scholarly journals Thermal loading test of a Wendelstein 7-X pumping gap panel

2022 ◽  
Vol 175 ◽  
pp. 112986
Author(s):  
J. Boscary ◽  
F. Schauer ◽  
B.-E. Ghidersa ◽  
R. Krüßmann ◽  
M. Lux ◽  
...  
Keyword(s):  
2020 ◽  
Vol 10 (2) ◽  
pp. 461 ◽  
Author(s):  
Lingyu Zhou ◽  
Tianyu Wei ◽  
Guangchao Zhang ◽  
Yingying Zhang ◽  
Mahunon Akim Djibril Gildas ◽  
...  

To study the initiation and expansion of the interlayer gap of the China Railway Track System Type II (CRTS-II) ballastless slab track structure under the action of repeated thermal loading as well as the influence of the interlayer gap on the displacement, strain and stiffness of the track structure, a 1/4 scale three-span ballastless slab track simply supported bridge structural system specimen was developed and 18 cycles of extremely thermal loading tests were carried out. Static loading tests were carried out before and after the repeated thermal loading test and the effects of the repeated temperature loading on the mechanical properties of the structural system were analyzed. The test results show that under repeated temperature loading, there is a gap between the track slab and cement emulsified asphalt (CA) mortar near the fixed end section of the beam (close to the shear slots). The interlayer gap gradually expands to the mid-span section in a “stepped” shape in three stages: initiation, expansion and stabilization. Under the same temperature load, the camber of the concrete box beam decreases gradually while that of the track structure increases gradually with the increase of the interlayer gap length. During the three stages of interlayer gap development, the track structure stiffness degrades gradually, and the fastest reduction rate during the expansion stage. At the end of the 18th cycle of thermal loading, a degradation of 14.96% and 2.52% is observed in the stiffness of the track structure and that of the ballastless track-bridge structural system, respectively.


2015 ◽  
Vol 52 (9) ◽  
pp. 091408
Author(s):  
聂树真 Nie Shuzhen ◽  
孙辉 Sun Hui ◽  
虞钢 Yu Gang ◽  
樊仲维 Fan Zhongwei

1993 ◽  
Vol 28 (4) ◽  
pp. 263-272 ◽  
Author(s):  
F P E Dunne ◽  
D B Puttergill ◽  
D R Hayhurst ◽  
Q J Mabbutt

A thermal shock test facility is designed and built to enable to enable a copper model slag tap component to be tested under cyclic thermal loading conditions. Infra-red line heaters and pumped cooling water are used to impose temperature loading cycles on to the specimen. Accurate focussing of the line heaters using a two degree of freedom adjustment mechanism, enables a heating area of width 3 mm to be applied to the specimen. Both the heating and the cooling processes are controlled by a proportional, integral, and derivative feedback micro-processor controller. Specimen temperature fields are obtained using thermocouples, and specimen displacements and strains are measured using linear voltage displacement transducers and strain gauges. A cyclic thermal loading test is carried out for approximately 7150 cycles on a model slag tap component. The variations of specimen strains and displacements are recorded and compared with results obtained from a finite element viscoplastic damage analysis. Good agreement between the predicted and experimental results is obtained. Microstructural examination of the specimen reveals the development of persistent slip bands and micro-cracking at grain boundaries. This occurs at the regions of the specimen undergoing cyclic plasticity due to the imposed cyclic thermal loading. The experimental observations of cyclic plasticity damage formation in copper undergoing cyclic thermal loading indicates the suitability of the Continuum Damage Mechanics (CDM) theory to model the evolution of cyclic plasticity damage. The damage is characterized by the development of fields of micro-cracked grain boundaries due to the formation and interaction of persistent slip bands within the grains.


