Papers by Keyword: Self-Compacting Concrete (SCC)

Abstract: Drying creep of self-compacting concrete (SCC) has two different sources: microcracking and stress-induced shrinkage. Based on theory for pore water and microcracking theory of concrete, the model for drying creep caused by constant stress is derived from rheological equations. The proposed model is coupled with FEM analysis by recursive calculation, so that the creep caused by changing load can be calculated without considering stress history. Verification of the model is conducted through comparison with experimental result and Bazant’s empirical model. The comparing results validate the model for drying creep of SCC.

Abstract: The self-compacting concrete is playing more and more important role in the construction industry with the advantages of greater mobility, better stability, and excellent character of filling the gap through capacity. There are different raw materials and construction conditions in each region, so, the research and development of the self-compacting concrete has a special significance according to the specific circumstances of each region. In this study, the parameters of the volume of coarse aggregate, mortar volume, the volume fraction of the sand, the mineral admixtures ash and cementatious coefficient were selected and calculated, and the C40 self-compacting green concrete was successfully configured.

Abstract: It is studied the effect of binder quantity, water binder ratio on properties of self-compacting concrete made with recycled coarse aggregates. It can be prepared C50 self-compacting concrete made with recycled coarse aggregate by adjusting send proportion, binder quantity, and mixing mineral additive. For example, when the binder quantity is 600 kg/m3, water binder ratio is 0.28, the flexural strength and compressive strength at 28 days of self-compacting concrete made with recycled coarse aggregates are 9.07 MPa and 68.47 MPa respectively.

Abstract: In this paper,the functions and performances of filling layer of self-compacting concrete(SCC) in CRTS(China Railway Track System)-Ⅲ type track system were introduced. Developments of SCC including design methods and test method was described in detail. The influencing factors of workability of SCC was analysised. The trends of future development of mix proportion design methods,durability evaluation admixtures,applications were discussed.This paper also pointed that it's importance for SCC to studying the quality control methods and the application.

Abstract: In this paper, the fresh properties of self-compacting concrete (SCC) using recycled coarse aggregate (RCA) were evaluated. Five types of SCC mixtures were made, where the percentage of substitution of natural coarse aggregate by RCA was 0, 25, 50, 75 and 100%. The cement content, water to binder (W/B) ratio and Superplasticizer dosage were kept the same for all mixes. The effects of RCA on the key fresh properties such as filling ability, passing ability, and segregation resistance of SCC were investigated by conducting several fresh concrete tests included slump-flow, L-box, and sieve stability tests. The overall test results suggest that RCA can be used to produce SCC substituting up to 100% natural coarse aggregates without affecting the key fresh properties of concrete.

Abstract: A study of a mechanical performance(Compressive strength, flexural strength, and splitting tensile strength)of self-compacting (SCC) and conventional (NCC)concretemixes and some physical properties of the mixes made of Portland cement under the effect of acidic solution attackare made. Trichloroacetic and Salicycilic acids are selected and used in this study. It is found that the reduction percentage in compressive strength is about 6% and 3% under the effect of Trichloroacetic acidic solution whereas itisabout 8% under the effect the salicycilic acidic solution attackfor both SCC and NCC mixes after 62 days of treatment for bothSCC and NCC mixes respectively. The reduction percentage in flexural strengthisabout 27% and 37% under the effect of the Trichloroacetic acidic solution attack whereas itis about 59% and 79% under the effect the salicycilic acidic solution attackfor both SCC and NCC mixes respectivelyafter 62 days of treatment. The reduction percentage in splitting tensile strength is about 60% and 63% under the effect the Trichloroacetic acidic solution attack whereas it is 70% and 88% under the effect of the salicycilic acidic solution attack% for both SCC and NCC mixes after 62 days of treatment. At the age 90 days, the SCC and NCC mixes have a reductionpercentage in the cubes weight of 3% and 4% whereas there is an increasing in volume of 0.3% and 0.4% respectively under the effect of salicyclic acid solution attack.It is observed that SCC mixes offer more resistant and less deterioration against acidic solutions attack.

Abstract: Investigation methods of self-compacting concrete (SCC) in fresh state in virtue of the new Hungarian standard are summarized. The referenced testing methods of former technological guidance were finally replaced by the MSZ EN 12350:2010 standards, part 8, 9, 10, 11 and 12, however momentarily these are only available in English. Besides testing methods, the requirements of MSZ EN 206-9:2010 Additional rules for self-compacting concrete reference titled standard are precedent. Neither of the currently used and standardized testing methods is suitable for collective evaluation of each special feature of SCC, thus these should be used coinstantaneously. Results of recent research work regarding change of SCC features by adding different amount of sand aggregate are presented in this article, too.

Abstract: Concrete filled steel tube (CFT) structure has advantages of the high tensile strength and ductility of steel in addition to the high compressive strength and stiffness of concrete. This research proposes a new CFT column-CFT beam frame structure. In order to validate the cost performance of the new CFT column-CFT beam frame structure, designs were carried out for building frames using both the new CFT column-CFT beam frame structure and conventional steel frame structure. The amount of consumed materials and cost estimations of each designed new CFT and conventional steel building frame are analyzed and compared. The result shows that the new CFT column-CFT beam frame structure is able to exhibit high cost performance than conventional steel frame structure.

Abstract: This paper presents the effect of added limestone powder (LS) on the fresh and cured properties of self-compacting concrete (SCC) containing cathode ray tube glass waste. The concrete was produced using ordinary Portland cement at a water-cement (W/C) ratio of 0.38 by weight. CRT glass waste cullet was incorporated in river sand in proportions of 20 or 40%. To suppress potential viscosity effects limestone powder was added at levels of 5, 10, or 15% by weight. The slump flow time, slump flow diameter, V-funnel flow time, Marsh cone flow time, and setting time of the fresh concrete were tested, as well as the compressive strength and ultrasonic pulse velocity of the hardened concrete. The slump flow, V-funnel flow time, and Marsh cone flow increased with increasing limestone powder content, while the compressive strength and ultrasonic pulse velocity decreased. The results demonstrate that it is feasible to use limestone powder to produce SCC containing CRT glass waste as a fine aggregate replacement.

Abstract: Self-compacting lightweight concrete was developed to attain good workability, high compressive strength (at least 50 MPa), minimum cracks, and low specific weight (less than 2000 kg/m3), as well as low elastic modulus (about 30 GPa). The attention was also focused on sustainability of this construction material, which was improved by using in the mixture both GRP industrial by-product as filler and artificial (light expanded clay) or recycled (demolished concrete) as coarse aggregates replacing natural gravel. Satisfactory, if not excellent, results were obtained from the collected experimental data.