Analytical Model for Estimation of Maximum Normal Stress in Steel Beam-Columns Based on Wireless Measurement of Average Strains from Vibrating Wire Strain Gages

2013 ◽  
Vol 28 (9) ◽  
pp. 707-717 ◽  
Author(s):  
Hong Min Lee ◽  
Se Woon Choi ◽  
Dong-jo Jung ◽  
Hyo Seon Park
Keyword(s):  
Normal Stress ◽  
Analytical Model ◽  
Steel Beam ◽  
Strain Gages ◽  
Vibrating Wire ◽  
Beam Columns ◽  
Maximum Normal Stress ◽  
Wire Strain ◽  
Wireless Measurement

Developing Large Slab Airport Runways for the Next Century

2019 ◽  
Vol 2673 (6) ◽  
pp. 524-535
Author(s):  
Stephen J. Roswurm ◽  
Chris Ramseyer
Keyword(s):  
Drying Shrinkage ◽  
Early Age ◽  
Strain Gages ◽  
Vibrating Wire ◽  
Type K ◽  
Wire Strain ◽  
Load Cells ◽  
Mineral Additive ◽  
Shrinkage Compensation ◽  
Airport Runway

The purpose of this research was to determine whether shrinkage-compensating concrete (SCC) made with Type K cement can create durable airport runways with fewer joints and reduced maintenance costs. The primary criterion examined was the ability of SCC to offset the effects of early-age drying shrinkage when the concrete is acted upon by external restraint. The interaction of restraint with SCC is important because restraint resists the expansive behavior that provides shrinkage compensation. Four sets of experiments were conducted, with increasing levels of Type K expansive mineral additive in each set. A set of test specimens consisted of four-inch diameter restrained columns. Each set consisted of three columns with varying degrees of stiffness in the restraint frame, including low, medium, and high-restraint stiffness. The medium-restraint column provides the theoretical response of new pavement cast against a mature slab, whereas the other two bracket the problem. The column specimens were instrumented using vibrating wire strain gages, which were embedded in the concrete, and load cells, which were affixed to the top of the columns. This research concludes that SCC can be effective even with a stiff boundary condition, and that SCC provides the potential for much longer-lasting airport runway slabs, as a result of reduced shrinkage and therefore fewer cracks.

An Analytical Model of Joint Contact

1990 ◽  
Vol 112 (4) ◽  
pp. 407-413 ◽  
Author(s):  
A. W. Eberhardt ◽  
L. M. Keer ◽  
J. L. Lewis ◽  
V. Vithoontien
Keyword(s):  
Stress Distribution ◽  
Normal Stress ◽  
Analytical Model ◽  
Contact Radius ◽  
Shear Stresses ◽  
Maximum Normal Stress ◽  
Calcified Cartilage ◽  
Joint Contact ◽  
Maximum Contact ◽  
Contact Parameters

The stress distribution in the region of contact between a layered elastic sphere and a layered elastic cavity is determined using an analytical model to simulate contact of articulating joints. The purpose is to use the solution to analyze the effects of cartilage thickness and stiffness, bone stiffness and joint curvature on the resulting stress field, and investigate the possibility of cracking of the material due to tensile and shear stresses. Vertical cracking of cartilage as well as horizontal splitting at the cartilage-calcified cartilage interface has been observed in osteoarthritic joints. The current results indicate that for a given system (material properties μ and ν constant), the stress distribution is a function of the ratio of contact radius to layer thickness (a/h), and while tensile stresses are seen to occur only when a/h is small, tensile strain is observed for all a/h values. Significant shear stresses are observed at the cartilage-bone interface. Softening of cartilage results in an increase in a/h, and a decrease in maximum normal stress. Cartilage thinning increases a/h and the maximum contact stress, while thickening has the opposite effect. A reduction in the indenting radius reduces a/h and increases the maximum normal stress. Bone softening is seen to have negligible effect on the resulting contact parameters and stress distribution.

scholarly journals Application of Vibrating Wire Strain Gages for Evaluating Main Pipeline Stress-Strain State

2021 ◽  
Vol 137 (6) ◽  
pp. 57-61
Author(s):  
А. А. Ignatik ◽  
Keyword(s):  
Strain Gage ◽  
Strain State ◽  
Strain Gages ◽  
Vibrating Wire ◽  
Stress Strain ◽  
Stress Strain State ◽  
Wire Strain ◽  
Wire Method ◽  
Different Diameters ◽  
Longitudinal Strains

The use of anti-turbulent and depressant additives makes it possible to increase the efficiency of oil pipelines trThis article considers the physical basis of the vibrating wire method of monitoring the stress-strain state of the pipe walls. A laboratory experiment performed on a stand for measuring pipe strains during its bending by vibrating wire strain gages is described. The values of longitudinal strains obtained by vibrating wire and electrical strain gage methods are compared. The geometric task of determining the deflection of the strain gage wire when it is installed in the circumferential direction on pipelines of different diameters is solved in order to assess the reliability of the strain gage readings. The main points of the methodology for evaluating the stress-strain state of main pipelines by the vibrating wire method are considered and the classification of pipeline section functional state is proposed.

DYNAMIC BEHAVIOR OF TELESCOPIC CRANES BOOM

2013 ◽  
Vol 13 (01) ◽  
pp. 1350010 ◽  
Author(s):  
IOANNIS G. RAFTOYIANNIS ◽  
GEORGE T. MICHALTSOS
Keyword(s):  
Dynamic Response ◽  
Dynamic Analysis ◽  
Dynamic Behavior ◽  
Analytical Model ◽  
Constant Velocity ◽  
Steel Beam ◽  
Continuum Approach ◽  
Theoretical Formulation ◽  
Modal Superposition ◽  
Superposition Technique

Telescopic cranes are usually steel beam systems carrying a load at the tip while comprising at least one constant and one moving part. In this work, an analytical model suitable for the dynamic analysis of telescopic cranes boom is presented. The system considered herein is composed — without losing generality — of two beams. The first one is a jut-out beam on which a variable in time force is moving with constant velocity and the second one is a cantilever with length varying in time that is subjected to its self-weight and a force at the tip also changing with time. As a result, the eigenfrequencies and modal shapes of the second beam are also varying in time. The theoretical formulation is based on a continuum approach employing the modal superposition technique. Various cases of telescopic cranes boom are studied and the analytical results obtained in this work are tabulated in the form of dynamic response diagrams.

A Ductility-Centred Analytical Model for Axially Restrained Double-span Steel Beam Systems Subjected to Sudden Columns Loss

Structures ◽  
2017 ◽  
Vol 10 ◽  
pp. 197-208 ◽  
Author(s):  
Haoran Fu ◽  
Jinfan Zhang ◽  
Jianqun Jiang ◽  
Zhenyu Wang
Keyword(s):  
Analytical Model ◽  
Steel Beam
Sign in / Sign up

Export Citation Format

Share Document