Print ISSN: 1992-7428

Online ISSN: 2706-686X

Volume 3, Issue 6

Volume 3, Issue 6, Winter and Spring 2005, Page 1-141


High-Velocity Impact Strength of Plain and Fiber- Reinforced Polymer-Modified Concrete

Bayan S. Al-Numan .

Iraqi Journal of Civil Engineering, 2005, Volume 3, Issue 6, Pages 1-25
DOI: 10.37650/ijce.2005.172826

AbstractThis study deals with establishing high-velocity impact properties of polymer –modified concrete (PMC) including Styrene-Butadiene rubber (SBR), with different weight ratios of polymer to cement: 4%, 8% and 12%. Steel fibers were also included. Sixteen (500mm) diameter, (50mm) thick discs for high-velocity impact tests were used. In addition compressive strength, splitting tensile strength, and flexural strength (modulus of rupture) were companionly recorded. In all the tests, concrete was with and without crimped steel fibers of ratio 1% by volume.In investigating high-velocity impact strength, the decrease in projectile penetration depth was (5-17%) and the scabbing area reduced (15-35%) over reference concrete.In studying PMC including 1% by volume steel fibers, an additional increase was observed in all properties. The increases were quite significant in high-velocity impact strengths. Further reduction was recorded in scabbing area of (64-95%) and penetration depth reduced (28-39%) over control specimens. The fragmentations were reduced also. The range of corresponding compressive was (48-64)MPa ,of splitting tensile strength (4.2-7.8) MPa, and of flexural strength (5-8) MP
 

 
 

INFLUNCE OF INCREASING WATER:CEMENT RATIO ON THE SOME PROPERTIES OF CONCRETE CONTAINS LOW CONTENT OF POLYMER

Abdulkader Ismail Al-Hadithi

Iraqi Journal of Civil Engineering, 2005, Volume 3, Issue 6, Pages 26-36
DOI: 10.37650/ijce.2005.65619

1-AbstractThis research includes the variation effect of (W/C) water: cement ratio on the properties as compressive strength , flxural strength , density and workability of concrete contains low Polymer SBR ratio.1:2:4 (cement: sand :gravel) by weight mixes were used . The polymer was added as percentages of cement weight and it was 2%. Reference mix was made. Water cement ratio (w/c) were used are 0.2 , 0.3 , 0.4 , 0.5 and 0.6 respectively and 0.35 (w/c) was used for reference mix . The density of concrete varied between 2030 kg/m3 and 2360 kg/m3.

Study of Production and Some Properties of Foamed Concrete

Ibrahim A. S. Al-Jumaily; Ayad A.S. Al-Jumaily; Ameer Abdul-Rahman Al-Duleimy

Iraqi Journal of Civil Engineering, 2005, Volume 3, Issue 6, Pages 37-53
DOI: 10.37650/ijce.2005.65620

SUMMARY
This research work includes three main experimental stages. The first stage includes the production of foamed concrete. It is divided into two parts; in the first, mixing design (determination of the proportions of the raw materials) according to the required density was presented and in the second part, the mixing procedure has been illustrated.
The second stage includes preparation of samples,(i.e. molding, finishing surface, removal from molds and curing). The third stage includes several tests to estimate properties of the final product and factors influencing them . These properties include density , compressive strength , splitting tensile strength and flexural strength.
For foamed concrete with 800 kg/m3 density, the 28-day compressive strength is from (1.334 MPa) to (2.323 MPa), while with 1600 kg/m3 density, the strength is from (7.015 MPa) to (9.591 MPa).
For 1600 kg/m3 density foamed concrete, the 28-day flexural strength range is from (1.08 MPa) to (2.205 MPa).

Stress Strain Relationship of Polymer Modified No-Fine Concrete

Bayan S. Al-Numan

Iraqi Journal of Civil Engineering, 2005, Volume 3, Issue 6, Pages 54-79
DOI: 10.37650/ijce.2005.65621

Abstract
The use of no fines concrete in construction increased especially during and after 1970s. New concrete is obtained from no-fines concrete in this research by adding Styrene Butadiene Rubber (SBR) Polymer as a ratio of cement content.
This research includes the study of the effect of SBR polymer on stress-strain relationship of concrete under compression.
The concrete mixes by weight were (1:7, 1:6, 1:5, and 1:4) cement / aggregate (C/A). The polymer was added as percentages by weight of cement as (5, 7.5 and 10%). Rreference mixes were made for every case.
A new mathematical model for both ascending and descending portions is suggested in this research and discussed.
The area under the stress strain curve was found in polymer modified no-fines concrete to be greater than reference concrete and was increased with polymer / cement ratios (P/C).
The suitability of no fine polymer concrete to be used in structural members has been affirmed in this research especially for (1:4 and 1:5) C/A polymer mix.

