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Self-compacting concrete has gained a wide range of applications as a result of its unique properties, which can offer high strength and durable type of concrete with the proper selection of the raw materials. The purpose of this study was to show the effect of the use of high dosage of air entraining admixture on the properties of self-compacting concrete. An experimental investigation on the frost-salt scaling resistance of conventional and air entraining self-compacting concrete incorporating slag-blended cement and supplementary cementitious materials was carried out. Further fresh and hardened properties tests including slump flow, V-funnel, compressive strength, splitting tensile strength, air void characteristics and water absorption tests were performed to obtain an objective evaluation between air and non-air entrained self-compacting concrete mixtures. Air void characteristics were evaluated through the automated image analysis procedure to enrich this investigation. Results indicate the following: the air entraining admixture highly decreased the compressive strength up to 52% and the metakaolin was the governing supplementary cementitious material concerning the scaling resistance and water absorption in comparison with the silica fume. [ABSTRACT FROM AUTHOR]

the use of supplementary cementing materials in concrete technology may help reducing the large carbon-dioxide emission that is resulted from the production of Portland cements. the supplementary cementing materials can be classified as hydraulic additives, pozzolanic additives and inert additives. the supplementary cementing materials form calcium-silicate-hydrates and calcium-aluminate-hydrates with the calcium hydroxide available due to Portland cement hydration. Most active supplementary cementing materials are the silica fume and the metakaolin. the literature indicates that the application of silica fume or metakaolin improves the durability of concrete due to the finer pore microstructure that results lower porosity, lower permeability, higher strength, higher resistance against water penetration and higher resistance to acidic solutions. the present paper is the first part of a series of papers dealing with conventional and self compacting concretes containing silica fume or the metakaolin supplementary cementing materials. the first part gives a literature review of the supplementary cementing materials tested. the second part summarizes own experimental results. [ABSTRACT FROM AUTHOR]

The use of supplementary cementing materials in concrete technology may help reducing the large carbon-dioxide emission that is resulted from the production of Portland cements. The supplementary cementing materials can be classified as hydraulic additives, pozzolanic additives and inert additives. The supplementary cementing materials form calcium-silicate-hydrates and calcium-aluminate-hydrates with the calcium hydroxide available due to Portland cement hydration. Most active supplementary cementing materials are the silica fume and the metakaolin. The literature indicates that the application of silica fume or metakaolin improves the durability of concrete due to the finer pore microstructure that results lower porosity, lower permeability, higher strength, higher resistance against water penetration and higher resistance to acidic solutions. The present paper is the first part of a series of papers dealing with conventional and self compacting concretes containing silica fume or the metakaolin supplementary cementing materials. The first part gives a literature review of the supplementary cementing materials tested. The second part summarizes own experimental results. [ABSTRACT FROM AUTHOR]

Traditionally, the Glasstec is organized in every second year in Düsseldorf and is the largest Glass exhibition in Europe. Connected to this trade fare, numerous international conferences organized as well: Solar Meets Glass, International Architecture Congress and Engineered Transparency International Conference at Glasstec, which are located in the Messe Düsseldorf exhibition and congress centre. The last conference has been organized for the third time which was the destination of the authors besides of the Glasstec. Present report focuses on the novelties of the Glasstec exhibition in year 2014 and the international scientific conferences from the aspect of civil engineering. [ABSTRACT FROM AUTHOR]

In case of HPC the application of silica fume is often necessary. Behaviour of concrete with silica fume at high temperatures is different from that of conventional concrete. As a part of our study, experiments were carried out in order to observe the behaviour of concrete specimens exposed to fire. During the experiments both the residual compressive strength and residual flexural strength of the specimens were determined after being exposed to high temperature. Parameters of the experiment were the following: silica fume content (0 mc%, 3 mc%, 9 mc%), cement content (400 kg/m³; 436 kg/m³), water-cement ratio (w/c = 0,35; 0,36; 0,38), water-binder ratio (w/b = 0,35; 0,33; 0,30), maximum temperature (20 °C; 50 °C; 150 °C; 300 °C; 500 °C; 1000 °C). Results in case of constant w/c ratio and constant cement content: increasing the amount of silica fume is unfavourable for the relative residual compressive strength. The relative residual flexural strength also changes disadvantageously in case of lower temperature exposure (20-150 °C) and increased silica fume content. In case of higher temperature exposure (more than 150 °C) addition of 3 mc% silica fume to the mixture proved to be advantageous. Results in case of constant water-binder ratio: if silica fume is added, while water-binder ratio is kept constant (mixtures M6 and M4) the relative residual compressive strength does not changes considerably but the relative residual flexural strength increases. In case of 9 mc% silica fume content lower w/c ratio increases the initial compressive strength, on the other hand decreases the relative residual compressive strength after elevated temperature exposure. If the silica fume content is 9 mc%, the relative residual flexural strength is not affected by the different w/c ratios. The experiments also proved that the addition of silica fume to a concrete mixture decreases the risk of spalling, consequently increases the fire resistance. [ABSTRACT FROM AUTHOR]

