Test Research on Mechanical Property of GFRP Bolt under Freeze-Thaw Cycle Conditions

2012 ◽  
Vol 531-532 ◽  
pp. 689-694
Author(s):  
Xie Xing Tang ◽  
Xiao Yong Luo ◽  
Qi Sun ◽  
Ya Chuan Kuang
Keyword(s):  
Mechanical Property ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Ultimate Tensile Strength ◽  
Test Results ◽  
Freeze Thaw ◽  
Thaw Cycle ◽  
Freeze Thaw Cycle ◽  
The Times

In this paper, GFRP bolts in diameter of 25mm are tested through freeze-thaw cycle by 50, 100 and 150 times to study their change law of appearance, weight, strength and elastic modulus. As reflected from the test results, after the freeze-thaw cycle, the appearance and weight of GFRP bolts are basically not changed. As the freeze-thaw cycle increases from 50 times to 100 times, the strength of bolts decreases gradually. After 50, 100 and 150 times of freeze-thaw cycle, the ultimate tensile strength of bolt decreases by 2.82%, 4.35% and 8.84%, respectively. During the process that the times of freeze-thaw cycle increase from 50 to 100, the elastic modulus of GFRP bolts grows gradually. After 50, 100 and 150 times of freeze-thaw cycle, the elastic modulus increases by 1.42%, 2.68% and 3.92%, respectively. The freeze-thaw cycle leads to embrittlement of GFRP materials and weakness of ductility, while not obviously.

Studies the Properties of Polyaspartic Polyurea Coated Concrete under Coaction of Salt Fog and Freeze-Thaw

2012 ◽  
Vol 455-456 ◽  
pp. 781-785
Author(s):  
Ping Lu ◽  
Xin Mao Li ◽  
Xue Qiang Ma ◽  
Wei Bo Huang
Keyword(s):  
Elastic Modulus ◽  
Frost Resistance ◽  
Dynamic Elastic Modulus ◽  
Freeze Thaw ◽  
Decrease Rate ◽  
Thaw Cycle ◽  
Freeze Thaw Cycle ◽  
Salt Fog

. This paper mainly studied the properties of PAE polyurea coated concrete under coactions of salt fog and freeze-thaw. After exposed salt fog conditions for 200d, T3, B2, F2 and TM four coated concrete relative dynamic elastic modulus have small changes, but different coated concrete variation amplitude is different. T3 coated concrete after 100 times of freeze-thaw cycle the relative dynamic elastic modulus began to drop, 200 times freeze-thaw cycle ends, relative dynamic elastic modulus variation is the largest, decrease rate is 95%, TM concrete during 200 times freeze-thaw cycle, relative dynamic elastic modulus almost no change, B2 concrete and F2 concrete the extent of change between coating T3 and TM. After 300 times the freeze-thaw cycle coated concrete didn't appear freeze-thaw damage phenomenon. Four kinds of coating concrete relative dynamic elastic modulus variation by large to small order: T3 coated concrete > B2 coated concrete >F2 coated concrete > TM coated concrete, concrete with the same 200d rule. Frost resistance order, by contrast, TM coated concrete > B2 coated concrete > F2 coated concrete > T3 coated concrete.

Research of Steel Fiber Self-Compacting Concrete Frost Resistance

2012 ◽  
Vol 174-177 ◽  
pp. 721-725 ◽  
Author(s):  
Ming Bao Gao ◽  
Yan Ru Zhao ◽  
Xiao Yan He
Keyword(s):  
Elastic Modulus ◽  
Frost Resistance ◽  
Steel Fiber ◽  
Concrete Specimen ◽  
Test Method ◽  
Dynamic Elastic Modulus ◽  
Self Compacting Concrete ◽  
Freeze Thaw ◽  
Thaw Cycle ◽  
Freeze Thaw Cycle

With the fast freeze-thaw test method, the c50 steel fiber self-compacting concrete was carried out 300 tests of freeze-thaw cycle. In the process of freeze-thaw cycles, it determined by the quality of the concrete specimen, dynamic elastic modulus and strength, and analyzed the steel fibers and their different contents on frost resistance of self-compacting concrete impact. The results showed that: steel fiber self-compacting concrete in freeze-thaw cycle can play constrained role in the quality loss, dynamic elastic modulus and intensity, and can significantly improve the self-compacting concrete frost resistance. Within a certain range, the more steel fiber, the stronger of frost resistance.

