Microsoft Word - KSR2013A291

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1 YWXZ º º t rzyywxzhy`x wƒ ƒp y t ± l Non-destructive Stress Measurement on H-shape beam in the Temporary Structure of the Railway using Magnetic Anisotropy Sensor ã ä ãã äõá ãã Seong-Won Lee *, Ji-Hyeung Yoo **, Dae-Sung Kim ** Abstract Recently, non-destructive stress measurement method using magnetic anisotropy sensor has been applied to the construction site such as steel bridges and steel pipes. In addition, steel rib used in the tunnel construction site was found to be possible to measure the stress by non-destructive method. In this study, steel loading experiments using magnetic anisotropy sensor and strain gauges were conducted to derive stress sensitivity curve for general structural rolled steel SS400 that is commonly used in civil engineering structures. As a result of laboratory experiments, stress sensitivity curves for general structural rolled steel SS400 were derived using output voltage measured by magnetic anisotropy sensor and average of stress measured by strain gauges depending on the measurement location. In addition, for the field application test of the magnetic anisotropy sensor, field experiments were conducted for the two most loaded places, H-pile and inclined struts, in the temporary structure of the railway sites. The field experiment results show a similar trend in the measured values by the magnetic anisotropy sensor and by the strain gauge, with an error of about 20MPa between the two methods, which is a sufficient resolution for engineering compared with 250MPa, the yield strength of general steels. Keywords : Magnetic anisotropy sensor, H-shape beam, Railway, Non-destructive, Stress measurement ï wƒ ƒp ± l d tzž ƒ r ¹ ƒ y ƒ m y ƒ wƒ ƒ l p s t ƒ y³ m v Ž SS400 l ƒ ˆ ep wƒ ƒ ƒ l Ž l m l ³ v Ž SS400 l ƒ g wƒ ƒ ¹ ƒ ³ ¹ y ˆƒ t ƒ q v qh l ¹ ˆ ˆˆ ¹ ˆ l m l wƒ ƒm l «r l wƒ ƒ Ÿ Ž20MPa m «v y 250MPa ye m z p Ž wƒ ƒ y t ± l Ò åñúá ÒÐ Ñæ Ñãëëêééæêéëäééäêëã ããñ á Ò øø

2 ää ï s t ƒ m Ž ¼ d n»ƒ um t o l ³ t ƒ³ p ƒ o l ³ l l ±Ž q lv o l wx l p m x r l m l xºp wx X-ƒ ± x¹º d ± l wx m v et p wx p l l o l vp l pzÿ l Ž l vr» k t k l pž k o l q y ƒ x¹º p ± l v wƒ ƒp ˆ ˆ v y t ¹ ˆ r p Özƒ wƒ ƒ y ˆƒ t ƒ zp³ ääúï äää Õ ø äääää Õ ø ò ƒ ferromagnetic substance p º magnetization ˆ«e ƒ magnetic field ƒ ek m magnetic circuit w m Ž x l xºp x¹ magnetostriction k r x¹ ºpˆ«w ³ x¹ n ek x¹ ƒ k x¹ º w m r x¹ k r x¹ º w m drz x¹ k iron steel º r x¹ vƒ l vƒ r x¹ º w m magnetic permeability Ž r l xºp wƒ ƒ º Fig. 1 Measurement principles of magnetic anisotropy sensor

3 wƒ ƒ o y ƒ ¹ 3cm 6cm r 4 ƒ l Core-D l Core-E p l p l r t xw µ x yw µ y y um l Core-E op¼pre 1 mz z z pm E 2 m p Ÿ µ x - µ y m E 1 ƒd 1, D 2 ƒe 2 mº w l Core-D o ¼l Ž vƒ äääää Õ ø Ó wƒ ƒ m{ ˆ m n m{ p 2 4 ¹ z p k ±y¹ p ˆ ª lz lz zz m l z m{ ºm zz r lz m{ ƒ Ž ³ p d l zz p3 wƒ ƒ ˆ {m p «Fig. 2 Measurement probe of magnetic anisotropy sensor MAS Probe (R-4pin) Regulator Signal Amplifier Band Pass Filter (BNC) (BNC) Function enerator (1kHz,5Vpp) Power Supply (±15V, ) Oscilloscope äää Û äääää Ï Fig. 3 Measurement system block diagram of magnetic anisotropy sensor wƒ ƒ t l ekxº ƒp l Ž m wx ekƒ l Ž l mº p l Ž l pˆ Ž y ƒ l Ž

