Experimental Study on Frost Resistance Durability of Lightweight Aggregate Concrete in Na2SO4 Solution

2010 ◽  
Vol 152-153 ◽  
pp. 1565-1569
Author(s):  
Jun Fang Huo ◽  
Hui Yang ◽  
Xiang Dong Shen ◽  
Xiao Xia Ji ◽  
Qi Cui
Keyword(s):  
Frost Resistance ◽  
Steel Fiber ◽  
Polypropylene Fiber ◽  
Lightweight Aggregate ◽  
Strength Loss ◽  
Interfacial Transition Zone ◽  
Lightweight Aggregate Concrete ◽  
Test Results ◽  
Aggregate Concrete ◽  
Resistance Durability

Pumice was used to make up lightweight aggregate concrete (LWAC). Frost resistance durability of LWAC in 5% Na2SO4 solution was studied. The test results showed that LWAC durability deteriorates more rapidly under freezing-thawing in salt solution than in water. The strength loss of LWAC was reduced by steel fiber and polypropylene fiber regardless of Na2SO4 solution and water. Fly ash and silica fume can improve Interfacial Transition Zone（ITZ）and the frost resistance of fibers reinforcement LWAC dramatically.

Study on Frost Resistance Durability of Lightweight Aggregate Concrete Improved by Fiber

2011 ◽  
Vol 250-253 ◽  
pp. 822-827
Author(s):  
Jun Fang Huo ◽  
Hui Yang ◽  
Yong Li Hou ◽  
Jian Jun Chu ◽  
Wei Ling Li
Keyword(s):  
Mass Loss ◽  
Frost Resistance ◽  
Steel Fiber ◽  
Polypropylene Fiber ◽  
Lightweight Aggregate ◽  
Strength Loss ◽  
Lightweight Aggregate Concrete ◽  
Aggregate Concrete ◽  
Resistance Durability ◽  
The Impact

Pumice, polypropylene fiber, steel fiber and fly ash were used to compound fiber reinforced lightweight aggregate concrete (LWAC). The effect of fibers on frost resistance durability of LWAC is studied, which including freezing-thawing in 5% Na2SO4 solution and in water. The test results show that the strength loss of LWAC is reduced with the increase in fiber fraction, but the impact of mass loss is not obvious by mixing fiber. LWAC freezing-thawing deterioration is even more serious in salt solution than in water. SEM photo show that polypropylene fiber has more stronger cementing bond with paste than steel fiber. the mass loss and strength loss are decreased significantly. By introduction silica fume can improve Interfacial Transition Zone（ITZ）and the frost resistance of fibers reinforcement LWAC dramatically.

Freeze-Thaw Model and Service Life Prediction of Hybrid Fiber Reinforced Lightweight Aggregate Concrete

2011 ◽  
Vol 250-253 ◽  
pp. 817-821 ◽  
Author(s):  
Jun Fang Huo ◽  
Da Peng Liu ◽  
Xiang Dong Shen ◽  
Jian Jun Chu ◽  
De Tian Song
Keyword(s):  
Service Life ◽  
Frost Resistance ◽  
Life Prediction ◽  
Polypropylene Fiber ◽  
Lightweight Aggregate ◽  
Service Life Prediction ◽  
Lightweight Aggregate Concrete ◽  
Hybrid Fiber ◽  
Hybrid Fibers ◽  
Aggregate Concrete

The effect of the frost resistance on hybrid fibers reinforced lightweight aggregate concrete is investigated. And hybrid fibers reinforced lightweight aggregate is that steel fiber and polypropylene fiber are selected to incorporate into. The results indicate that, hybrid fibers reinforced lightweight aggregate concrete can improve the frost resistance. The weight loss rate of hybrid fibers reinforced lightweight aggregate concrete is not better. The research to establish a model for service life prediction of hybrid fibers reinforced lightweight aggregate concrete on experimental results has been done.

Experimental Study on Mechanical Properties of Hybrid Fiber Reinforced Full Lightweight Aggregate Concrete

2011 ◽  
Vol 197-198 ◽  
pp. 911-914 ◽  
Author(s):  
Li Yun Pan ◽  
Hao Yuan ◽  
Shun Bo Zhao
Keyword(s):  
Mechanical Properties ◽  
Apparent Density ◽  
Steel Fiber ◽  
Polypropylene Fiber ◽  
Lightweight Aggregate ◽  
Lightweight Aggregate Concrete ◽  
Fiber Reinforced ◽  
Mass Content ◽  
Hybrid Fiber ◽  
Aggregate Concrete

Tests were carried out to study mechanical properties of hybrid fiber reinforced full lightweight aggregate concrete (HFRFLAC), the hybrid fiber was composed by steel fiber and polypropylene fiber, the expanded-shale and lightweight sand were used as coarse and fine aggregates. The apparent density and strengths in cubic compressive, splitting tensile and flexural tensile states of HFRFLAC were obtained. The results show that the average dry apparent density increases with the increasing cement content, which is much more affected by fraction of steel fiber by volume than mass content of polypropylene fiber; the tensile strengths increase somewhat with the increasing mass content of polypropylene fiber; all of the strengths increase with the increasing fraction of steel fiber by volume, and obvious are the enhancement of tensile strengths; there are somewhat relevance between the effects of polypropylene fiber and steel fiber on mechanical properties of HFRFLAC.

