Putra Jaya Ramadhansyah

Compressive and flexural strength of foamed concrete containing polyolefin fibers

Foam concrete is a lightweight concrete which is produced relatively inexpensively. However, due to its low strength and brittleness the application in building construction is rather limited. A study has been undertaken to investigate the effects of polyolefin fibers at a relatively low volume fraction (0 %, 0.2 %, 0.4 % and 0.6 %) on the compressive and flexural properties of foamed concrete. The foamed concrete was designed to achieve a target strength of 8-10 MPa with a density of 1600 kg/m3 at the age of 28 days. For each mixture, nine 100x100x100 mm cubes and three 100x100x500 mm beam were prepared. The compressive test was performed on cubes and three points loading flexural test on the beams was carried out in accordance to MS 26:Part 2:1991. Test results showed that polyolefin fibers only slightly improved the compressive strength and flexural strength of foamed concrete by 4.3% and 9.3% respectively.

Mechanical properties of double layer rubberized concrete paving blocks

This paper sought to evaluate the influences of different levels of waste rubber tyre (rubber granules) as an aggregate replacement in the production of double layer concrete paving blocks (CPBs). Waste rubber tyres were used as an aggregate replacement at the levels of 0%, 10%, 20%, 30%, and 40%. The characteristics of the double layer rubberized CPB were examined via a series of tests. According to the results, the density, porosity, and compressive strength of the double layer rubberized CPB is highly influenced by the percentage of rubber content. The compressive strength test has proven that by using rubber granules as an aggregate, the compressive strength is able to be manipulated. As the percentage of rubber granules increase, the compressive strength will decrease as the amount of solid, load-carrying material reduces. Compressive strength was at its peak when the rubber content was at 10%. 1-4 mm rubber granules were used as a replacement of fine aggregate and 5-8 mm rubber granules as coarse aggregate; both at the level of 40%. As a result, a double layer rubberized CPB with 28-days compressive strength of maximum 28 MPa is produced.

Double Layer Concrete Paving Blocks Using Waste Tyre Rubber as Aggregate Replacement

This study provided the test results on the mechanical properties of double layer concrete paving blocks (CPBs) obtained by replacing portions of the conventional aggregate with waste tyre rubber. The mechanical properties discussed in this paper were compressive and flexural strength. Results indicated that the density of double layer CPBs containing rubber was lower than that of conventional CPB. The decrease was found to be proportional with the waste tyre rubber content. Due to the low strength and stiffness of waste tyre rubber particle, the compressive and flexural strength of double layer CPBs containing rubber appeared to be lower than that of conventional CPB.

Effect of Coarse Aggregate Sizes on Properties of Porous Concrete Paving Blocks

Properties of Porous Concrete Paving Blocks (PCPB) were investigated in this study. Two groups of coarse aggregate sizes were performed; passing 8 mm retains 5 mm and passing 10 mm retains 8 mm. For mixture design, 100 % of coarse aggregate were used. However, fine aggregate was eliminated in this investigation. The density, water absorption, flakiness index and elongation index test were performed to determine the properties of the coarse aggregate used in this study. Compression test and skid resistance test were used to evaluate the performance of PCPB. The results show that PCPB containing coarse aggregate size 5 8 mm give high compressive strength compared to others PCPB specimen. In addition, both PCPB specimens give an in increasing in skid resistance approximately 30 % compared to Concrete Paving Blocks (CPB).

Performance of RHA Blended Cement Concrete under Sodium Chloride via Wetting and Drying

This paper investigates the effects of concrete containing RHA subjected to sodium chloride solution (5% NaCl) under wetting and drying cycles. Five levels of cement replacement (0%, 10%, 20%, 30% and 40% by weight) were used. The total cementitious content used was 420 kg/m3. A water/binder ratio of 0.49 was used to produce concrete having target strength of 40 MPa at the age of 28 days. The performance of blended cement concrete was evaluated using compressive strength, chloride ion-penetration and chloride penetration depths. The results showed that the RHA blended cement concrete performed better than Portland cement concrete when exposed to 5% sodium chloride solution via cyclic wetting and drying conditions. RHA can reasonably be used as a cement replacement material for the purpose of reducing the chloride ion-permeability of the concrete, which in turn will increase its durability. Generally, a RHA replacement level of 10% or 20% is sufficient to enhance resistance to sodium chloride.