4 l p wƒ ƒ l p p 4 ƒy v ˆ ˆ ˆ ³ vº ƒ 1 ƒy v r 0kN, 5kN, 10kN, 15kN, 20kN ƒm pˆˆ ˆ ƒ l ˆ l p r l Ž wƒ ƒm Fig. 4 Experimental schematic of Steel loading Table. 1 Specification and chemical composition of the specimen Size Type Specification (L)1,000 y (B)180 y (T)28 y SS400(Yield strength : 245MPa, Tensile strength : 425MPa, Elongation:23%) äääää ÑÑøü Chemical composition(%) C Si Mn P S Alt B (a) Strain gauge measurement results (b) Magnetic anisotropy sensor measurement results Fig. 5 Strain gauge and magnetic anisotropy sensor load step according to the measurement results ˆ l m l wƒ ƒm l

7 Stress variance-output voltage variance relationship äää äääää Ï wƒ ƒp y ˆƒ t ± l z r Ž³ ¹ ˆƒ 1 ¹ ˆ Fig.

5 Ž p p 5 ƒ y v x wƒ ƒ l ƒ l ³ (a) wƒ ƒ l Ž(b) r p6 x l l Ž ˆ ˆ p¹ p7 ƒy v l m l xºk wƒ ƒ l Ž xºk ƒ¹ p «Ž Fig. 6 Stress-Output voltage relationship(measurement locations) Fig. 7 Stress variance-output voltage variance relationship äää äääää Ï wƒ ƒp y ˆƒ t ± l z r Ž³ ¹ ˆƒ 1 ¹ ˆ Fig. 8 Measurement probe of magnetic anisotropy sensor ¹ ˆƒ x H-Pile+ ox r, H-Pile ˆ ˆ SS400 ˆ ¹º ƒƒˆž2m Ÿ r ƒƒ» mž2m Ÿ ¹ ˆ p 8 ƒy v ¹ ˆƒ t ƒ q v qh l 2 l wƒ ƒp ¹ ˆˆ

6 äääää ÑÑ wƒ ƒp y ˆƒ t ¹ ˆ p10 ƒy v l wƒ ƒ «r l wƒ ƒ Ÿ Ž20MPa Ž (a) Inclined struts measurement results (b) H-Pile measurement results Fig. 10 Strain gauge and magnetic anisotropy sensor measurement results comparison ääñï y ƒ ¹ y ˆƒ t ± l wƒ ƒ ƒ ˆ ƒ wƒ ƒ l p s t y³ m SS400 ˆ ˆ ˆ o l l ŽŽ e Ž z ƒ wƒ ƒ l Ž m ekxº l Ž xºk l lxºk ƒ¹ p «Ž p ˆ ˆ p m¹ ˆ ¹ ˆ y ˆƒ t ƒ q v qh l wƒ ƒ l p l ˆxºp ¹ l wƒ ƒ «r l wƒ ƒ Ÿ Ž20MPa m «r v y 250MPa ye m z p Ž Ñö [1] ƒ, ¹, t¹d (2011) wƒ ƒp ± ± l, vº º t, 12(11), pp [2] S. Akutagawa, K. Matsuoka, H. Sekimoto, T. Kobayashi, T. Uda, M. Ota and K. Yasuhara (2003) Use of Magnetic Anisotropy Sensor for Nondestructive Stress Measurement of H-beams used in Tunnel Support Systems, Proceedings of the 39 th US Rock Mechanics Symposium, MIT, pp

Microsoft Word - KSR2012A172.doc

Microsoft Word - KSR2012A172.doc YWXY º º t rzyywxyhx^y v s k v A Study on the Development of Traction Jig for Bimodal Tram ã äø Ñ ã ä ãã Hee-Taek Yoon *, Young-Kon Park *, Se-Hyun Cho ** ) Abstract The bimodal tram ahead of practical