk assessment model for collision between a passenger ferry departing from or approaching port of Świnoujście and a chemical tanker carrying a dangerous cargo. In order to assess navigational safety on the basis of data obtained from AIS system, were prepared probabilistic domains of ships, which made it possible to estimate number of navigational incidents as well as their spatial distribution, that consequently allowed to determine potentially dangerous areas. The next phase was formulation of a simulative model intended for the calculating of probability of collision between the ferry and chemical tanker as well as the determining of characteristic scenarios for such collision. This paper presents also an analysis of consequences of the collision with taking into consideration a damage of cargo tanks.

Potential Damages of Atmospheric Storage Tanks due to Volcanic Ash Aggregations in Presence of Water

Recent studies of the effects of the volcanic ash fallout on storage tanks have shown the potential causes of failure for both fixed and floating roof tanks. The vulnerability of these facilities has been defined through the estimation of threshold values of the ash load on their roofs and exceedance probabilities of these limits. It has been observed that the amount of the overhead on the roof is much greater when the ash is saturated with rain because of the formation of aggregates. This paper aims to analyse the influence of this phenomenon on the potential damage of tanks located in the area surrounding Mt. Etna.

Experimental study on sloshing in a tank with an inner horizontal perforated plate

Sloshing in a liquid tank may result in ship instability or structural damage. Inner structures are often used to restrain liquid sloshing and prevent tank damage. To increase energy dissipation and reduce the forces acting on structures, a horizontal perforated plate was designed and incorporated into a rectangular liquid tank in this study. Experimental studies were conducted, and a tank with an inner submerged horizontal perforated plate was excited under different amplitudes and frequencies. The free surface elevations on the side-walls and the resonant frequencies were carefully examined. The experimental results indicate that the horizontal perforated plate can significantly restrain violent resonant sloshing in the tank under horizontal excitation.

Accident Consequence Simulation Analysis of Pool Fire in Fire Dike

Pool fires are the most common of all process industry accidents. Pool fires often trigger explosions which may result in more fires, causing huge losses of life and property. Since both the risk and the frequency of occurrence of pool fires are high, it is necessary to model the risks associated with pool fires so as to correctly predict the behavior of such fires. In this paper, the petrochemical tank area of a chemical enterprise in Tianjin is selected as a study case, for the basic features of reserve materials and the specific circumstances of the storage tank area, hazard analysis and damage area of its pool fire in fire dike according to the model calculation and CFD simulation are discussed. The results showed that the strong thermal radiation of pool fire could destroy adjacent tanks, equipments, and public pipe, and even cause serious casualties within the scope of 28.46 meters. When the fire separation distance between tanks, tank and pipeline, tank and other buildings is more than 69.71 meters, the production equipment could not be damaged, and the production personnel inside could not be injured.

Comparison of the Operating Life of Tank Containers, Tank Vehicles and Rail Tank Cars for the Carriage of Dangerous Goods in Practice, Analysis of Causes of Damage

More than 400 Mt of dangerous materials are transported in Germany every year, of which 150 Mt are by road. Tank containers, tank vehicles and rail tank cars are used for the carriage of dangerous goods in large quantities. Data on the operating life of tanks are only available, in practice, to a minor degree. They are only partly published, mainly after accidents.The BAM-List - Requirements for Tanks for the Carriage of Dangerous Goods, which has compatibility evaluations of metallic and polymeric materials, has been the basis for substance-related prototype approvals for tank containers and portable tanks designed for the carriage of dangerous goods by the BAM since publication of the first edition in 1989. These data are also used for the approval of rail tank cars and road tank cars and are used as a source of knowledge not only in Germany but also worldwide. Tank leakages caused by tanks or rail tank cars being made of tank and sealing materials which are not resistant to the fill goods are avoided by using the material resistance data of the BAM.Corrosion damage is among the main causes of damage. Uniform and non-uniform area corrosion without mechanical stress in aqueous substances is one of the most frequent types of corrosion during the transport of chemicals in tanks. Much damage by pitting corrosion occurs during the transport of substances containing chlorides or substances which separate chloride ions in the presence of moisture. Operational stresses are caused by the effects of both the road and the dangerous goods being transported. Mechanical damage often results from long-term overstressing and occurs after longer operating times.Operational failures cause damage which may appear during the service of tank containers, road tank cars or rail tank cars. The damage results from the inattention of employees when opening and closing the valves. Traffic accidents also cause damage to tanks and frames.Many cases of damage are due to weld area cracks resulting from four basic errors in construction, material, manufacturing and operation. Manufacturing errors can be undetected and the starting point of cracks which only grow under service conditions.Manufacturing errors result from variations in measurement and design, fittings, state of surface (hardness, abrasiveness) and mechanical surface damage (scratches, cracks). Incorrectly welded joints and errors during mechanical deformation are typical mistakes when installing the component parts. Variations in the wall thickness or combinations of different materials lead to manufacturing errors too.A lot of tanks are not used for the transport of dangerous goods before the end of their service life as they do not fulfil the revised technical safety requirements in the Dangerous Goods Regulations.Predictions in the BAM-List based on literature data and corrosion test results are reflected in the service (operating) life. Rail tank cars made of carbon steel, for example, which are mainly used for the transport of petroleum products, can achieve a service life of 40 – 50 y.Rail tank cars produced of austenitic CrNi- or CrNiMo-steel can reach an operating life of at least 30 y, whereby the corrosiveness of the transport substances plays an important role.

