• International Journal of Safety
• /
• v.9 no.2
• /
• pp.16-21
• /
• 2010

In this study, the variations of transformed impact factors and load carrying capacity of highway bridges measured from the state of expansion joint are evaluated. the field loading tests were performed on the highway bridge with damaged expansion joint to investigate the variation of the load carrying capacity. From the field loading tests in case that damaged expansion joint exist or do not exist, the static displacements and dynamic displacements were measured, and TIF were calculated, respectively. dynamic test is performed in order to estimate dynamic displacement and TIF according to the level of damage of expansion joint. From the results of TIF, the load carrying capacity of highway bridges with damaged expansion joint were estimated.

• Journal of the Korea Safety Management & Science
• /
• v.25 no.2
• /
• pp.187-192
• /
• 2023

In piping systems, trapeze hangers are subjected to vertical and horizontal seismic loads and stiffeners are used. In this study, monotonic compression tests were conducted with the removable stiffeners using three variables: stiffener clamp fixing position, section length, and installation direction. The maximum load reinforced with stiffeners could withstand a compressive load of 11kN by applying a safety factor of 10%. It could be estimated that the fixing clamp spacing or the length of shape and load had a proportional relationship. And the stiffener must be fixed in the direction of the strong axis on hinge parts. Also the stiffener buckiling load design proposes to use a method of calculate the flexural buckling compressive strength of and unreinforced full threaded bolt.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 1997.11a
• /
• pp.472-476
• /
• 1997

Hot-smoke testing in Australia has progressed to the stage where there is an Australian Standard for these tests. The purpose of such tests is twofold: firstly they can validate computer modeling predictions for smoke movement, and secondly they can demonstrate that the smoke control systems and associated fire safety systems function satisfactorily. Hot-smoke tests were carried out in March 1997 at two of Sydney's underground railway stations, namely St James and Museum. The purpose of the tests was to demonstrate that the smoke control systems performed their functions as intended. Tests were carried out in the concourses and on the platforms, and trains ran during the tests so that the effect of moving trains on smoke movement could be observed. A total of five tests were carried out and video recordings were taken of each. This is the first time that hot-smoke tests have been carried out in an underground station with trains running. The paper discusses some of the interesting observations and the problems identified by the tests.

• Journal of Biosystems Engineering
• /
• v.41 no.3
• /
• pp.153-160
• /
• 2016

Purpose: This study was conducted to experimentally investigate the structural safety of and identify critical locations in a front-end loader under impact loads. Methods: Impact and static tests were conducted on a commonly used front-end loader mounted on a tractor. In the impact test, the bucket of the front-end loader with maximum live load was raised to its maximum lift height and was allowed to free fall to a height of 500 mm above the ground where it was stopped abruptly. For the static test, the bucket with maximum live load was raised and held at the maximum lift height, median height, and a height of 500 mm from the ground. Strain gages were attached at twenty-three main locations on the front-end loader, and the maximum stresses and strains were measured during respective impact and static tests. Results: Stresses and strains at the same location on the loader were higher in the impact test than in the static test, for most of measurement locations. This indicated that the front-end loader was put under a severe environment during impact loading. The safety factors for stresses were higher than 1.0 at all locations during impact and static tests. Conclusions: Since the lowest safety factor was higher than 1.0, the front-end loader was considered as structurally safe under impact loads. However, caution must be exercised at the locations having relatively low safety factors because failure may occur at these locations under high impact loads. These important design locations were identified to be the bucket link elements and the connection elements between the tractor frame and front-end loader. A robust design is required for these elements because of their high failure probability caused by excessive impact stress.

• Journal of Radiation Protection and Research
• /
• v.26 no.1
• /
• pp.35-43
• /
• 2001

All of sealing capsules to transport a special form radioactive material should be designed and fabricated in accordance with the design criteria prescribed in IAEA standards and domestic regulations. The objective of this study is to demonstrate the safety of a shipping capsule for $^{192}Ir$ special form radioisotope which produced in the HANARO. The safety tests were carried out for the impact, percussion, bending and heat test conditions. And leakage tests were carried out before and after the each test. Also, the safety analyses wert performed using computer codes in order to verify the test results. The capsule showed slight scratches and deformation, and maintained its structural and thermal integrities in all tests without any severe damage or melting. It also met the allowable limits of leakage rate after each test. Therefore, it has been verified that the capsule was designed and fabricated to meet all requirements for the special form.

