Service life of GGBFS concrete under carbonation through probabilistic method considering cold joint and tensile stress

2020 ◽  
Vol 32 ◽  
pp. 101826
Author(s):  
Yong-Sik Yoon ◽  
Keun-Hyeok Yang ◽  
Seung-Jun Kwon
Keyword(s):  
Service Life ◽  
Tensile Stress ◽  
Probabilistic Method

Analysis of Performance Decay Behavior for Asphalt Pavement Based on Aging

2013 ◽  
Vol 723 ◽  
pp. 22-26 ◽  
Author(s):  
Pei Long Li ◽  
Zhan Ding ◽  
Zheng Qi Zhang
Keyword(s):  
Shear Stress ◽  
Service Life ◽  
Tensile Stress ◽  
Simulation Analysis ◽  
Asphalt Pavement ◽  
Maximum Shear Stress ◽  
Maximum Tensile Stress ◽  
Pavement Structure ◽  
Analysis Of Performance ◽  
Decay Behavior

Aging is a main factor affecting the durability of asphalt pavement. To study decay behavior of asphalt pavement with aging, aged asphalt was extracted from stratified pavement mixtures for different service-life. The changes of asphalt properties with service time and depth variations of the pavement were discussed. And numerical simulation analysis of pavement structure was conducted with pavement gradient modulus changes caused by aging. The results indicate that asphalt stiffness increases and low-temperature performance decays sharply with the extension of pavement service life, especially in the first several years. The vertical aging differences from top to bottom of pavement were significant, the aging extents decrease continuously from the surface, which cause the gradient changes of pavement modulus. The maximum tensile stress and maximum shear stress all increase with surface modulus increasing, so more serious aging can induce greater gradient modulus, shear stress and tensile stress are larger under the same loads, which have more serious damage to the pavement structure.

scholarly journals Service Life Evaluation for RC Sewer Structure Repaired with Bacteria Mixed Coating: Through Probabilistic and Deterministic Method

Materials ◽  
2021 ◽  
Vol 14 (18) ◽  
pp. 5424
Author(s):  
Hyun-Sub Yoon ◽  
Keun-Hyeok Yang ◽  
Kwang-Myong Lee ◽  
Seung-Jun Kwon
Keyword(s):  
Surface Roughness ◽  
Service Life ◽  
Coating Thickness ◽  
Probabilistic Method ◽  
Probabilistic Methods ◽  
Ion Concentration ◽  
Design Parameters ◽  
Deterministic Method ◽  
Repair Mortar ◽  
Life Evaluation

Since a concrete structure exposed to a sulfate environment is subject to surface ion ingress that yields cracking due to concrete swelling, its service life evaluation with an engineering modeling is very important. In this paper, cementitious repair materials containing bacteria, Rhodobacter capsulatus, and porous spores for immobilization were developed, and the service life of RC (Reinforced Concrete) structures with a developed bacteria-coating was evaluated through deterministic and probabilistic methods. Design parameters such protective coating thickness, diffusion coefficient, surface roughness, and exterior sulfate ion concentration were considered, and the service life was evaluated with the changing mean and coefficient of variation (COV) of each factor. From service life evaluation, more conservative results were evaluated with the probabilistic method than the deterministic method, and as a result of the analysis, coating thickness and surface roughness were derived as key design parameters for ensuring service life. In an environment exposed to an exterior sulfate concentration of 200 ppm, using the deterministic method, the service life was 17.3 years without repair, 19.7 years with normal repair mortar, and 29.6 years with the application of bacteria-coating. Additionally, when the probabilistic method is applied in the same environment, the service life was changed to 9.2–16.0 years, 10.5–18.2 years, and 15.4–27.4 years, respectively, depending on the variation of design parameters. The developed bacteria-coating technique showed a 1.47–1.50 times higher service life than the application of normal repair mortar, and the effect was much improved when it had a low COV of around 0.1.

Probabilistic Method for Service Life Estimation of Reinforced Concrete Roof Trusses of Operated Industrial Building

2016 ◽  
Vol 7 (6) ◽  
pp. 158
Author(s):  
V. A. Pshenichkina ◽  
Kseniya N. Sukhina ◽  
V. V. Drozdov ◽  
V. A. Babalich ◽  
K. A. Sukhin ◽  
...  
Keyword(s):  
Reinforced Concrete ◽  
Service Life ◽  
Probabilistic Method ◽  
Industrial Building ◽  
Life Estimation ◽  
Service Life Estimation

Effect of Asphalt Layer Modulus on the Mechanical Properties and Service Life of Heavy Load Semi-Rigid Asphalt Pavement

2011 ◽  
Vol 368-373 ◽  
pp. 193-196
Author(s):  
Xiao Hua Wang ◽  
Ji Shu Sun ◽  
Tian Xiao ◽  
Hui Ran Pi
Keyword(s):  
Mechanical Properties ◽  
Service Life ◽  
Tensile Stress ◽  
Asphalt Pavement ◽  
Pavement Design ◽  
Heavy Load ◽  
Surface Deflection ◽  
Pavement Structure ◽  
Base Course ◽  
Design Result

