Tank Displacement Research Articles

Dynamic Analysis of RCC Elevated Water Tank Considering Effect of Conventional and Composite Staging

The raised water tank is the most significant building for storing huge amounts of water at a certain elevation to distribute the water in the surrounding area for survival purposes and to develop pressure for the distribution system. As elevated tanks are commonly utilized in seismically active areas, their seismic design must be thoroughly examined. The sloshing of the water during an earthquake may be one of the most important aspects for specific proportions of the tank and construction. The fluid-structure interaction complicates the dynamic analysis of a liquid-filled tank. As a result, there is a need to concentrate on the seismic safety of lifeline structures in terms of seismic design systems that are both safe during earthquakes and can sustain higher design forces. In this study, an elevated water tank is analyzed under seismic loading by considering conventional RCC staging and composite staging. The main focus of the study was to reduce the damage to the water tank under dynamic loading and to know the effect of composite member staging on the design performance of the water tank. The results were collected in terms of maximum base shear, overturning moment, displacement of tank etc. After performing the study, it was seen that composite columns in the staging of overhead water tanks improve the performance under seismic loading and help to control the roof displacement of the overhead water tank due to more stiffness provided by composite columns.

The Consequences of Non-Uniform Founding of Concrete Tank in Weak Wet Subsoil

Abstract The article presents problem of non-uniform foundation of structures in weak wet subsoil. The problem is illustrated with the case study of two-chamber-reinforced concrete water tank constructed in 1920s of 20th century, which cracked during construction. Under part of foundation, where the peat was found, the concrete piles were introduced. The results of five-year measurement of crack widths with crack gauges and geodesic measurements of vertical displacement of tank were presented. These results indicate that the tank is not stable and part of broken tank supported on piles is movable. On the basis of the presented data, the general conclusions concerning the non-uniform founding of tanks are formulated.

Study of a New Type of Dangerous Goods Transport Vehicle Rear Protective Device

Aiming at the situation of the lack protection to the tank in domestic dangerous goods transport vehicle, a new rear protective device was designed for it. A dangerous goods tank truck rear-end finite element model was established by using finite element software Hypermesh and LS-DYNA under the relevant test regulations in GB11567.2-2001. And analysis the impact without new guard comparing with it by researching two index of tank displacement deformation and energy absorption. The simulation results show that the dangerous goods tank vehicle installed guardrails basically unharmed, and the guards state stability during the collision deformation, and its blocking effect and energy absorbency are also significantly improved, which can protect tank well in a collision.

Seismic Behavior Evaluation of Concrete Elevated Water Tanks

Elevated tanks are important structures in storing vital products, such as petroleum products for cities and industrial facilities, as well as water storage. These structures have various types and are constructed in a way that a greater portion of their weight is concentrated at an elevation much about the base. Damage to these structures during strong ground motions may lead to fire or other hazardous events. In this research, a reinforced concrete elevated water tank, with 900 cubic meters capacity, exposed to three pairs of earthquake records was analyzed in time history using mechanical and finite-element modeling techniques. The liquid mass of the tank was modeled as lumped mass known as sloshing mass, or impulsive mass. The corresponding stiffness constants associated with the lumped mass were determined depending upon the properties of the tank wall and liquid mass. Tank responses including base shear, overturning moment, tank displacement, and sloshing displacement were also calculated. Obtained results revealed that the system responses are highly influenced by the structural parameters and the earthquake characteristics such as frequency content.

SEISMIC BEHAVIOR ASSESSMENT OF CONCRETE ELEVATED WATER TANKS

Elevated tanks are very important structures and consist of various types. Water supply is vital to control fires during earthquakes. Also they are utilized to store different products, like petroleum supplies in cities and industrial zones. Damage to these structures during strong ground motions may lead to fire or other hazardous events. Elevated tanks should stay functional after and before earthquakes. However their dynamic behavior differs greatly in comparison with other structures. In this research, a sample of reinforced concrete elevated water tank, with 900 cubic meters capacity, exposed to three pair of earthquake records have been studied and analyzed in time history using mechanical and finite-element modeling technique. The liquid mass of tank is modeled as lumped masses known as sloshing mass, or impulsive mass. The corresponding stiffness constants associated with these lumped masses have been worked out depending upon the properties of the tank wall and liquid mass. Tank responses including base shear, overturning moment, tank displacement, and sloshing displacement have been calculated. Results reveal that the system responses are highly influenced by the structural parameters and the earthquake characteristics such as frequency content.