• Proceedings of the KSR Conference
• /
• 2000.11a
• /
• pp.557-570
• /
• 2000

It is necessary to perform a study on the interrace between a G7 pantograph and a KTX catenary system prior to G7 on-line tests in the Korea High Speed Test Track in order to predict how high current collection quality can be obtained during the on-line tests and check if safety problems shall be caused b)Y the tests or not. According to the simulation results, current collection quality of the G7 pantograph at 350km/h is lower than that of a GPU pantograph at 300km/h, but the contact wire uplifts and average contact forces are within the safe-zone. In addition, the ratio of running speed (350km/h) to safe running. Therefore, the G7 on-line tests at 350km/h in the Korea High Speed Test Track is expected not to cause the safety problem.

• Geomechanics and Engineering
• /
• v.13 no.4
• /
• pp.621-640
• /
• 2017

The double-row long-short composite anti-sliding piles system is an effective way to control the landslides with high thrust. In this study, The double-row long-short composite anti-sliding piles with different load segment length (cantilever length) and different pile row spacing were studied by a series of physical tests, by which the influences of load segment length of rear-row piles as well as pile row spacing on the mechanical response of double-row long-short composite anti-sliding pile system were investigated. Based on the earth pressures in front of and behind the piles obtained during tests, then the maximum bending moments of the fore-row and the rear-row piles were calculated. By ensuring a equal maximum moments in the fore-row and the rear-row piles, the optimum lengths of the rear-row piles of double-row long-short composite system under different piles spacing were proposed. To investigate the validity of the reduced scale tests, the full-scale numerical models of the landside were finally conducted. By the comparisons between the numerical and the physical test results, it could be seen that the reduced scale tests conducted in this study are reliable. The results showed that the double-row long-short composite anti-sliding piles system is effective in the distribution of the landslide thrust to the rear-row and the fore-row piles.

• Nuclear Engineering and Technology
• /
• v.48 no.5
• /
• pp.1083-1095
• /
• 2016

The design of Prototype Gen-IV Sodium-Cooled Fast Reactor (PGSFR) has been developed and the validation and verification (V&V) activities to demonstrate the system performance and safety are in progress. In this paper, the current status of test activities is described briefly and significant results are discussed. The large-scale sodium thermal-hydraulic test program, Sodium Test Loop for Safety Simulation and Assessment-1 (STELLA-1), produced satisfactory results, which were used for the computer codes V&V, and the performance test results of the model pump in sodiumshowed good agreement with those in water. The second phase of the STELLA program with the integral effect tests facility, STELLA-2, is in the detailed design stage of the design process. The sodium thermal-hydraulic experiment loop for finned-tube sodium-to-air heat exchanger performance test, the intermediate heat exchanger test facility, and the test facility for the reactor flow distribution are underway. Flow characteristics test in subchannels of a wire-wrapped rod bundle has been carried out for safety analysis in the core and the dynamic characteristic test of upper internal structure has been performed for the seismic analysis model for the PGSFR. The performance tests for control rod assemblies (CRAs) have been conducted for control rod drive mechanism driving parts and drop tests of the CRA under scram condition were performed. Finally, three types of inspection sensors under development for the safe operation of the PGSFR were explained with significant results.

• Bulletin of the Korean Chemical Society
• /
• v.23 no.1
• /
• pp.75-80
• /
• 2002

Cycle life tests have been carried out to evaluate the influence of safety valve pressure on valve regulated lead/acid batteries under deep cycling applications. Batteries were cycled at 5 hour rates at 100% DOD, and safety valve pressure was set to 1.08 and 2.00 bar, respectively. The batteries lost 248.3 g and 235.3 g of water for each case after about 1,200 cycles, but the cyclic performances of the batteries were comparable. Most of the gas of the battery during discharging was hydrogen, and the oxygen concentration increased to 18% after 3 hours of charging. The micro structure of the positive active materials was completely changed and the corrosion layer of the positive grid was less than $50{\mu}m$, regardless of the pressure of the safety valve after cycle life tests. The cause of discharge capacity decrease was found to be water loss and the shedding of the positive active materials. The pressure of safety valve does not give little effect to the cyclic performances and the failure modes of the gelled electrolyte valve-regulated lead acid batteries.

• Journal of the Korean Society of Safety
• /
• v.30 no.2
• /
• pp.1-8
• /
• 2015

Forklift truck is a very convenient transportation vehicle and widely used in industries. However, a lot of overturn accidents occur during operation because of poor understanding on the stability of forklift trucks. The stability of a forklift is defined by the minimum slope of the ramp where a forklift truck overturns. According to the KS BISO 22915-2 code, the stability is determined from the four kinds of stability tests. The equations for the stability of a forklift truck were proposed already in several published literatures and the equations can be used conveniently to estimate the stability and examine the effects of design parameters in forklift trucks. However, because the detail derivation procedure was omitted, it is very difficult to examine the accuracy of the proposed equations and to modify the equations for other types of forklift trucks. In this paper the stability equations were derived again with detail derivations for the four kinds of stability tests. And the effects of acceleration or centrifugal forces were also additionally included in the equations and minor corrections were also made.