(7) EFFECTIVENESS OF BRACING ARRANGEMENT IN IMPARTING STIFFNESS AGAINST LATERAL FORCES : Lateral Force Distribution in Continuous and Dispersed Elastic or Plastic Bracings in Three Dimentional Framed Structures using The Method of Difference Equations and Stress-Controlled Calculation

The purpose of this article is to contribute to a more comprehensive overview of the lateral force on tapered pistons. Numerical analyses are carried out to evaluate the lateral force on a piston; the flow rate through the clearance is also calculated. The range of parameters, namely, length-to-diameter ratio, the taper and the eccentricity, covers almost all the applications that appear in fluid power engineering. The pressure distribution obtained by difference equations is verified using an iteration convergence test. The lateral force is obtained applying Simpson’s integral to the obtained pressure. Using the dimensionless lateral forces obtained using finite mesh sizes, an evaluation of the dimensionless lateral force for an infinitely fine mesh size is made. The numerical results coincide well with experiments reported in the literature. An approximate function is shown by expressing the dimensionless force with an accuracy of about 3% for a region of the taper and the length/diameter ratio appearing frequently in practice. Four types of difference equations that are derived from the laminar flow equation are compared with respect to necessary iteration numbers and accuracy of the results.

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A Seismic Design Lateral Force Distribution Based on Inelastic State of Structures

Earthquake Spectra ◽

10.1193/1.2753549 ◽

2007 ◽

Vol 23 (3) ◽

pp. 547-569 ◽

Cited By ~ 94

Author(s):

Shih-Ho Chao ◽

Subhash C. Goel ◽

Soon-Sik Lee

Keyword(s):

Seismic Design ◽

Lateral Force ◽

Elastic Response ◽

Force Distribution ◽

Relative Distribution ◽

Inelastic Behavior ◽

Seismic Demands ◽

Framed Structures ◽

Dynamic Analyses ◽

Nonlinear Dynamic Analyses

It is well recognized that structures designed by current codes undergo large inelastic deformations during major earthquakes. However, lateral force distributions given in the seismic design codes are typically based on results of elastic-response studies. In this paper, lateral force distributions used in the current seismic codes are reviewed and the results obtained from nonlinear dynamic analyses of a number of example structures are presented and discussed. It is concluded that code lateral force distributions do not represent the maximum force distributions that may be induced during nonlinear response, which may lead to inaccurate predictions of deformation and force demands, causing structures to behave in a rather unpredictable and undesirable manner. A new lateral force distribution based on study of inelastic behavior is developed by using relative distribution of maximum story shears of the example structures subjected to a wide variety of earthquake ground motions. The results show that the suggested lateral force distribution, especially for the types of framed structures investigated in this study, is more rational and gives a much better prediction of inelastic seismic demands at global as well as at element levels.

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A proposal to determine the distribution of lateral forces from loaded recycled plastic drainage kerbs

SN Applied Sciences ◽

10.1007/s42452-020-04033-x ◽

2021 ◽

Vol 3 (2) ◽

Author(s):

Fin O’Flaherty ◽

Fathi Al-Shawi

Keyword(s):