Durability Test Research of Asphalt Mixture with Rubber Particles under the Condition of Freeze-Thaw Cycle

2014 ◽  
Vol 919-921 ◽  
pp. 1096-1099 ◽  
Author(s):  
Hong Yu Xu ◽  
Song Yang Dang ◽  
De Yong Cui
Keyword(s):  
Tensile Strength ◽  
Void Fraction ◽  
Rubber Particle ◽  
Asphalt Mixture ◽  
Splitting Tensile Strength ◽  
Particle Content ◽  
Freeze Thaw ◽  
Thaw Cycle ◽  
Rubber Particles ◽  
Freeze Thaw Cycle

Influence of freeze-thaw cyclic on the durability of asphalt mixture with rubber particles was researched by experiment. Based on the typed AC-13 continuous dense graded aggregate, adding the amount of 1%~3% of rubber particles into graded aggregate, the splitting tensile strength and the void fraction of asphalt mixture with rubber particles under the condition of freeze-thaw cycle were measured. The test results show that the splitting tensile strength decreases and the void fraction increases with the increase of the number of freeze-thaw cycle. With the increase of rubber particle content, the splitting tensile strength decreases and the void fraction increases under the same number of freeze-thaw cycle. When rubber particles are added to graded aggregate, the splitting tensile strength of asphalt mixture is reduced to some extent. And when the rubber particle content attains 2%, the TSR (tensile strength ratio) achieves the optimal value.

scholarly journals Equation for the Degradation of Uniaxial Compression Stress of Concrete due to Freeze-Thaw Damage

2019 ◽  
Vol 2019 ◽  
pp. 1-8 ◽  
Author(s):  
Xiaolin Yang ◽  
Genhui Wang ◽  
Shiwu Gao ◽  
Min Song ◽  
Anqi Wang
Keyword(s):  
Concrete Strength ◽  
Damage Variable ◽  
Curved Surface ◽  
Large Temperature ◽  
Test Results ◽  
Stress Strain ◽  
Cycle Number ◽  
Freeze Thaw ◽  
Thaw Cycle ◽  
Freeze Thaw Cycle

To study the freeze-thaw damage characteristics of concrete, the uniaxial compressive tests of concrete under different number of freeze-thaw cycles were conducted, and the damage variable of freeze-thaw was obtained. The test results showed that the stress was a function of strain and freeze-thaw damage variable, and it can describe the degradation of concrete strength. Meanwhile, the equation for the stress-strain curved surface about strain and freeze-thaw damage variable was also proposed in this paper. The derivative function of the stress-strain curved surface equation with respect to strain presented the change of elastic modulus with the increase of freeze-thaw cycle number. Equation proposed in this paper can be used for predicting the concrete lifetime effectively in cold and large temperature difference regions.

Low Temperature Performance of Fiberglass Geogrid

2012 ◽  
Vol 443-444 ◽  
pp. 632-636
Author(s):  
Yong Li Xu ◽  
Bai Zhen Ming Zhang ◽  
Le Tao ◽  
Zhen Zhen Xing
Keyword(s):  
Tensile Strength ◽  
Low Temperature ◽  
Water Immersion ◽  
Temperature Drop ◽  
Freeze Thaw ◽  
Temperature Performance ◽  
Thaw Cycle ◽  
Freeze Thaw Cycle ◽  
Shearing Strength ◽  
Low Temperature Performance

The tensile test to the fiberglass geogrid had been carried on, in the normal temperature, the low temperature, the water immersion, the freezing and the freeze-thaw cycle and so on conditions. The results indicated, the fiberglass geogrid had achieved saturated after been immersed 12h, the water absorption was about 20%, the tensile strength reduced approximately 80%; the tensile strength was dropped slightly on the next freezing test and the freeze-thaw cycle test. So it could be stated that the fiberglass geogrid had the good low temperature performance. Then the interlaminar shearing test had been conducted in the different temperature to the composite structure in which the fiberglass geogrid was laid or not. The result showed that the interlaminar shearing strength had weaken about 20% when laid down the fiberglass geogrid, and along with temperature drop, the shearing strength increased gradually. This research provide the reference for used the fiberglass geogrid correctly in the cold region, had great practical value.

