Surface Layer Parameter of Concrete in Relation to Deicing Salt Scaling Resistance

2014 ◽  
Vol 1000 ◽  
pp. 298-301 ◽  
Author(s):  
Jaroslav Urban ◽  
Michaela Kostelecká ◽  
Tomas Klecka
Keyword(s):  
Surface Layer ◽  
Porous Structure ◽  
Concrete Structure ◽  
Hardened Concrete ◽  
Deicing Salt ◽  
Salt Scaling ◽  
Layer Parameter ◽  
Concrete Mix ◽  
Gaseous Media ◽  
Scaling Resistance

The porous structure together with surface layer, made by the compaction of concrete mix designed and by the following treatment of concrete placed, has a decisive influence on the penetration of aggressive media into the inside of concrete structure. In principle, it influences the parameters of hardened concrete and the transport of liquid and gaseous media. The surface layer of concrete is contacted as the first with aggressive substances and is an entrance gate for unwanted ones.

scholarly journals Frost durability of steel fiber self-compacting concrete for pavements

2016 ◽  
Vol 11 (1) ◽  
pp. 35-42 ◽  
Author(s):  
Jerzy Wawrzeńczyk ◽  
Agnieszka Molendowska ◽  
Adam Kłak
Keyword(s):  
Steel Fibre ◽  
Air Entrainment ◽  
Hardened Concrete ◽  
Polymer Microspheres ◽  
Self Compacting Concrete ◽  
Freeze Thaw ◽  
Concrete Mix ◽  
Finished Surface ◽  
Frost Durability ◽  
Scaling Resistance

The paper presents the results from the research on self-compacting concrete with different steel fibre type addition. The reference self-compacting concrete mix with water/binder = 0.33 was prepared, then modified with steel fibres in the amounts of 0–60 kg/m3 and air entrained with polymer microspheres (40 μm diameter). The major objective of the research was to determine the effect of steel fibre and air content on the self-compacting concrete mix properties and hardened concrete frost durability. The tests also included internal cracking and scaling resistance evaluation for concrete specimens subjected to cyclic freeze-thaw process − two beams were frozen in air and two beams were partially submerged in water and then frozen. The scaling resistance was tested using the slab method on the specimens with sawn surface and on the specimens with natural finished surface. Non-air entrained steel fibrereinforced concretes, despite their high strength class (C55/67–C60/75) and medium absorption (4.34–5.11%), showed unsatisfactory resistance to internal cracking and scaling tests. The beams partially submerged in water failed after 100 freeze-thaw cycles, which confirms a significant influence of water uptake from moist environment during freeze-thaw cycles and the acceleration of the damage process. Test results indicate that air entrainment with polymer microspheres is a very effective method and allows obtaining very good air pore structure parameters and frost resistance results. The specimens with top − finished surface exhibited less damage in the scaling resistance tests in relation to the specimens with sawn surface.

Deicing salt scaling resistance of concrete incorporating supplementary cementing materials: laboratory and field test data

2008 ◽  
Vol 35 (11) ◽  
pp. 1261-1275 ◽  
Author(s):  
N. Bouzoubaâ ◽  
A. Bilodeau ◽  
B. Fournier ◽  
R. D. Hooton ◽  
R. Gagné ◽  
...  
Keyword(s):  
Field Evaluation ◽  
Outdoor Exposure ◽  
Test Procedures ◽  
Visual Evaluation ◽  
Deicing Salt ◽  
Supplementary Cementing Materials ◽  
Salt Scaling ◽  
Concrete Mixtures ◽  
Scaling Resistance ◽  
Made In

In this study, sidewalk sections were made in the field using seven concrete mixtures, applying a finishing and curing practice that is commonly used in Montréal, Canada. For each of the sidewalk sections, large slabs (1.2 m × 1.2 m) were cast from which specimens were cored and tested in the laboratory for determining their basic mechanical properties and deicing salt scaling resistance following ASTM C672 test procedures. Also, during the casting of the sidewalk, companion specimens were cast on site, using concrete from the same batch, and were subjected to the same tests as the “cored” specimens. The resistance to deicing salt scaling of these “laboratory specimens” was evaluated according to ASTM C672 and to BNQ NQ 2621–900 (2002 standard of the province of Quebec, Canada) test procedures. The results were compared with the performance of the sidewalk sections after four winters of outdoor exposure. The visual evaluation of the sidewalks after four winters has confirmed the severity of the ASTM C672 procedure and the adequateness of the BNQ procedure to better evaluate the deicing salt scaling resistance of concrete made with supplementary cementing materials (SCMs). The field evaluation should, however, continue for a longer period of time to increase the confidence in the BNQ test or to allow for changes as needed.