A Review on Frost Resistance of Steel Fiber Reinforced Lightweight Aggregate Concrete

2013 ◽  
Vol 438-439 ◽  
pp. 295-299 ◽  
Author(s):  
Xiao Ke Li ◽  
Wen Hui Song ◽  
Chang Yong Li
Keyword(s):  
Frost Resistance ◽  
Steel Fiber ◽  
Resistance Mechanism ◽  
Lightweight Aggregate ◽  
Steel Fibers ◽  
Mineral Admixture ◽  
Lightweight Aggregate Concrete ◽  
Fiber Reinforced ◽  
Aggregate Concrete ◽  
Cold Area

Compared with ordinay concrete, weight of lightweight aggregate concrete could be lower 20%-40% under same bearing capacity. Mixed with some given steel fibers in it, crack resistance and flexural strength will be improved. Once lightweight aggregate concrete mixed with steel fibers meets the requirements of frost resistance, it could be applied to most civil engineerings in a cold area. In this paper, the frost resistance mechanism of steel fiber reinforced lightweight aggregate concrete is introduced. The research status of frost resistance of steel fiber reinforced lightweight aggregate concrete is reviewed including the effects of water cement ratio, aggregate, mineral admixture and amount of fiber, frost resistance experimatal methods and engineering applications etc. Some further researches are prospected.

Influence of Lightweight Aggregate on Durability of High Performance Concrete

2009 ◽  
Vol 405-406 ◽  
pp. 197-203
Author(s):  
Bao Sheng Zhang ◽  
Li Juan Kong ◽  
Yong Ge
Keyword(s):  
Pore Structure ◽  
Cement Paste ◽  
Frost Resistance ◽  
High Performance ◽  
High Performance Concrete ◽  
Bound Water ◽  
Lightweight Aggregate ◽  
Normal Weight ◽  
Lightweight Aggregate Concrete ◽  
Aggregate Concrete

High performance concrete (HPC) with a water/cement ratio (w/c) of 0.32 and different lightweight aggregate (LWA) contents (0%, 25%, 50%, 75%, 100%) were prepared, and the influence of LWA on concrete frost-resistance and impermeability at different ages were studied, as well as the hydration degree, hydrated product, pattern and pore structure of the paste around aggregate. The results show that, by replacing normal weight aggregate (NWA) with 50% and 100% volume contents of pre-wetted LWA respectively, the chemical bound water of the cement paste surrounding aggregate are increased 12.1% and 22.7% as compared to concrete mixed without LWA. And at 28 days, lightweight aggregate concrete has the highest Ca(OH)2 content, whereas the 90-day Ca(OH)2 content of normal weight concrete is the highest. This proves that, with the increase of LWA content in concrete, both of the internal curing effect of pre-wetted LWA and secondary hydration effect of fly ash (FA) are strengthened, this can also be verified by the SEM study. Furthermore, the pore structure of the cement paste around aggregate can be improved consequently. The performance of frost-resistance of HPC can be improved by mixing LWA, the 90 day-frost-resistance of lightweight aggregate concrete is about 2.5 times of that of concrete mixed without LWA. The influence of LWA on the impermeability of HPC is different from normal concrete. When LWA content is more than 50%, the HPC impermeability decreased obviously, however at later age the difference between them becomes minor.

Mechanical Properties of Fiber Reinforced Lightweight Aggregate Concrete

2011 ◽  
Vol 477 ◽  
pp. 274-279 ◽  
Author(s):  
Yi Xu ◽  
Lin Hua Jiang ◽  
Hong Qiang Chu ◽  
Lei Chen
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Compressive Strength ◽  
Water Hyacinth ◽  
Steel Fiber ◽  
Polypropylene Fiber ◽  
Lightweight Aggregate ◽  
Splitting Tensile Strength ◽  
Lightweight Aggregate Concrete ◽  
Fiber Types

In this study, the effects of fiber types on the mechanical properties of lightweight aggregate concretes were investigated. Three types of fibers, namely, polypropylene fiber, steel fiber and water hyacinth (Eichhornia crassipes) fiber, and two types of lightweight aggregates, namely, expanded polystyrene and ceramsite were used. The compressive strength and splitting tensile strength of concretes were tested. The results show that both the compressive strength and the splitting tensile strength were improved by adding a reasonable volume of steel fiber and polypropylene fiber into LWAC. The addition of water hyacinth fiber had little effect on the compressive strength of LWAC, while a little increase was observed in the splitting tensile strength.

Strength and Microstructural Study of Lightweight Aggregate Concrete (LWAC) Using Lightweight Expended Clay Aggregates (LECA)

2020 ◽  
Vol 1010 ◽  
pp. 678-683
Author(s):  
Khairul Nizar Ismail ◽  
Fatihah Halim
Keyword(s):  
Lightweight Aggregate ◽  
Interfacial Transition Zone ◽  
Lightweight Aggregate Concrete ◽  
Small Scale ◽  
Strength Development ◽  
Aggregate Concrete ◽  
Microstructural Study ◽  
Digital Microscope ◽  
Crushed Aggregate ◽  
Clay Aggregates

Concrete is a composite material that consists of a cement and aggregate particles. Microstructure is the small scale structure of a material, defined as the structure of a prepared surface of material as revealed by a microscope. There is strong evidence that aggregate type is a factor in the strength of concrete. The objective of this research is to investigate the properties of concrete that are containing the lightweight expanded clay aggregates (LECA). Digital microscope was used to analyses the formation mechanism of microstructure in concrete. LECA were used in production of lightweight aggregate concrete (LWAC) with the size 50 mm x 50 mm x 50 mm. This paper deals with observation of the concrete microstructure to point out some differences that would be responsible for strength of concrete. The results show that, LECA has several improvements when compared with conventional crushed aggregate. The concrete specimens were used to validate the existence of an interfacial transition zone (ITZ) in concrete. The microstructure features are discussed with respect to their influence on the strength development of concrete.

Sign in / Sign up

Export Citation Format

Share Document