Multispan bridges with distributed deck and pier mass and pier‐flexure‐deck‐torsion coupling under transverse excitation—Analytical solution, parametric studies, design implications

Developing an analytical solution for the consolidation of unsaturated soils remains a challenging task due to the complexity of coupled governing equations for air and water phases. This paper presents an equal-strain model for the radial consolidation of unsaturated soils by vertical drains, and the effect of drain resistance is also considered. Simplified governing equations are established, and an analytical solution to calculate the excess pore-air and pore-water pressures is derived by using the methods of matrix analysis and eigenfunction expansion. The average degrees of consolidation for air and water phases and the ground surface settlement are also given. The solutions of the equal-strain model are verified by comparing the proposed free-strain model with the equal-strain model, and reasonably good agreement is obtained. Moreover, parametric studies regarding the drain resistance effect are graphically presented.

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An analytical solution for steady seepage into a defective pipe

Water Science & Technology Water Supply ◽

10.2166/ws.2017.168 ◽

2017 ◽

Vol 18 (3) ◽

pp. 926-935 ◽

Cited By ~ 2

Author(s):

Yao Tang ◽

Dave H. Chan ◽

David Z. Zhu ◽

Shuai Guo

Keyword(s):

Analytical Solution ◽

Groundwater Flow ◽

Pressure Distribution ◽

Pore Water Pressure ◽

Water Pressure ◽

Water Flow Rate ◽

Infiltration Rate ◽

Defect Position ◽

Water Head ◽

Parametric Studies

Abstract An analytical solution was proposed for the groundwater flow through a defective pipe, which can be used to estimate the water flow rate into the pipe and predict the pore water pressure distribution in surrounding soils. This analytical solution was verified by comparing with experimental results, and the predicted pressure distribution around the defective pipe is proved to be consistent with numerical simulations using the finite element method. From the parametric analysis, the infiltration rate increases as the defect position changes from top to bottom on the pipe, and the effect of defect position is not significant if the water head above the defect is 10 times greater than pipe radius. An approximated solution for estimating the groundwater flow infiltration rate through a circular orifice on the pipe is proposed as well. From the verification and parametric studies, this proposed analytical solution is proved to be an efficient approach for the estimation of groundwater infiltration through a defective pipe.

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Analytical Solution for Lateral-Torsional Buckling of Concrete-Filled Tubular Flange Girders with Torsional Bracing

Advances in Civil Engineering ◽

10.1155/2020/4340381 ◽

2020 ◽

Vol 2020 ◽

pp. 1-14

Author(s):

Yingchun Liu ◽

Zhaoming Hang ◽

Wenfu Zhang ◽

Keshan Chen ◽

Jing Ji

Keyword(s):

Analytical Solution ◽

Lateral Displacement ◽

Data Sets ◽

Torsional Angle ◽

The Finite Element Method ◽

Lateral Torsional Buckling ◽

Torsional Buckling ◽

Concentrated Load ◽

Buckling Strength ◽

Parametric Studies

Concrete-filled tubular flange girders have been used in bridges, and torsional bracings are widely used in them to increase the lateral-torsional buckling strength. This article proposes an analytical solution for the lateral-torsional buckling (LTB) of concrete-filled tubular flange steel girders with torsional bracing under a concentrated load. The modal trial functions of lateral displacement and the torsional angle are expressed by the first six terms of the trigonometric function. By introducing dimensionless parameters, the variational solution of energy for the buckling equation of the LTB of the girders is obtained, and the formula for the dimensionless critical moment of its LTB is derived using 1stOpt based on 32,550 data sets. Compared with the finite element method, the proposed critical formula is highly accurate and can be applied to engineering design. Finally, parametric studies were conducted on the effects of the stiffness of torsional bracing, the span of the girder, and the flange steel ratio.

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Analytical Solution for Stress and Displacement after X-Section Cast-in-Place Pile Installation

Mathematical Problems in Engineering ◽

10.1155/2013/937421 ◽

2013 ◽

Vol 2013 ◽

pp. 1-11

Author(s):

Hang Zhou ◽

Han Long Liu ◽

Gangqiang Kong ◽

Zhaohu Cao

Keyword(s):

Analytical Solution ◽

Field Test ◽

Horizontal Stress ◽

Soil Disturbance ◽

Test Results ◽

Pile Installation ◽

Present Solution ◽

Parametric Studies ◽

New Type ◽

Surrounding Soil

X-section cast-in-place (referred to as XCC) pile, which is one of new pile types developed by Hohai University, is widely used for pile foundation and pile-supported embankment over soft ground in China. However, little research has been carried out on this new type pile, especially the surrounding soil disturbance under XCC pile installation. This paper presents an analytical solution for estimating the horizontal stress and displacement of surrounding soil of XCC pile after XCC pile installation. The reliability and accuracy of the present solution are verified by comparing them with the field test results. Then, parametric studies, such as outsourcing diameter(a), open arc distance(b), open arc angle(θ), the undrained strength(Su), the limit pile cavity pressure(Plim), and the radius of the plastic zone(Rp), are discussed for the practice engineering design. The results show that the stress and displacement distributions of surrounding soil calculated by this paper are in agreement with field test results.

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WC8 - Parametric studies of pulsed HF lasers using transverse excitation

IEEE Journal of Quantum Electronics ◽

10.1109/jqe.1973.1077389 ◽

1973 ◽

Vol 9 (1) ◽

pp. 173-181 ◽

Cited By ~ 23

Author(s):

T. Jacobson ◽

G. Kimbell

Keyword(s):

Transverse Excitation ◽

Parametric Studies

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Transient Amplitude Amplification of Mistuned Blisks

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4030278 ◽

2015 ◽

Vol 137 (11) ◽

Cited By ~ 7

Author(s):

Marius Bonhage ◽

Linus Pohle ◽

Lars Panning-von Scheidt ◽

Jörg Wallaschek

Keyword(s):

Steady State ◽

Analytical Solution ◽

Traveling Waves ◽

Degrees Of Freedom ◽

Maximum Amplitude ◽

Steady State Solution ◽

Lumped Mass ◽

Mass Model ◽

Parametric Studies ◽

Lumped Mass Model

This article discusses the problem of exceeding amplitudes of mistuned structures caused by accelerated traveling waves type excitation, i.e., traveling waves with time variant frequencies. These waves cause resonance passages of, e.g., rotating structures. To calculate the resonance passage a semi-analytical solution is proposed. Thus, high accuracy is guaranteed. The topic of exceeding amplitudes is initially approached by studying a discrete lumped mass model with detuned parameters. It can be shown that under certain circumstances the maximum amplitude of the transient resonance passage is even higher than the maximum amplitude of the steady-state solution. To investigate this phenomenon on a real bladed disk, the number of degrees of freedom of the blisk is reduced using component mode synthesis (CMS). By applying the semi-analytical solution to the reduced model, the envelopes of the vibration during resonance passage can be calculated. Processing extensive parametric studies it can be pointed out under which circumstances the probability rises that higher maximum amplitudes occur during resonance passage compared to steady-state conditions.

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