Calculation Methods on Crack Resistance Capacity of SRUHSC Column to SRC Beam Joint Subjected to Reversal Cycle Load

2010 ◽  
Vol 152-153 ◽  
pp. 1835-1838
Author(s):  
Ju Zhang ◽  
Chang Wang Yan ◽  
Jin Qing Jia
Keyword(s):  
Crack Resistance ◽  
High Strength Concrete ◽  
High Strength ◽  
Test Results ◽  
Steel Reinforced Concrete ◽  
Strength Concrete ◽  
Concrete Frame ◽  
Seismic Area ◽  
Resistance Performance ◽  
Good Agreement

In the joint core regions of steel reinforced ultra high strength concrete frame, the forces are complicated. In seismic area or under some exceptional conditions, it is difficult to repair for joint when cracks occur, so crack resistance performance is important. Based on the experiment of steel reinforced ultra high strength concrete (SRUHSC) column to steel reinforced concrete (SRC) beam joint subjected to reversal cycle load, the crack resistance capacity is studied and applied calculation method for crack resistance capacity is proposed. Compared with the test results, the calculated results are in good agreement with them.

Crack Resistance of Connections of Cross Shaped Steel Encased Ultra High-Strength Concrete Column to RC Beam under Cycle Loads

2010 ◽  
Vol 150-151 ◽  
pp. 1005-1008
Author(s):  
Chang Wang Yan ◽  
Jin Qing Jia ◽  
Ju Zhang
Keyword(s):  
Crack Resistance ◽  
High Strength Concrete ◽  
Engineering Application ◽  
Load Ratio ◽  
High Strength ◽  
Rc Beam ◽  
Strength Concrete ◽  
Axial Load Ratio ◽  
Resistance Performance ◽  
Good Agreement

In order to investigate the crack resistance capacity of cross shaped steel encased ultra high-strength concrete (CSSEUHSC) column to reinforced concrete (RC) beam connection subjected to reversal cycle load, six interior joint specimens were tested with various axial load ratio nt and volumetric stirrup ratio ρv. A discussion on the crack resistance capacity was presented. Calculation methods of crack resistance capacity were deduced and calculating results were in good agreement with the experimental results. The research results indicated that parameters of CSSEUHSC column to RC beam connection with better crack resistance performance may be referred for engineering application.

scholarly journals Study of Post-Cracking Torsional Behaviour of High-Strength Reinforced Concrete Beams with a Ferrocement Wrap

2014 ◽  
Vol 22 (3) ◽  
pp. 1-12 ◽  
Author(s):  
Gopal Charan Behera ◽  
Tippabhotla Durga Gunneswara Rao ◽  
Chittem Butchi Kameswara
Keyword(s):  
Material Properties ◽  
High Strength Concrete ◽  
Concrete Beams ◽  
High Strength ◽  
Reinforced Concrete Beams ◽  
Test Results ◽  
Strength Concrete ◽  
Truss Model ◽  
Effective Use ◽  
Good Agreement

Abstract The post-cracking behaviour of structures subjected to torsion can be well predicted by Hsu’s softened truss model. The softened truss model is applicable to structures having symmetry in their material properties on all four sides. Wrapping on three faces is a common phenomenon when the top face is provided with a flange or slab. Such a wrapping on three faces of a beam is referred to as a “U” wrap. “U” wraps are better wrapping strategies for distressed structures, as their top face is not accessible for many structures. The material property of an unwrapped face differs from the rest of wrapped faces. For the effective use of wrapping, the unwrapped face needs to be provided with a material having a higher resistance to tension and shear. For this, high-strength concrete in the core is a better option. Here, an attempt is made to predict the torsional capacity of “U” wrapped high-strength concrete beams having an asymmetry in the material using a softened truss model with suitable modifications of the material properties. Efficient algorithms are proposed for the solution of simultaneous equations. The predictions are found to be in good agreement with the experimental test results

