Effect of Blending Micro and Nano Silica on the Mechanical and Durability Properties of Self-Compacting Concrete

Self-compacting concrete (SCC) is also considered as a concrete which can be placed and compacted under its own weight with little or no vibration without segregation or bleeding. The use of SCC with its improving productions techniques is increasing everyday in concrete production. It is used to facilitate and ensure proper filling and good structural performance of heavily reinforced structural members. Recently, nano particles have been gaining increasing attention and have been applied in many fields to fabricate new materials with novel functions due to their unique physical and chemical properties. Degradation of concrete members exposed to aggressive sulphuric acid environments is a key durability issue that affects the life cycle performance and maintenance costs of vital civil infrastructure. Sulphuric acid in groundwater, chemical waste or generated from the oxidation of sulphur bearing compounds in backfill can attack substructure concrete members. Moreover, concrete structures in industrial zones are susceptible to deterioration due to acid rain of which sulphuric acid is a chief component. In this work 40Mpa self-compacting concrete is developed using modified Nan-Su method of mix design. Slump flow, J-Ring, V-funnel tests are conducted to justify the fresh properties of SCC and are checked against EFNARC (2005) specifications. Specimens of dimensions 150x150x150mm were cast without nano silica and with two nano silica are added in different percentages(1%, 1.5% and 2% by weight of cement) to SCC. To justify the compressive strength for 7 and 28days, specimens are tested under axial compression. Durability properties were also studied by immersing the specimensin5% HCl and5% H2SO4. The particle packing in concrete can be improved by using Nano-silica which leads to densifying of the micro and nanostructure resulting in improved mechanical properties. Nano-silica addition to cement based materials can also control the degradation of the fundamental C-S-H (calcium-silicate-hydrate) reaction of concrete caused by calcium leaching in water as well as block water penetration and therefore lead to improvements in durability.

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Evaluating the durability properties of self compacting concrete made with coarse and fine recycled concrete aggregates

European Journal of Environmental and Civil engineering ◽

10.1080/19648189.2018.1506825 ◽

2018 ◽

Vol 24 (14) ◽

pp. 2383-2399 ◽

Cited By ~ 3

Author(s):

Kanish Kapoor ◽

Surinder Pal Singh ◽

Bhupinder Singh

Keyword(s):

Recycled Concrete ◽

Self Compacting Concrete ◽

Concrete Aggregates ◽

Recycled Concrete Aggregates ◽

Durability Properties

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Strength And Durability Properties Of Steel Fiber Reinforced Self Compacting Concrete

Turkish Journal of Computer and Mathematics Education (TURCOMAT) ◽

10.17762/turcomat.v12i5.1489 ◽

2021 ◽

Vol 12 (5) ◽

pp. 818-826

Author(s):

Sumith Vangara, S Siva Rama Krishna, Venu Malagavelli, K.Tarunkumar, A. Jagadish Babu

Keyword(s):

Steel Fiber ◽

Design Procedure ◽

Steel Fibers ◽

Second Phase ◽

Initial Surface ◽

Fiber Reinforced ◽

Acid Attack ◽

Self Compacting Concrete ◽

Surface Absorption ◽

Durability Properties

In this present study the durability characteristics of Steel fiber reinforced Self compacting concrete (SFRSCC) is determined for M30 and M40 grade concrete mixes. Along with durability strength and sorptivity is carried out and comparison is made with Plane self-compacting concrete (SCC) by chemical resistances, Initial Surface Absorption Test (ISAT). In the present study, the rational mix design procedure for self-compacting concrete is used. SCC mixes contains large quantity of powder (material whose parcel size is 0.125 mm) to maintain the plastic yield of the properties of fresh concrete as per the general guidelines for design of SCC mixes given in the EFNARC (2005). The present project consists of two phases. In the first phase, SCC mixes for different grades are developed without steel fibers and with steel fibers. The mechanical properties like compressive strength of the different grades were studied. In the second phase, based on the experimental results, durability properties were studied with the using of specimens of size 100 mm × 100 mm × 100 mm. Durability studies like Acid attack factors, Acid-Durability factors, Sulphate attack factors, Sorptivity are studied for the Plain SCC and steel Fiber Reinforced SCC and a comparison is made.

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