1978 ◽  
Vol 87 (1) ◽  
pp. 181-191 ◽  
Author(s):  
Alfred S. Wolf ◽  
Klaus A. Musch ◽  
Werner Speidel ◽  
Jürgen R. Strecker ◽  
Christian Lauritzen

ABSTRACT A new model for the perfusion of human term-placentas has been developed for studies on the placental biogenesis of C-18 and C-19 steroids. For viability criteria, the glucose- and oxygen-consumption, regional perfusion control by dye-infusions or scanning after injection of 99Tc-labelled macroparticles, and the histological qualification were chosen. The recycled perfusate was investigated for the steroids oestrone (Oe1), oestradiol-17β (Oe2), oestriol (Oe3), 4-androstene-3,17-dione (A), testosterone (T), and human placental lactogen (HPL) by radioimmunoassay in controls and perfusions with the foetal steroid precursor dehydroepiandrosterone sulphate (DHA-S). In control perfusions, steroid hormones were found in constant ratios (Oe1:Oe2:Oe3:T:A = 30:1.5:100:0.35:1). Following the administration of 10 mg DHA-S for testing the metabolic capacity of the organ, high concentrations of Oe1 (90–720 ng/ml = 250–3970 % as compared to 100% pre-injection values) were found, shortly preceded by a rapid increase of A (66–1000 ng/ml = 100–16 000 %). A typical surge of T (5.3–147 ng/ml = 265–4640 %) preceded the normally slower increment of Oe2 (22–220 ng/ml = 1570–4330 %). The concentrations of Oe3 and HPL remained nearly unchanged. From different steroid patterns after DHA-S-load, two distinct responses of term-placentas could be differentiated: Group I (n=12) showed high concentrations of Oe1 (3200 ± 940 %), a small increase of T (1020 ± 500%), as well as low and delayed values of Oe2 (1660 ± 450%). In Group II (n = 5), values were high for T (3160 ± 1020%) and Oe2 (3300 ± 1110%), whereas Oe1 was found in a lower range (508 ± 302%). In contrast to in vivo findings in maternal venous blood after DHS-S injection to the mother, oestrone was found in perfusions as the main oestrogen fraction from DHA-S. Thus, the analysis of such metabolic differences might be of help in the interpretation of complex results from the DHA-S-loading test.


1959 ◽  
Vol XXXII (I) ◽  
pp. 23-32 ◽  
Author(s):  
Kurt Schubert ◽  
Hans Schröder

ABSTRACT A testosterone test using two different dosages was carried out simultaneously in 7 women suffering from metastasizing carcinoma of the mamma and in 3 normal women. In each case the urinary steroids were estimated before the beginning of the test and after administration of 50 mg and 100 mg of testosterone respectively; the interval between the single estimations being one week. The use of fractionated hydrolysis enabled a mild fission of the conjugates and the classification of the products into free steroids, glucuronosides, sulfates and unknown conjugates. The 17-ketosteroids and the testosterone were estimated by means of Girard's separation and adsorption chromatography. During the loading test with testosterone different behaviours became evident, which had not been realized before. The behaviour of the 17-ketosteroids rendered possible the differentiation of normal women from patients with cancer of the breast yet without hepatic insufficiency, and furthermore of these latter ones from those with a liver damage in addition to the cancer of the breast. The glucuronosides of the 17-ketosteroids are only depressed, when there exists a pronounced damage of the liver; the loading test making possible an extension of the range of recognizable damages. Furthermore, the behaviour of dehydroepiandrosterone (II/III), of androsterone (IV), and of aetiocholanolone (V) lends itself to this differentiation. In advanced cancer of the breast the values of II/III are invariably low, whilst IV and V often increase temporarily. The relation of IV to V may be altered in a different way. The excretion of not transformed testosterone is less in patients than in normal women and especially low in patients with liver damage.


2019 ◽  
Vol 7 (1) ◽  
pp. 30-34
Author(s):  
A. Ajwad ◽  
U. Ilyas ◽  
N. Khadim ◽  
Abdullah ◽  
M.U. Rashid ◽  
...  

Carbon fiber reinforced polymer (CFRP) strips are widely used all over the globe as a repair and strengthening material for concrete elements. This paper looks at comparison of numerous methods to rehabilitate concrete beams with the use of CFRP sheet strips. This research work consists of 4 under-reinforced, properly cured RCC beams under two point loading test. One beam was loaded till failure, which was considered the control beam for comparison. Other 3 beams were load till the appearance of initial crack, which normally occurred at third-quarters of failure load and then repaired with different ratios and design of CFRP sheet strips. Afterwards, the repaired beams were loaded again till failure and the results were compared with control beam. Deflections and ultimate load were noted for all concrete beams. It was found out the use of CFRP sheet strips did increase the maximum load bearing capacity of cracked beams, although their behavior was more brittle as compared with control beam.


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