Release of hazardous substances in flood events: Damage model for atmospheric storage tanks

The damage of storage tanks in flood events may lead to severe “natural-technological” (NaTech) accident scenarios due to the release of hazardous substances causing damage to people and environment. In the present study, damage of atmospheric storage tanks in floods was analyzed in detail. A mechanical damage model was developed and validated by available literature data on past accidents. Simplified correlations were then obtained to calculate the probability of loss of containment on the basis of severity parameters of the flood event. The tank vulnerability model was integrated in a comprehensive approach for the quantitative risk assessment of NaTech scenarios triggered by floods. A case-study was discussed to test the potentialities of the method.

一般産業施設の被害(TRANSLOG/J-RAIL共同特別企画)

A huge earthquake of Mw 9.0 hit the Tohoku district of Japan on March 11, 2011. The earthquake, which was named as "the 2011 Great East Japan Earthquake", caused serious damage to industrial facilities. Based on the damage investigations conducted by the JSME, the damage to the mechanical structures were due to the strong ground motion, soil deformation and tsunami. Many kinds of damage caused by strong motion, such as the damage at the base of machines, the failure of pipe supports, buckling of tanks and the failure of hook bolts were commonly observed. Soil deformation caused break of buried pipes and misalignment of gantry crane rails. The tsunami also caused various kinds of damage, such as broken equipment due to collisions with floating objects and damage of tanks due to water pressure. Power system damage caused by electrical short circuiting also occurred. Although the earthquake caused a great deal of damage, seismic measures taken before the earthquake could mitigate damage of some facilities. This paper provides an overview of the damage of industrial facilities caused by the 2011 Great East Japan Earthquake, their typical damage cases, and the effects of the earthquake resisting methods.

651 日本機械学会による機械設備等の地震被害調査活動

In the 2011 Great East Japan Earthquake, serious damage occurred in power plants and industrial plants due to the strong ground motion, soil deformation and tsunami. Many kinds of damage caused by strong motion, such as the buckling of tanks, the failure of hook bolts, or the falling of overhead cranes, and the dropping of over-hanging pipes were commonly observed. The tsunami also caused various kinds of damage, such as broken equipment due to collisions with floating objects and damage of tanks due to water pressure. Power system damage caused by electrical short circuiting also occurred. Although the earthquake caused a great deal of damage, seismic measures taken before the earthquake could mitigate damage of some facilities. This paper provides an overview of the damage of mechanical facilities caused by the 2011 Great East Japan Earthquake, their typical damage cases, and the effects of the earthquake resisting methods.

고압가스 연료탱크의 손상평가를 위한 음향방출 변수의 분석

본 논문은 자동차용 type II CNG 연료탱크의 손상평가를 위하여 파열시험 중 발생하는 음향방출 변수의 분석에 관한 연구이다. 음향방출 신호의 kaiser effect, felicity effect 및 creep effect의 관찰과 전체 hits에서 진폭 60dB이상의 hits가 차지하는 비율 계산으로 연료탱크의 손상도를 평가할 수 있었으며, 평균 rise time, 평균 진폭 및 평균 initial, reverbration 주파수를 분석함으로써 압력용기의 손상메커니즘을 추정하였다. This paper described analysis of acoustic emission parameter for the damage evaluation of type II vehicle fuel tank during fracture test. The observation of Kaiser effect, Felicity effect and creep effect is the means of damage evaluation method. It is possible to evaluate tank damage by the ratio of hit of over 60 dB and total hit. Damage mechanism of pressure tank can be estimated by analysis of average rise time, average amplitude.