International Core Journal of Engineering 2020-26 | Page 56

calculation, which is based on the evaluation of the model.
wall may enter the unstable state and induces "Elephant
Foot Buckling", which leads to the loss of the normal
bearing capacity of the wall panel. This is also a problem of
close attention in the operation of storage tanks.
V. C ONCLUSION
In this paper, the Fourier decomposition method is used
to deal with the measured settlement data of the foundation,
and the finite element model of three kinds of storage tanks
is established. The structural response of the storage tank
under the condition of foundation settlement is obtained,
and the three models are evaluated. The main conclusions
are made.
In view of the above parameters closely related to tank
safety, the specific calculation results of the three models
are compared, as shown in Table IV.
T ABLE IV R ESULT COMPARISON OF THREE MODELS
Model number
Maximum Mises stress/MPa
Maximum radial
displacement/m
Maximum vertical
compressive stress /MPa
Calculation time/min
1
340
0.205 2
344
0.178 3
247
0.161
342 205 217
6 30 120
1) After settlement of the foundation, the stress state of
the tank's large-angle welds and the bottom of the tank wall
is relatively dangerous, and failure may occur. This requires
the attention of field operators.
2) Deformation of the storage tank after foundation
settlement occurs in different degrees, which may lead to the
phenomenon of chuck chucking and even tearing of the tank
wall. Therefore, it is necessary to monitor the deformation
of the tank wall.
It can be seen from Table IV that there are some
differences in the numerical results of the three models. In
general, the results of the first model are most conservative.
At the same time, table IV also compares the computation
time of the three models. From the point of view of time
efficiency, the first model has great advantages. In the
process of establishing the finite element model of tank, the
interaction between the bottom of the tank and the soil of
the foundation is more close to the actual situation, but the
contact element will have a great influence on the
convergence of the model. It is easy to cause convergence
and even no convergence. Even if the result is convergent,
the computation time is relatively long. Moreover, the
contact element is more advantageous in the simulation
dynamic process. This paper studies the static state of the
storage tank after the settlement of the foundation. It is
enough to simulate the interaction between the bottom and
the soil by the way of the common node connection. On the
basis of the typical thin shell structure characteristics of the
tank wall, the calculation time required by the shell element
simulation is shorter than the solid element on the basis of
the calculation precision. Therefore, considering the
reliability of calculation results and the efficiency of
computation time, the first model is more applicable.
3) Taking into account the reliability of the calculation
results and the efficiency of the calculation time, in the three
storage tank models established, tanks are simulated using
shell elements, and tank models with the tank joints and
foundations connected to the common nodes which have the
best application value.
A CKNOWLEDGMENT
This work is supported by the national key research and
development program of China “Typical storage of
dangerous chemicals safety warning and protection
integration key technology research and application
demonstration (2016YFC0801200)”.
R EFERENCES
[1]
[2]
[3]
Model1
Model2
Model3
[4]
[5]
[6]
[7]
Radial displacement(m)
[8]

Fig.3 Radial displacement distribution along height of storage tank
Of course, in order to provide guidance and reference for
the actual project, it is necessary to compare the actual
measurement results with the results of the model
[9]
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