Effects of Nano-CaCO3 on the Compressive Strength and Microstructure of High Strength Concrete in Different Curing Temperature

2011 ◽  
Vol 121-126 ◽  
pp. 126-131 ◽  
Author(s):  
Qing Lei Xu ◽  
Tao Meng ◽  
Miao Zhou Huang
Keyword(s):  
Compressive Strength ◽  
Low Temperature ◽  
High Strength Concrete ◽  
High Strength ◽  
Curing Temperature ◽  
Test Results ◽  
Strength Concrete ◽  
Calcium Nitrite ◽  
Orientation Index ◽  
Early Strength

In this paper, effects of nano-CaCO3 on compressive strength and Microstructure of high strength concrete in standard curing temperature(21±1°C) and low curing temperature(6.5±1°C) was studied. In order to improve the early strength of the concrete in low temperature, the early strength agent calcium nitrite was added into. Test results indicated that 0.5% dosage of nano-CaCO3 could inhibit the effect of calcium nitrite as early strength agent, but 1% and 2% dosage of nano-CaCO3 could improve the strength of the concrete by 13% and 18% in standard curing temperature and by 17% and 14% in low curing temperature at the age of 3days. According to the XRD spectrum, with the dosage up to 1% to 2%, nano-CaCO3 can change the orientation index significantly, leading to the improvement of strength of concrete both in standard curing temperature and low curing temperature.

Effect of Chopped Basalt Fiber on the Fresh and Hardened Properties of Fly Ash High Strength Concrete

2014 ◽  
Vol 567 ◽  
pp. 381-386 ◽  
Author(s):  
Nasir Shafiq ◽  
Muhd Fadhil Nuruddin ◽  
Ali Elheber Ahmed Elshekh ◽  
Ahmed Fathi Mohamed Salih
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
High Strength Concrete ◽  
Basalt Fiber ◽  
High Strength ◽  
Progressive Increase ◽  
Test Results ◽  
Strength Concrete ◽  
Hardened Properties ◽  
Chopped Basalt Fiber

In order to improve the mechanical properties of high strength concrete, HSC, several studies have been conducted using fly ash, FA. Researchers have made it possible to achieve 100-150MPa high strength concrete. Despite the popularity of this FAHSC, there is a major shortcoming in that it becomes more brittle, resulting in less than 0.1% tensile strain. The main objective of this work was to evaluate the fresh and hardened properties of FAHSC utilizing chopped basalt fiber stands, CBFS, as an internal strengthening addition material. This was achieved through a series of experimental works using a 20% replacement of cement by FA together with various contents of CBFS. Test results of concrete mixes in the fresh state showed no segregation, homogeneousness during the mixing period and workability ranging from 60 to 110 mm. Early and long terms of compressive strength did not show any improvement by using CBFS; in fact, it decreased. This was partially substituted by the effect of FA. Whereas, the split and flexural strengths of FASHC were significantly improved with increasing the content of CBFS as well as the percentage of the split and flexural tensile strength to the compressive strength. Also, test results showed a progressive increase in the areas under the stress-strain curves of the FAHSC strains after the CBFS addition. Therefore, the brittleness and toughness of the FAHSC were enhanced and the pattern of failure moved from brittle failure to ductile collapse using CBFS. It can be considered that the CBFS is a suitable strengthening material to produce ductile FAHSC.

Properties of High Strength Fibre Reinforced Concrete Using Ultra Fine Slag

2016 ◽  
Vol 857 ◽  
pp. 183-188
Author(s):  
C. Mohan Lal ◽  
Vontary Sai Srujan Reddy
Keyword(s):  
High Strength Concrete ◽  
Steel Fibre ◽  
High Strength ◽  
Target Strength ◽  
Partial Replacement ◽  
Fibre Reinforced Concrete ◽  
Test Results ◽  
Design Requirement ◽  
Split Tensile Strength ◽  
Strength Concrete