Under load, the number of fissures in concrete or reinforced concrete increases, and such cracks will be the starting points of failure. In order to understand failure of such structures, the analysis of the stress state of crack tips is necessary, which is the subject mater of fracture mechanics. Due to material inhomogeneity and different modular coordination, the fracture analysis of concrete is more complex than the original tests devised for metals. While methods and specimens have been developed for tension failure (type I), the mode of examining shear failure (type II) has not yet been unequivocally established. This paper and its sequels focus on the analysis and test procedures of a new, compact specimen for examining the KIIC strength intensity factor. [ABSTRACT FROM AUTHOR]

Under load, the number of fissures in concrete or reinforced concrete increases, and such cracks will be the starting points of failure. In order to understand failure of such structures, the analysis of the stress state of crack tips is necessary, which is the subject mater of fracture mechanics. Due to material inhomogeneity and different modular coordination, the fracture analysis of concrete is more complex than the original tests devised for metals. While methods and specimens have been developed for tension failure (type I), the mode of examining shear failure (type II) has not yet been unequivocally established. This paper and its sequels focus on the analysis and test procedures of a new, compact specimen for examining the KIIC strength intensity factor. [ABSTRACT FROM AUTHOR]

Acute myeloid leukemia (AML) is a rapidly progressive hematological malignancy that is difficult to cure. The prognosis is poor and treatment options are limited in case of relapse. A comprehensive assessment of current disease burden and the clinical efficacy of non-intensive therapies in this population are lacking. We conducted two systematic literature reviews (SLRs). The first SLR (disease burden) included observational studies reporting the incidence and economic and humanistic burden of relapsed/refractory (RR) AML. The second SLR (clinical efficacy) included clinical trials (phase II or later) reporting remission rates (complete remission [CR] or CR with incomplete hematologic recovery [CRi]) and median overall survival (mOS) in patients with RR AML or patients with de novo AML who are ineligible for intensive chemotherapy. For both SLRs, MEDLINE ® /Embase ® were searched from January 1, 2008 to January 31, 2020. Clinical trial registries were also searched for the clinical efficacy SLR. After screening, two independent reviewers determined the eligibility for inclusion in the SLRs based on full-text articles. The disease burden SLR identified 130 observational studies. The median cumulative incidence of relapse was 29.4% after stem cell transplant and 46.8% after induction chemotherapy. Total per-patient-per-month costs were $28,148-$29,322; costs and health care resource use were typically higher for RR versus non-RR patients. Patients with RR AML had worse health-related quality of life (HRQoL) scores than patients with de novo AML across multiple instruments, and lower health utility values versus other AML health states (i.e. newly diagnosed, remission, consolidation, and maintenance therapy). The clinical efficacy SLR identified 50 trials (66 total trial arms). CR/CRi rates and mOS have remained relatively stable and low over the last 2 decades. Across all arms, the median rate of CR/CRi was 18.3% and mOS was 6.2 months. In conclusion, a substantial proportion of patients with AML will develop RR AML, which is associated with significant humanistic and economic burden. Existing treatments offer limited efficacy, highlighting the need for more effective non-intensive treatment options., Competing Interests: Esther Oliva has received honoraria from AbbVie, Alexion, Amgen, Apellis, Celgene, and Novartis, and has served on the speakers’ bureau for Celgene and Novartis. Sarah Ronnebaum, Omer Zaidi, and Dipen Patel are employees of OPEN Health, which received funding by Celgene Corporation to conduct the review. Salem Abi Nehme and Clara Chen are employees and stockholders of Bristol Myers Squibb. Salem Abi Nehme was an employee of Celgene Corporation at the time the research was initiated. Antonio Almeida has received honoraria from Bristol Myers Squibb, and has served as a speaker and consultant for AbbVie and Novartis., (AJBR Copyright © 2021.)