Study the Effect of Polyethylene on Physical Properties of Asphaltic Cement

Taher M.A. Al-ani

Iraqi Journal of Civil Engineering, 2005, Volume 3, Issue 6, Pages 80-92
DOI: 10.37650/ijce.2005.65622

Abstract :-
For improving the properties of asphaltic cement several materials such as sulfur, rubber, carbon black, polymers….etc. are used for this purposes. In this study low density Polyethylene (LDPE) used at different percentage (0%, 1%, 3%, 5% and 7%) by weight of the asphaltic cement and then the changes in the properties are evaluated by pentration test (ASTM D-5), softening point test (ASTM D-2398), and Kinematics viscosity test (ASTM D-2170). Temperature susceptibility was evaluated by using Penetration vescosity number ( P.V.N ). In addition to that stiffness modulus of asphalt cement was predectied by using van der pole’s nomograph.
The study showed that the LDPE increase the hardening of asphalt cement at different percentage except at (1%), and decrease the susceptibility of asphaltic cement to temperature.

Modulus of Elasticity and Impact Resistance of Chopped Worn- Out Tires Concrete

Khalid Battal Najim

Iraqi Journal of Civil Engineering, 2005, Volume 3, Issue 6, Pages 93-111
DOI: 10.37650/ijce.2005.65623

Abstract:
This work investigates some properties of chopped worn-out tires concrete (Ch.W.T.conc.). It is a type of concrete characterized by the incorporating of Ch.W.T into the mixes as a partial replacement of volume of aggregate (sand and gravel of equal proportion). Three mixes of Ch.W.T conc. In addition to the reference mixes were selected, using Partial Replacement Ratio (PRR)of 30%, 40%, and 50%.The tests which were used in this study were: compressive strength, modulus of elasticity (static and dynamic), and impact resistance (low and high velocity). It was found that incorporating Ch.W.T in concrete effect on the properties of concrete, for example the percentage decreases in compressive strength were 41%, 46.7%, and 52.4% for concrete with 30, 40, and 50% Ch.W.T. PRR by volume of aggregate (50% sand, 50% gravel) respectively. However, it gave good indicator to be utilized as a new construction material in many applications.

Hyperbolic stress-strain parameters for non-linear Finite Element Analyses of stone column constructed in soft soil

Shlash K. T

Iraqi Journal of Civil Engineering, 2005, Volume 3, Issue 6, Pages 112-122
DOI: 10.37650/ijce.2005.65624

Abstracte:
The stress-strain behavior of any type of soil depends on a number of different factors including density, water content, structure, drainage conditions, strain conditions (i.e., plane strain, triaxial), duration of loading, stress history, confining pressure, and shear stress. In many cases it may be possible to take account of these factors by selecting soil specimens and testing conditions which simulate the corresponding field condition. Even when this can be done accurately, however, it is commonly found that the soil behavior over a wide range of stresses is nonlinear, in elastic, and dependent upon the magnitude of the confining pressure employed in the tests. In order to perform stress analysis of soils, it is desirable to employ techniques, which account for these important aspects of soil behavior.

NON-LINEAR 3D-FINITE ELEMENT ANALYSIS OF STEEL FIBER REINFORCED CONCRETE MEMEBERS SUBJECTED TO BLAST LOADING

Tariq A. Thaker; Abdulla T. Ameen

Iraqi Journal of Civil Engineering, 2005, Volume 3, Issue 6, Pages 123-141
DOI: 10.37650/ijce.2005.65625

Abstract:
This research is devoted to investigate the behavior of steel fiber reinforced concrete members subjected to blast loading. Material nonlinearity due to nonlinear response of concrete in compression, tensile cracking, strain softening after cracking, crushing of concrete and the yielding of steel reinforcement are considered.
Three-dimensional finite element is used with eight and twenty-node are hexahedral isoparametric brick element for the spatial discretization. In the idealization of the reinforced concrete structures, the steel reinforcement is incorporated in the concrete brick element as a smeared layer assuming perfect bond.
Concrete is modeled as an elasto-viscoplastic model in compression and as a linear elastic strain softening in tension. The steel reinforcement is assumed to have uniaxial properties in the direction of the bars. A classical elasto-viscoplastic model is used to model the reinforcement.
Some numerical problems are solved and compared with other studies to verify the applicability and accuracy. Parametric study to investigate the effect of some important parameters has been carried out. The results showed that the use of steel fibers in members subjected to dynamic loading lead to better performance.