Engineering and Technology Journal

Direct Shear Behavior of Carbon Fiber Reinforced Self- Compacting Concrete

Kaiss F. Sarsam; Tareq S. Al-Attar; Ghzwan Ghanim Jumah

Volume 32, Issue 10 , October 2014, , Page 2491-2513

https://doi.org/10.30684/etj.32.10A.13

Abstract

This paperrepresents an experimental and statistical investigation for the behavior of connectionpoints produced by using self-compacting concrete and subjected to direct shear. The ... Read More ... This paperrepresents an experimental and statistical investigation for the behavior of connectionpoints produced by using self-compacting concrete and subjected to direct shear. The investigation also includes the effect of carbon fiber inclusion as reinforcement on self-compacting concrete (SCC) behavior in direct shear. This study gives results of sixteen push-off or direct shear specimens in four groups. Variations include volume fraction for carbon fiber (V_f= 0.00, 0.50, 0.75 and 1.00) % for every percentage change in the steel reinforcement. The steel reinforcement parameter ρ_vf f_y values are (0.00, 2.66, 5.33 and 7.99) MPa(where ρ_vf varies from 0.00 to 0.0173 and f_y=585.7MPa) . The main material properties studied include compressive strength, splitting tensile strength and modulus of rupture. Measurements of deformations were made throughout testing of shear specimens. The dimension of the shear plane in the push-off specimenswas 170x185 mm. The shear reinforcement was normal to the shear plane. Specimens were cast by using SCC which is a type of high performance concreteand reinforced with carbon fiber. This work aims to investigate the direct shear behavior of SCC with or without carbon fiber at constant water to cementitious materials ratio of 0.3 by weight. It is found that using carbon fiber increased the direct shear strength. However, carbon fiber alone (without reinforcement) leads to brittle failure. In contrast, adding rebars leads to higher strain and more ductile behavior-increased shear capacity is obtained when higher steel quantity is used. The aim of adding carbon fibers was the increase of the horizontal strain (displacement). It was found that the optimum percentage of volume fraction was 0.75 % for fresh and hardened concrete. In addition, the effects of carbon fiber on compressive strength of SCC lead to a drop in compressive strength (f_c^') compared with reference specimens. This drop in f_c^' was 2.39, 8.38 and 13.58% for V_f=0.50, 0.75 and 1.00%, respectively. In contrast, the splitting tensile strength increased by 3.34, 31.2 and 18.2 as compared with the cylinder strength without carbon fibers atV_f equal to0.50, 0.75 and 1.00% respectively. The modulus of rupture increased by [11.9, 21.99 and 13.83%] as compared with SCC without carbon fibers at〖 V〗_f equal to 0.50, 0.75 and 1.00% respectively. Based on push-off tests results for this work and those available in the literature, two statisticalmodels have been established using regression analysis. Four variables f_c^',f_ct,ρ_vf f_y and V_f, were included in these models. Both models showed good representation according to their coefficients of variation (COV)values. Verification of the models were done by using 273 observations from literature and the present work.

Assessing and Evaluating the Effect of Organic Matters on Clayey and Silty Soil Stiffness Properties

Aqeel Al Adilil; Kawther Y.H. Al-Soudany

Volume 31, Issue 19 , November 2013, , Page 103-119

https://doi.org/10.30684/etj.31.19A.8

Abstract

Construction of building and other civil engineering structures on weak or soft soil is highly risky because such soil is susceptible to differential settlements, poor shear strength, ... Read More ...

Predicting the Strength of Fiber Reinforced High Performance Concrete Based on Push-Off Tests

Maha M.S. Ridha; Nagham T. Hamad; Kaiss F. Sarsam

Volume 30, Issue 7 , April 2012, , Page 1187-1202

https://doi.org/10.30684/etj.30.7.7

Abstract

This paper reports the results of an investigation into the strength of fiber reinforced high-performance concrete (FRHPC)based on push-off tests. Both experimental and analytical studies ... Read More ...

Keywords = Direct Shear

Direct Shear Behavior of Carbon Fiber Reinforced Self- Compacting Concrete

Abstract

Assessing and Evaluating the Effect of Organic Matters on Clayey and Silty Soil Stiffness Properties

Abstract

Predicting the Strength of Fiber Reinforced High Performance Concrete Based on Push-Off Tests

Abstract