Laboratory Test ◽

Detailed Analysis ◽

Test Data ◽

Lateral Force ◽

Measuring Device ◽

Test Methodology ◽

Lateral Forces ◽

Test Conditions ◽

Fit For Purpose ◽

Construction Product

AbstractThis study presents a detailed analysis of the lateral forces generated as a result of vertically applied loads to recycled plastic drainage kerbs. These kerbs are a relatively new addition to road infrastructure projects. When concrete is used to form road drainage kerbs, its deformation is minimum when stressed under heavy axle loads. Although recycled plastic kerbs are more environmentally friendly as a construction product, they are less stiff than concrete and tend to deform more under loading leading to a bursting type, lateral force being applied to the haunch materials, the magnitude of which is unknown. A method is proposed for establishing the distribution of these lateral forces resulting from deformation under laboratory test conditions. A load of 400 kN is applied onto a total of six typical kerbs in the laboratory in accordance with the test standard. The drainage kerbs are surrounded with 150 mm of concrete to the front and rear haunch and underneath as is normal during installation. The lateral forces exerted on the concrete surround as a result of deformation of the plastic kerbs are determined via a strain measuring device. Analysis of the test data allows the magnitude of the lateral forces to the surrounding media to be determined and, thereby, ensuring the haunch materials are not over-stressed as a result. The proposed test methodology and subsequent analysis allows for an important laboratory-based assessment of any typical recycled plastic drainage kerbs to be conducted to ensure they are fit-for-purpose in the field.

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Simultaneous Optimal Distribution of Lateral and Longitudinal Tire Forces for the Model Following Control

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.1850533 ◽

2004 ◽

Vol 126 (4) ◽

pp. 753-763 ◽

Cited By ~ 157

Author(s):

Ossama Mokhiamar ◽

Masato Abe

Keyword(s):

Lateral Force ◽

Longitudinal Force ◽

Equality Constraints ◽

Steering Wheel ◽

Slip Angle ◽

Force Distribution ◽

Distribution Method ◽

Tire Force ◽

Model Following Control ◽

Tire Forces

This paper presents a proposed optimum tire force distribution method in order to optimize tire usage and find out how the tires should share longitudinal and lateral forces to achieve a target vehicle response under the assumption that all four wheels can be independently steered, driven, and braked. The inputs to the optimization process are the driver’s commands (steering wheel angle, accelerator pedal pressure, and foot brake pressure), while the outputs are lateral and longitudinal forces on all four wheels. Lateral and longitudinal tire forces cannot be chosen arbitrarily, they have to satisfy certain specified equality constraints. The equality constraints are related to the required total longitudinal force, total lateral force, and total yaw moment. The total lateral force and total moment required are introduced using the model responses of side-slip angle and yaw rate while the total longitudinal force is computed according to driver’s command (traction or braking). A computer simulation of a closed-loop driver-vehicle system subjected to evasive lane change with braking is used to prove the significant effects of the proposed optimal tire force distribution method on improving the limit handling performance. The robustness of the vehicle motion with the proposed control against the coefficient of friction variation as well as the effect of steering wheel angle amplitude is discussed.

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SEISMIC LATERAL FORCE DISTRIBUTION FOR DUCTILITY-BASED DESIGN OF STEEL PLATE SHEAR WALLS

Journal of Earthquake and Tsunami ◽

10.1142/s1793431112500042 ◽

2012 ◽

Vol 06 (01) ◽

pp. 1250004 ◽

Cited By ~ 4

Author(s):

SWAPNIL B. KHARMALE ◽

SIDDHARTHA GHOSH

Keyword(s):

Steel Plate ◽

Shear Walls ◽

Shear Wall ◽

Lateral Force ◽

Performance Based Design ◽

Force Distribution ◽

Steel Plate Shear Walls ◽

Steel Plate Shear Wall ◽

Design Requirements ◽

Ductility Ratio

The thin unstiffened steel plate shear wall (SPSW) system has now emerged as a promising lateral load resisting system. Considering performance-based design requirements, a ductility-based design was recently proposed for SPSW systems. It was felt that a detailed and closer look into the aspect of seismic lateral force distribution was necessary in this method. An investigation toward finding a suitable lateral force distribution for ductility-based design of SPSW is presented in this paper. The investigation is based on trial designs for a variety of scenarios where five common lateral force distributions are considered. The effectiveness of an assumed trial distribution is measured primarily on the basis of how closely the design achieves the target ductility ratio, which is measured in terms of the roof displacement. All trial distributions are found to be almost equally effective. Therefore, the use of any commonly adopted lateral force distribution is recommended for plastic design of SPSW systems.

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