Asphalt layer modulus is one of the important mechanical parameters in pavement design. It will directly influence the design result and the mechanical properties of asphalt pavement structure. Using pavement design and analysis software, the effects of asphalt layer modulus on surface deflection, tensile stress at the bottom of base and sub-base course, stress at the the bottom of asphalt layer and service life of heavy load semi-rigid asphalt pavement structure were analyzed systematically. And the influencing laws were analyzed, too. The results indicate that the mechanical properties, deforming characteristics and service life of heavy load asphalt pavement were influnced significantly by asphalt layer modulus. With the increasing of asphalt layer modulus, the surface deflection, tensile stress at the bottom of base and sub-base course would significantly decrease, and service life of heavy load semi-rigid asphalt pavement structure would be improved.

scholarly journals Total Repair Cost Simulation Considering Multiple Probabilistic Measures and Service Life

2021 ◽  
Vol 13 (4) ◽  
pp. 2350
Author(s):  
Yong-Sik Yoon ◽  
Yong-Han Ahn ◽  
Xiao-Yong Wang ◽  
Seung-Jun Kwon
Keyword(s):  
Service Life ◽  
Probabilistic Method ◽  
Repair Process ◽  
Maintenance Cost ◽  
Repair Cost ◽  
Repair Strategy ◽  
Repair Materials ◽  
Probabilistic Measures ◽  
Extended Service

In this study, the total maintenance cost for public houses in South Korea was analyzed, and the effect of each repair process on the total maintenance cost was evaluated with probabilistic and deterministic methods. In the probabilistic method, quality of repair materials and construction skills were considered in the variability of extended service life through repair, while the deterministic method considered it by simple summation of repair step. The repair cost was analyzed considering the coefficient of variation (COV) of extended service life, so the reasonable total maintenance cost was able to be evaluated. Since the results through the probabilistic method provided a continuous cost line, a reasonable repair strategy was carried out by simply changing the intended service life of the structure. The repair cost was additionally analyzed with constant COV (0.15) of each repair process for considering various situations. The analysis results with a COV of 0.15 exhibited a slightly higher maintenance cost than those with current COV. The total maintenance costs can be adjusted if the initial repair timing is extended to the largest possible extent for the highest-repair-cost process since the total repair cost is dominated by the process with the highest repair cost.

Change of Steel’s Yield Stress Over Ship’s Service Life and its Effect on the First Yield Hull Girder Bending Moment - Technical Note

2013 ◽  
Vol 155 (A3) ◽  
Keyword(s):  
Service Life ◽  
Tensile Stress ◽  
Laboratory Test ◽  
Yield Stress ◽  
Bending Moment ◽  
Probability Of Failure ◽  
Technical Note ◽  
Bulk Carrier ◽  
Shipbuilding Steel ◽  
Hull Girder

The publication deals with the decrease of the yield and tensile stress of high tensile shipbuilding steel AH-32 over ship's service life and its effect on the first yield bending moment as a representative of the hull girder capacity. An example is given for a sample 25K DWT (25 thousand tons deadweight) bulk carrier. The probability of failure is calculated as the probability of the total hull girder bending moment exceeding the first yield bending moment. The probabilistic distributions of yield and tensile stress are obtained from laboratory test of the specimen of AH-32 steel (corroded plates of a 20 year old ship). It is found that although the decrease of yield stress may not be great, the increase of the probability of failure (i.e., the probability that the total hull girder bending moment will exceed the first yield bending moment) could be substantial.

Study on Mechanism of Tap Breakage in Low Frequency Torsional Vibration Tapping

2010 ◽  
Vol 37-38 ◽  
pp. 1306-1310
Author(s):  
Feng Qi Han ◽  
Zhi Zun Li ◽  
De Yuan Zhang
Keyword(s):  
Stress State ◽  
Service Life ◽  
Tensile Stress ◽  
Failure Mode ◽  
Torsional Vibration ◽  
Impact Load ◽  
Low Frequency ◽  
Rake Angle ◽  
Shock Resistance ◽  
Large Tensile Stress

Early breakage of tap often occurs when tapping on difficult-to-cut materials with the method of low frequency torsional vibration tapping, which decreases the technological effect and restricts its application. The effect of impact load on tap breakage in vibration tapping was analyzed, and the stress state in tap teeth was simulated by FEM, on this basis, it is concluded that too large tensile stress in tap teeth is the main cause of early breakage of tap. To reduce the tensile stress and enhance the shock resistance of tap teeth, the tap should be ground to minor negative rake angle. Experiments showed that the failure mode of grinded taps changed to wear, and thereby the service life of tap was prolonged significantly.

Sign in / Sign up

Export Citation Format

Share Document