Curtain walling. Resistance to wind load. Test method

A wedged load test method is used to evaluate the adhesion strength of high-strength coatings, which have been processed with various sintering parameters. In this test, for stress concentration at cut tip, cracks are always induced and expanded rapidly cross the interface between coating and substrate. Macro-fracture and SEM image of coating interface of high-strength coating are characterized using optical microscope and scanning electron microscopy (SEM), respectively. In order to evaluate the bonding properties between coating and substrate effectively, corresponding finite element (FE) analysis has been conducted to evaluate the adhesion strength of high-strength coating. And stress distributions cross the interface of high-strength coating are obtained. The stress analysis can help to evaluate the bond strength of high-strength coating. Because of small specimen and contact relationship between wedged pressure head and wedged cuts, complex stress state is affected by many factors resulting from interface, and also by the thickness of coating.

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Multiple loading method for field testing drilled piers

Canadian Geotechnical Journal ◽

10.1139/t85-079 ◽

1985 ◽

Vol 22 (4) ◽

pp. 592-599

Author(s):

R. G. Horvath

Keyword(s):

Test Procedure ◽

Load Cell ◽

Load Test ◽

Test Method ◽

Single Test ◽

Loading Test ◽

Shaft Resistance ◽

Loading Method ◽

Multiple Loading ◽

Base Load

A multiple loading testing method is suggested, which permits testing a single drilled pier foundation under three different conditions of load support. The pier may be tested under conditions of combined shaft and end-bearing resistance, end-bearing resistance only, and shaft resistance only. The advantages of this multiple loading test method include observation of the load-transfer and displacement behaviours of the pier under these three different support conditions and verification of the values obtained for the components of load support, i.e., shaft and end-bearing resistance, all from a single test pier.A special base load cell capable of performing a different function during each cycle of loading is required. A suitable load cell, consisting of a series of Freyssi flatjacks, and the method of operation are described.A multiple loading test procedure was used successfully as part of a field investigation program on full-scale pier sockets in weak shale. Data on the load-displacement behaviour of the pier tested using the multiple loading method are reported. Information concerning piers tested using conventional single loading methods are provided for comparison.The multiple loading test results were in good agreement with results obtained from conventional testing methods. Thus the multiple loading test method provides an economical means of obtaining a large amount of design information for drilled pier foundation systems, using a single test pier. Key words: field load test, multiple loading, drilled piers and caissons, shaft resistance, end-bearing resistance, combined shaft and end-bearing resistances, base load cell, shale.

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Wind Load Simulation Test for the Vehicle Mounted Extensible Mast System

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.805-806.1794 ◽

2013 ◽

Vol 805-806 ◽

pp. 1794-1799

Author(s):

Zhao Li ◽

Chen Long Yang ◽

Yun Xu ◽

Yue Chao Chen

Keyword(s):

Control Method ◽

Wind Load ◽

Test Method ◽

Load Force ◽

Stress And Strain ◽

Thin Wall ◽

Lateral Tension ◽

Transformation Formulas ◽

Distribution Of Stress ◽

Load Simulation

Based on the Structure and wind load force characteristics of the vehicle mounted extensible mast system, a test method for the wind load simulation of the system was designed. According to the thin wall part structural feature, a method that adding lateral tension at the flanges of the mast was used to simulate wind load. Calculation method of the theoretical wind load force was given, and the transformation formulas between loading force needed and theoretical wind force was put forward, as well the control method of the test based on PID control algorithm was described. Simulation of the force condition under trapezoidal load was given by ANSYS. The results showed that using the load scheme designed, the distribution of stress and strain was almost the same as continuous load, as well as the value and position of the maximum stress and strain.

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Study on Prediction Deflection of at the Girder Midspan of Large Tonnage Gantry Crane Rigid Legs

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.628.214 ◽

2014 ◽

Vol 628 ◽

pp. 214-218

Author(s):

Da Peng Zhang ◽

Wen Ming Cheng ◽

Kun Cai

Keyword(s):

Bending Moment ◽

Moment Of Inertia ◽

Load Test ◽

Test Method ◽

Gantry Crane ◽

Deflection Curve ◽

Concentrated Load ◽

Small Load ◽

Curve Equation

It is the most important inspection index of the deflection value for the girder of gantry crane under rated load in the overall test. In the overall test for large tonnage gantry crane which prepared for experimental weight is very difficult at the site, or even impossible perform test. In the text, it is deduced the girder deflection curve equation where considering the effects of the leg bending moment to the girder deflection When the concentrated load is applied to the position of L/2,L/3 and 2L/3 of the girder. The girder deflection value can be obtained under small load at the position of L/2,L/3 and 2L/3 of the girder and the actual moment of inertia of the girder and two side leg can be obtained. In this way, the deflection of the large tonnage gantry crane are predicted through the data of the three-position method in the small load test. Three-position small load test method provides a practical and effective method for the prediction of the girder deflection of large tonnage gantry structure.

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GB-SAR in the Diagnosis of Critical City Infrastructure—A Case Study of a Load Test on the Long Tram Extradosed Bridge

Remote Sensing ◽

10.3390/rs12203361 ◽

2020 ◽

Vol 12 (20) ◽

pp. 3361

Author(s):

Przemysław Kuras ◽

Łukasz Ortyl ◽

Tomasz Owerko ◽

Marek Salamak ◽

Piotr Łaziński

Keyword(s):

Remote Sensing ◽

Cross Sections ◽

Load Test ◽

Test Method ◽

Static Load Test ◽

Remote Sensing Technique ◽

Close Range ◽

Remote Sensing Methods ◽

Contact Measurements

This article describes a case of using remote sensing during a static load test of a large bridge, which, because of its location, belongs to a critical city infrastructure. The bridge in question is the longest tram flyover in Poland. This is an extradosed-type concrete structure. It conducts a long tram line over 21 other active lines of an important railway station in the center of Cracow. The diagnostic of such bridges involving the load test method is difficult. Traditional, contact measurements of span displacements are not enough anymore. In such cases, remote sensing becomes an indispensable solution. This publication presents an example of using the close-range radar remote sensing technique of ground-based radar interferometry. However, the cross-sections of the huge bridge were observed using several methods. The aim was to confirm the conditions and efficiency of radar displacement measurements. They were therefore traditional contact measurements using mechanic sensors conducted, if possible, to the bottom of the span, for precise leveling and measurement using electronic total station. Comparing the results as well as the discussion held demonstrated the fundamental advantages of remote sensing methods over the other more traditional techniques.

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