Deicing salt scaling resistance of concrete incorporating fly ash and (or) silica fume: laboratory and field sidewalk test data

2011 ◽  
Vol 38 (4) ◽  
pp. 373-382 ◽  
Author(s):  
N. Bouzoubaâ ◽  
A. Bilodeau ◽  
B. Fournier ◽  
R.D. Hooton ◽  
R. Gagné ◽  
...  
Keyword(s):  
Fly Ash ◽  
Silica Fume ◽  
Blended Cement ◽  
Field Evaluation ◽  
Concrete Mixture ◽  
Test Procedures ◽  
Deicing Salt ◽  
Salt Scaling ◽  
Curing Compound ◽  
Scaling Resistance

Sidewalk sections were cast in fall 2002 with three concrete mixtures that consisted of a control concrete, a concrete mixture incorporating 25% fly ash, and a concrete mixture made with a ternary blended cement (fly ash and silica fume). The curing practices consisted of using curing compound and wet burlap. For each of the sidewalk sections, laboratory specimens were cast on site using the concrete from the same batch. Large slabs (1.2 m × 0.9 m) were also cast from which specimens could be cored and tested in the laboratory for compressive strength and deicing salt scaling resistance following the ASTM and the BNQ test procedures. The results were compared to the performance of the sidewalk sections after six winters of outdoor exposure. A similar study was completed on sidewalk sections cast in spring 2002; the objective of the present study being to confirm the results of the previous investigation, and to determine the effect of the time of casting on the scaling resistance of the concrete i.e., performance of sidewalks cast in spring versus that of sidewalks cast in fall. The field evaluation showed that all the concretes cast in fall scaled relatively more than those placed in spring. Both laboratory results and field evaluations have shown that the use of a curing compound increases the scaling resistance of all the concretes investigated. The results also confirmed the adequateness of the BNQ procedure to better evaluate the deicing salt scaling resistance of concrete made with supplementary cementing materials; however, monitoring the sidewalk sections for a longer period of time is still required to confirm the above observations.

scholarly journals Consistency and mechanical properties of sustainable concrete blended with brick dust waste cementitious materials

2021 ◽  
Vol 3 (4) ◽  
Author(s):  
S. Y. Amakye ◽  
S. J. Abbey ◽  
A. O. Olubanwo
Keyword(s):  
Tensile Strength ◽  
Fresh Concrete ◽  
Environmental Benefits ◽  
Partial Replacement ◽  
Target Range ◽  
Hardened Concrete ◽  
Index Test ◽  
Demolition Waste ◽  
Concrete Mix ◽  
Brick Dust

AbstractThe reuse of waste materials in civil engineering projects has become the topic for many researchers due to their economic and environmental benefits. In this study, brick dust waste (BDW) derived from cutting of masonry bricks and demolition waste which are normally dumped as land fill is used as partial replacement of cement in a concrete mix at 10%, 20% and 30% respectively, with the aim of achieving high strength in concrete using less cement due to the environmental problems associated with the cement production. To ascertain the effects of BDW on the consistency and mechanical performance of concrete mix, laboratory investigations on the workability of fresh concrete and the strength of hardened concrete were carried out. Slump and compaction index test were carried out on fresh concrete mix and unconfined compressive strength (UCS) test and tensile strength test were conducted on hardened concrete specimen after 7, 14 and 28 days of curing. The results showed high UCS and tensile strength with the addition of 10% BDW to the concrete mix, hence achieving the set target in accordance with the relevant British standards. A gradual reduction in strength was observed as BDW content increases, however, recording good workability as slump and compaction index results fell within the set target range in accordance with relevant British standards. Findings from this study concluded that BDW can partially replace cement in a concrete mix to up to 30% igniting the path to a cleaner production of novel concrete using BDW in construction work.

Methodology for developing a combined technological process based on modifying the properties and changing the surface layer parameter

2020 ◽  
pp. 24-31
Author(s):  
V.N. Gadalov ◽  
E.A. Filatov ◽  
A.V. Filonovich
Keyword(s):  
Surface Layer ◽  
Technological Process ◽  
Acoustic Properties ◽  
Scientific Concept ◽  
Regulatory Documents ◽  
Layer Parameter ◽  
Metal Microstructure ◽  
System Errors

The article reveals information links between acoustic properties and parameters of the metal microstructure. A large number of regulatory documents and a lack of scientific concept lead to the system errors when estimating condition of both longterm operating metal and the product in the whole. The article considers methodology for developing a combined technological process based on modification of properties and change of the coatings' surface layer parameters, with an estimation of their efficiency in terms of productivity based on the criterial use of productivity principles. The analysis of technological activities for the productivity coefficient and the criterial estimates confirmed their efficiency.

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