High strength concrete has become a design requirement in recent years due to increase in number of infrastructure projects. This paper presents the effect of incorporating Ultra Fine Slag (UFS) and steel fibre to obtain high strength concrete. To achieve target strength of about 80 MPa, it is proposed to the replacement of cement of 10%, 20% and 30% with UFS and incorporating 0.5% and 1.0% fibre in concrete. An experimental investigation is carried out to find the mechanical properties of the concrete. From the test results, it was observed that a compressive strength of 95 MPa was achieved at 30% replacement of cement with UFS and 1.0% fibre content. In addition, there was a significant improvement in split tensile strength and flexural strength of the concrete. This study demonstrates that a high strength concrete can be obtained from partial replacement of cement with UFS and addition of steel fibre.

Seismic behaviour of prestressed high-strength concrete piles under combined axial compression and cyclic horizontal loads

2018 ◽  
Vol 22 (5) ◽  
pp. 1089-1105 ◽  
Author(s):  
Xizhi Zhang ◽  
Sixin Niu ◽  
Jia-Bao Yan ◽  
Shaohua Zhang
Keyword(s):  
Finite Element ◽  
Axial Compression ◽  
High Strength Concrete ◽  
High Strength ◽  
Element Model ◽  
Test Results ◽  
Seismic Behaviour ◽  
Strength Concrete ◽  
Concrete Piles ◽  
Concrete Pile

In order to simulate the seismic behaviour of the prestressed high-strength concrete piles under working state, six full-scale prestressed high-strength concrete piles were tested under combined axial compression and cyclic horizontal loads. Different axial compression levels and prestressing levels of prestressed tendons were studied in this test programme. The failure mode, bending resistance, displacement ductility, stiffness degradation and energy dissipation of the prestressed high-strength concrete piles under different loading scenarios were measured and analysed. Test results indicated that the axial compression ratio and prestressing level of prestressed tendon significantly influenced the seismic performance of prestressed high-strength concrete piles. Theoretical models were developed to predict cracking, yielding and ultimate bending resistances of the prestressed high-strength concrete pile under combined compression and bending. Finite element model was also developed to simulate the ultimate strength behaviour of the prestressed high-strength concrete pile under combined compression and flexural bending. The accuracies of the theoretical and finite element model were checked through validations of their predictions against the reported test results.

scholarly journals A Study on the Thermal Properties of High-Strength Concrete Containing CBA Fine Aggregates

Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1493 ◽  
Author(s):  
In-Hwan Yang ◽  
Jihun Park
Keyword(s):  
Thermal Conductivity ◽  
Compressive Strength ◽  
Thermal Properties ◽  
Ultrasonic Velocity ◽  
High Strength Concrete ◽  
High Strength ◽  
Unit Weight ◽  
Test Results ◽  
Strength Concrete ◽  
Fine Aggregates

The thermal conductivity of concrete is a key factor for efficient energy consumption in concrete buildings because thermal conductivity plays a significant role in heat transfer through concrete walls. This study investigated the effects of replacing fine aggregates with coal bottom ash (CBA) and the influence of curing age on the thermal properties of high-strength concrete with a compressive strength exceeding 60 MPa. The different CBA aggregate contents included 25%, 50%, 75%, and 100%, and different curing ages included 28 and 56 days. For concrete containing CBA fine aggregate, the thermal and mechanical properties, including the unit weight, thermal conductivity, compressive strength, and ultrasonic velocity, were measured. The experimental results reveal that the unit weight and thermal conductivity of the CBA concrete were highly dependent on the CBA content. The unit weight, thermal conductivity, and compressive strength of the concrete decreased as the CBA content increased. Relationships between the thermal conductivity and the unit weight, thermal conductivity and compressive strength of the CBA concrete were proposed in the form of exponential functions. The equations proposed in this study provided predictions that were in good agreement with the test results. In addition, the test results show that there was an approximately linear relationship between the thermal conductivity and ultrasonic velocity of the CBA concrete.

Sign in / Sign up

Export Citation Format

Share Document