A Review of Porous Concrete Pavement: Applications and Engineering Properties

Porous concrete technology has been used since 1970s in various parts of the United State as an option to complex drainage systems and water retention areas.Porous concrete pavements have become popular as an effective stormwater management device to control the stormwater runoff in pavement. The objective of this paper is to study a pre-review on Porous concrete pavement and it previous laboratory study. From the literature, it was found that, the strength of the porous concrete pavementstill need to improve. To improve the strength of the porous concrete, various additive have been study as a part of porous concrete mix and yetthe optimum condition to produce good porous concrete still not been established. From the previous study, it was found that to prepare the porous concrete laboratory specimen, the use of standard Proctor hammer (2.5kg) and Pneumatic press (70 kPa compaction effort) resulted in the closest properties to the field porous concrete.

Effect of Rice Husk Ash Fineness on the Properties of Concrete

In the present research, the effect of rice husk ash fineness on the properties of concrete was studied. Eight different fineness grades of rice husk ash were examined. A rice husk ash dosage of 15% by weight of binder was used throughout the experiments. The water-to-binder ratio was 0.49 to produce concrete having target strength of 40MPa at 28 d. Workability, compressive strength and gas permeability tests were carried out to identify the properties of concrete. The results revealed that increasing the fineness of RHA by mechanical grinding was found to improve the workability of RHA blended cement concrete. In addition, the use of RHA3 with mean particle size of 9.52μm produces the concrete with good strength. Finally, significant improvement was observed in mixtures incorporating RHA in terms of permeability coefficient.

Effects of Kaolin Clay on the Mechanical Properties of Asphaltic Concrete AC14

This study investigated the effect of kaolin clay on the mechanical properties of asphaltic concrete AC14 through Marshall Stability, resilient modulus, and dynamic creep tests. Four replacement levels of kaolin clay (2%, 4%, 6%, and 8% by weight of the binder) were considered. Kaolin clay functioned as an effective filler replacement material to increase the mechanical properties of asphalt mixtures. Asphaltic concrete with 2% to 4% kaolin clay replacement level exhibited excellent performance with good stability, resilient modulus, and creep stiffness.

Strength and properties of concrete pavement incorporating multiple blended binders

This study investigated the effects of multiple blended binders on the properties and performance of concrete pavement. Mineral admixtures, namely, silica fume, metakaolin, and rice husk ash, are used to replace ordinary Portland cement at replacement levels of 0% (control mix), 5%, 10%, and 15% by mass-to-mass basis. The performance of the multiple binders on the concrete pavement properties was evaluated based on compressive strength, strength reduction, and strength activity index. Results showed that the mineral admixtures can be satisfactorily used as cement replacement materials to increase the properties of pavement concrete. Moreover, concrete pavements with 5% and 10% replacement levels exhibited excellent performance with good strength.

Performance of macro-clay on the porous asphalt mixture properties

This paper present and discusses influence of macro-clay on the physical and rheological properties of porous asphalt mixture. Various percentage of macro-clay (starting from 2% to 8%) was blended in an asphalt binder and compacted using the Marshall compactor. The blended asphalt was characterized using penetration, softening point test and penetration index compared with unmodified binder. Performance tests of asphalt mixture were carried out such as Los Angeles Abrasion Value (LAAV) and stability and flow test in order to determine the strength and durability. The results show that the addition of macro-clay would increase in softening point but decrease in binder penetration. Based on the results, while macro-clay changes physical and rheological properties of bitumen and increase stiffness, it also improves strength and durability resistance, as well. Generally, the best improvements in the modified binders were obtained with 4% of macro-clay.