Accelerated alkali resistance test were conducted for pre-heated GFRP Rebar. The GFRP rebar specimens were heated to temperatures of 60℃, 120℃, 200℃ and 300℃ and then immerged in alkali solution for 30days. According to ACI 440.3R-12, tensile properties were measured.
In this paper, we investigate the pozzolanic reaction of the waste glass sludge incorporating precipitation additives experimentally. The consumption of calcium hydroxide, and the compressive strength were tested for two different types of the waste glass sludge depending on whether precipitation additives were used.
In this paper, the heavy metal leaching of mortar substituted the crushed waste glass as fine aggregate are evaluated. From the results, when the heavy weight waste glass substitution ratio increase, leching quantities of heavy metal is increased. Therefore, it is needed that the characteristics of heavy metal leching according to waste glass substitution ratio in mortar specimens.
In this research we carried out the compressive strength, modulus of rupture and scaling resistance tests in order to evaluate the durability of concrete pavement containing waste glass powder. As a results of this research, the concretes incorporating 20% waste glass powder had higher compressive strengths and modulus of ruptures than the concretes with 20% fly-ash. Also, they had a better scaling resistance than ordinary portland cement concretes and fly ash concretes.
An experiment was conducted to recycle sulfur which is industrial by-product, by producing concrete mix materials. production of specimens were implemented on the replacement of modified sulfur emulsion with cement. this paper presents data on the experimental results of durability test of the each specimens.
In this study, Corrosion behavior in mortar was observed by the passage of time by using EIS method. As a result of EIS experiment, equivalent circuit and changes of Impedance parameter could be observed. In addition, it was confirmed that impedance of rebar in mortar and corrosion rate according to the amount of NaCl were different.
Recently, Advanced water treatment facilities with Ozone are being introduced domestically. However, waterproofing/corrosion prevention construction method of concrete structure for existing advanced water treatment makes waterproofing/corrosion prevention materials and concrete deteriorated because of strong oxidation of ozone. Therefore, in this study, As a one of studies for improving durability of advanced water treatment plant applied by metal spray system, electrochemical corrosion protection of metal spraying film according to surface treatment in pH 5 acid solution which is similar to pH concentration in real ozone treatment was evaluated..
The combined effect of carbonation and chloride ingress in concrete is studied in this paper. A coupled simulation of the transports of carbon dioxide, chloride ions, heat and moisture is carried out. Several sets of experimental data were compared with the prediction by the numerical model developed in this paper, for its verification.
Chloride ions ingress continuously in reinforced concrete through pores of it by Cl-. Recently, new materials removing harmful anions have been developed. Layered double hydroxides(LDH) has an excellent ability to remove harmful anions because various anions can be adsorbed in the interlayer space between divalent and trivalent cations. In this study, Ca/Al-NO3 and Mg/Al-NO3 LDH were prepared by using a co-precipitation method. Experiments for binding chloride ions of LDH were conducted by using potentiometric method.
This study is corroborated as a fundamental resource to develop lightweight foamed concrete. Weight of unit volume decreased until 0.8% dosage of foaming agent is put cement paste. After that, Mechanical properties of cement paste with foaming agent is verified to use FEM analysis based on picture image. Finally, It is compared with compressive strength of experiment and estimation from picture image.
When substation structures are designed, it is important to investigate the design, construction and maintenance plans to enhance the endurance for chloride environment, freezing and electrochemical attack. The research is conducted to investigate intended service life of reinforced concrete substation structures.
In This Study, it was intended to performance of the joint grout for offshore wind power substructure. The flow, setting time, compressive strength, flexural strength, tensile strength of basic property and resistance to rapid freezing and thawing, ability to resist chloride ion penetration were carried out as the performance test. Also, on the grout by adding fiber checked flexural toughness, cracking tendency test.
The purpose of this study was to investigate deformation and reduction of initial clamping force in slip critical type connection under fatigue loading. And, the parameters of this study were the different clamping force and friction coefficient of surface of plate. As a result, the clamping force of all specimens were generally decreased in comparison with initial values under fatigue loading.
The aim of the research is suggesting the curing method and selection of surface-covered curing materials with the goal of achieving non-cracking concrete by applying on the actually constructed top slab of the apartment and comparing the surface covering method using single-layered white bubble sheet with the surface covering method using polyethylene film.
This study is subway tunnel field application about repair materials with crack self-healing capability. It was found that it showed good durability compared to the existing repair materials through lab test. Utilization of these mortars may have high potential for a new repair material.
This study investigated the tensile property of high performance concrete according to addition of plastic bead. Test results showed that the addition of PS beads induced the decrease of crack width and increase of number of cracks while maintaining tensile strength and tensile strain capacity.
In reinforced concrete (RC) structures, concrete carbonation depth is an important criterion for the deterioration of durability of RC structures. Concrete carbonation is influenced by multiple factors such as chloride attack, crack, concrete compressive strength, etc. However, due to its complex mechanism, most previous studies considered only one or two deterioration factors to estimate the concrete carbonation depth. In this study, therefore, inspection data were collected from 8 buildings, and the Adaptive Neuro-Fuzzy Inference System (ANFIS) algorithm that estimates the concrete carbonation depth of RC structures has been proposed. The proposed ANFIS model provided good estimations on the carbonation depths.
This paper showed evaluations of mechanical performances of High-Performance Fiber Composite Mortar which made by cement free binders with Alkali-activated slag and PVA fibers with the volume fraction of 1~1.5%. Specimens were subjected to compressive, tensile and shear strength test and the test results showed their high performance mechanical characteristics.
This study evaluates tensile strength and percentage extension of the four kinds reinforcement type for the development of continuous pavement technology road joints using geosynthetic reinforcement was to choose the best geosynthetic reinforcement to satisfied the target reference value.
This study examines the strength properties use of talc as a substitute for OPC-GGBFS cement. The test was carried out by replacing the plain mix(OPC : GGBFS = 50 : 50) with talc at the rate of 0~100%. The OPC contents was constant in all mixtures. The mixtures replaced GGBFS with talc. The results showed that the compressive strength and bending strength decreases with an increase in talc contents.