Study on Tank Capacity Table Measuring Model after the Storage Tank Displacement

All of the gas station has established underground storage tanks in accordance with the unified state standards. Due to the reasons such as deformation of foundation many tanks occurs the longitudinal tilt and lateral deflection changed after a period of time in use that lead to tank capacity charts to change. This paper solves the storage tank displacements recognition and capacity charts calibration by mathematical modeling method and MATLAB software. We study the calibration tank capacity charts when actual storage tank happen vertical or horizontal displacements on the basis of research on small elliptic cylinder oil tank.

On Displacement Identification of Storage Tank and Research and Application of Mathematical Model for Tank Gage Table Calibration

The issue under discussion in this paper results from a practical task faced with research institutions and manufacturers for gas station equipment, and will be divided into two parts: 1. In order to observe the impact of storage tank displacement on tank gage table, the author, on the premise of the displacements parameters, to detect the corresponding values of oil level and volume and analyze the law of change of the tank gage table through modeling and provided a revised tank gage table. The above belongs to direct problem. 2. Based on the data from practical detection, the paper will identify how the displacement occurred and the level of the displacement. Meanwhile, the measure and result of calibration will be offered. All the above belongs to inverse problem.

Effect of Earthquake Characteristics on Seismic Performance of RC Elevated Water Tanks Considering Fluid Level within the Vessels

The dynamic behavior of a liquid storage tank as a special structure differs from that of general structures. Important structures of cylindrical shape are used to store vital products, such as water and petroleum products, for cities and industrial facilities. Damage to these structures during a strong ground motion may lead to fire or other hazardous events. Liquid storage tanks are lifeline structures and strategically very important, since they have vital use in industries and nuclear power plants. In this research, an example reinforced concrete (RC) elevated water tank, with 900 cubic meters capacity, is studied under three pairs of earthquake records and analyzed in time history by using mechanical and finite element modeling techniques. The liquid mass of the tank is modeled as lumped masses known as sloshing mass, impulsive mass and rigid mass. The corresponding stiffness constants associated with these lumped masses are worked out depending upon the properties of the tank wall and liquid mass. Tank responses including base shear, overturning moment, tank displacement, and sloshing displacement under these three pairs of earthquake records are calculated, and then the results are compared and contrasted. Results show that the system responses are highly influenced by the structural parameters and the earthquake characteristics, such as frequency content.

Water Audit Encourages Residents to Reduce Consumption

The North Marin (Calif.) Water District (NMWD) conducted a free home water audit for randomly selected customers from single‐family detached homes. All were in the upper quartile of water use; i.e., residents used about 41 percent more water than was used in the average single‐family home in the service area. At the time of the study, because of publicity about drought in the region, most households had reduced water consumption. For this reason, NMWD used a control group so it could isolate water saved by the audit program. The audit included an interview about patterns of water use, leak identification and repair, installation of low‐flow shower heads and toilet tank displacement devices, evaluation of lawn irrigation practices and recommendation of an irrigation schedule, and distribution of free publications and promotional items. Average annual use declined significantly after the audit, about 16 percent for the sample group and 11 percent for the control group. The difference, or 4.6 percent (9,188 gal), could be attributed to the audit project. Of this amount, 7,270 gal were estimated as being saved inside the home. Only 1,918 gal (less than 21 percent) were calculated as being saved outside the home, far less than NMWD had expected.

Earthquake response of sea-based storage tanks

An effective method for the linear analysis of dynamic response of submerged underwater oil storage tanks resting on a horizontal seabed to horizontal earthquake excitations is presented. The tank is axisymmetric in shape, has a flexible wall/roof, and is filled with oil and water. A general hybrid-finite element solution procedure has been formulated, wherein the tank structure, the interior fluids, as well as the near-field of the exterior water region are discretized into a toroidal finite-element network. The tank displacement is calculated as a superposition of the first few modes of the structure's free vibration. Contribution from the hydrodynamic interaction to the coupled motion is obtained by solving the Laplace equation with the appropriate boundary conditions, which includes a matching to the exterior far-field pressure (analytic) representation to simplify the computation process. The effects of fluids surrounding and inside the tank are studied. It is demonstrated that these effects have, in general, a significant impact on the tank earthquake response analysis. A comprehensive and predictive computer program for use in such tank response analysis has been developed for engineering applications.