The Mechanics Performance of C30 Concrete with Manufactured-Sand under Condition of Freeze-Thaw Cycles

2011 ◽  
Vol 71-78 ◽  
pp. 1036-1039
Author(s):  
Gui Feng Liu ◽  
Zheng Fa Chen ◽  
Xue Xing Chen
Keyword(s):  
Elastic Modulus ◽  
Acid Corrosion ◽  
Experimental Studies ◽  
Raw Material ◽  
Dynamic Elastic Modulus ◽  
Manufactured Sand ◽  
Freeze Thaw ◽  
Thaw Cycle ◽  
Mechanics Performance ◽  
Freeze Thaw Cycle

Although many people discussed the strength and durability of concrete with natural sand in severe environment, few people investigated the mechanics performance of concrete with manufactured-sand under condition of freeze-thaw cycle, at present. Experimental studies on C30 concrete with manufactured-sand were carried out under condition of freeze-thaw cycle, which based on the testing of raw material performance and concrete mix ration, in this paper. Comparative studies on the changing laws of the mass, strength and the relative dynamic elastic modulus of concrete were developed in three cases which were freeze-thaw cycle, freeze-thaw cycle and acid corrosion and freeze-thaw cycle and alkali corrosion. The test results showed that the mass, strength and the relative dynamic elastic modulus of concrete with manufactured-sand decreased evidently with the increasing of times of freeze-thaw cycle. The durability of acid and alkali-resistant of concrete with manufactured-sand was also remarkably weakened due to the action of freeze-thaw cycle. The capability of acid and alkali-resistant of the concrete was decreased with the increasing of times of freeze-thaw cycle and the anti-acid capability was decreased more seriously.

scholarly journals Mechanical Properties and Micro Structure of Cement Concrete in Freeze-Thaw Environment

2021 ◽  
Vol 233 ◽  
pp. 01011
Author(s):  
Xin jian Lv ◽  
Lei Yu ◽  
Ming ming Chai
Keyword(s):  
Compressive Strength ◽  
Elastic Modulus ◽  
Pore Structure ◽  
Fresh Water ◽  
Pore Diameter ◽  
Dynamic Elastic Modulus ◽  
Freeze Thaw ◽  
Salty Water ◽  
Thaw Cycle ◽  
Freeze Thaw Cycle

In order to find the declay law of mechanical property and the performance difference after salty water and fresh water freeze-thaw cycle, freeze-thaw cycle environments under the salty water and fresh water are simulated. The compressive strength, dynamic elastic modulus and the mass lost are tested. The pore structure parameters are also tested by MIP. Plot the pore diameter distribution curve. The result shows that the compressive strength and dynamic elastic modulus are all decreased. The degree of these two properties decreasing under salty water freeze and thaw recycle is more than the one under fresh water. The parameters of porosity and critical pore diameter become larger. The amount of pores whose diameter is between 100nm and 1000nm increase. The amount of pores whose diameter is under 100nm decrease. The deteriorate degree of pore structure is deeper in salty water than in fresh water.

scholarly journals Study on Long-Term Dynamic Mechanical Properties and Degradation Law of Sandstone under Freeze-Thaw Cycle

2020 ◽  
Vol 2020 ◽  
pp. 1-10
Author(s):  
Qingsong Pu ◽  
Junhong Huang ◽  
Fuling Zeng ◽  
Yi Luo ◽  
Xinping Li ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Elastic Modulus ◽  
Strain Rate ◽  
Air Pressure ◽  
Freeze Thaw ◽  
Dynamic Mechanical ◽  
Thaw Cycle ◽  
Freeze Thaw Cycle ◽  
Dynamic Compressive Strength

This study is based on the tunnel-face slope engineering of Dongfeng tunnel in Shanxi section of China’s Shuozhou-Huanghua Railway. The sandstone specimens in the perennial freeze-thaw zone of the slope were collected to carry out freeze-thaw cycle static physical mechanics test and split Hopkinson pressure bar (SHPB) dynamic mechanical test. Thus, the damage process of sandstone under freeze-thaw cycle and impact load is studied. Also, the dynamic compressive strength and dynamic elastic modulus of sandstone are analysed under different loading strain rates and freeze-thaw cycle based on LS-DYNA, a dynamic finite element program. The results showed that the dynamic compressive strength of sandstone subjected to multiple freeze-thaw cycles under 0.04 MPa air pressure has a greater damage ratio than that under 0.055 MPa and 0.07 MPa air pressure, which was more likely to cause damage to slope sandstone than in actual engineering; the dynamic compressive strength and elastic modulus of sandstone decrease greatly within a certain range of freeze-thaw cycles and loading strain rate, leading to significant deterioration. When the freeze-thaw cycle exceeded 200 times and the strain rate was greater than 200 s−1, the physical and mechanical properties of sandstone gradually tended to be stable.

Experimental Study on Freeze-Thaw Resistance of Concrete with Proto-Machine-Made Sand

2011 ◽  
Vol 71-78 ◽  
pp. 4361-4364 ◽  
Author(s):  
Xiao Yan Zhang ◽  
Xin Xin Ding ◽  
Shun Bo Zhao ◽  
Zhan Fang Ge
Keyword(s):  
Experimental Study ◽  
Elastic Modulus ◽  
Mass Loss ◽  
Source Rock ◽  
Crushed Stone ◽  
Dynamic Elastic Modulus ◽  
Cycle Times ◽  
Freeze Thaw ◽  
Thaw Cycle ◽  
Freeze Thaw Cycle

Experiments were conducted to study the effects of source rock state and stone powder on freeze-thaw resistance of concrete with proto-machine-made sand, the strength grade of concrete was C50, the source rock states were gravel and crushed stone, the contents of stone powder in sand were 5%, 9% and 13% respectively. The values of relative dynamic elastic modulus and mass of concrete at different freeze-thaw cycle times were measured, the reduction of relative dynamic elastic modulus and mass loss were calculated to evaluate the freeze-thaw resistance of concrete. The results show that freeze-thaw resistances are controlled by the reduction of relative dynamic elastic modulus of concrete, which are good of concrete with proto-machine-made sand of gravel and crushed stone, and increases with the increasing content of stone powder in sand made of gravel. The reasons leading to difference of freeze-thaw resistance of concrete with sand made of gravel and crushed stone are discussed.

Experimental Study on Freeze-Thaw Resistance Durablilty of High Performance Concrete

2010 ◽  
Vol 168-170 ◽  
pp. 393-397 ◽  
Author(s):  
Jun Fang Huo ◽  
Xiao Xia Ji ◽  
Hui Yang
Keyword(s):  
Fly Ash ◽  
Large Volume ◽  
High Performance ◽  
High Performance Concrete ◽  
Test Results ◽  
Freeze Thaw ◽  
Thaw Cycle ◽  
Freeze Thaw Cycle ◽  
Resistance Performance ◽  
Maximum Weight Loss

Freeze-thaw cycle experiments on high performance concrete were carried out while cement was respectively replaced by fly ash for 30%～50%. The test results showed that maximum weight loss rate of concrete was 1.78% and minimum relative dynamic elastic modulus was 94.08% after 300 freeze-thaw cycles for high performance concrete based on low water-cement ratio, efficient air-water-reducing agent and large quantities of industrial waste fly ash. The test data were far less than limits of 5% and 60% in specification. Freeze-thaw resistance performance of high performance concrete with large volume fly ash was excellent according to test results. The high performance concrete with large volume fly ash can meet the requirements of frost resistance performance of concrete in the cold regions. Particularly, it can be fit for the railway concrete engineering.

Sign in / Sign up

Export Citation Format

Share Document