Flexural performance of textile fine grained mortar containing risk husk ash as a partial cement replacement in reinforced concrete beams

External strengthening of RC beam become a popular method to reduce deterioration. Due to highest demanding on external strengthening, a new innovation was introduced called as textile fine grained mortar (TFGM). TFGM is a composite material which is combined fine grained mortar (FGM) that utilized rice husk ash (RHA) as a partial cement replacement material of FGM and textile reinforcement made from glass fibre reinforcement called as alkali resistant (AR) glass. Characteristic of the binder were firstly performed by conducting X Ray Fluorescence, X Ray Diffraction, particle size distribution and surface morphology. From characterization of RHA, it is categorized as a pozzolanic material from chemical composition, amorphous form of RHA and fineness of RHA. FGM with different percentage of RHA replacement varies from 0 %, 10%, 20 %, 30 % and 40% was investigated under compressive and flexural strength. Optimum replacement of RHA in FGM also determined. 20 % of RHA replacement in cement consumption of FGM gave excellent of compressive and flexural strength. Utilization of 20 % RHA in FGM was continuing to use when FGM combined with AR glass as textile reinforcement and produced new composite material TFGM. Several layers of TFGM were selected in this study, namely 2 layers, 4 layers, 6 layers and 8 layers. Flexural strength was conducted to determine the prism increment in flexural when externally bonded with TFGM. After flexural prism were done, 4 layers and 8 layers of TFGM were selected as desired layer to be applied on RC beams. Flexural test was perform on RC beams and resulted 4 layers of TFGM shown highest in flexural compared to control RC beams. But, 8 layers of TFGM were resulted failed due to delamination at the end of TFGM. As a conclusion, TFGM were very excellent in strengthening of RC beams. RHA is a highly promising in increments of flexural strength and AR glass also reduced the deflection of RC beams

Physicochemical characterization and antimicrobial properties of rhamnolipids produced by Pseudomonas aeruginosa 47T2 NCBIM 40044

7 pages, 2 figures, 3 tables.-- PMID: 12474254 [PubMed].-- Available online Dec 3, 2002.Pseudomonas aeruginosa 47T2, grown in submerged culture with waste frying oil as a carbon source, produced a mixture of rhamnolipids with surface activity. Up to 11 rhamnolipid homologs (Rha-Rha-C8-C10; Rha-C10-C8/Rha-C8-C10;Rha-Rha-C8-C12:1; Rha-Rha-C10-C10; Rha-Rha-C10-C12:1; Rha-C10-C10; Rha-Rha-C10-C12/Rha-Rha-C12-C10; Rha-C10-C12:1/Rha-C12:1-C10; Rha-Rha-C12:1-C12; Rha-Rha-C10-C14:1; Rha-C10-C12/Rha-C12-C10) were isolated from cultures of P. aeruginosa 47T2 from waste frying oil and identified by HPLC-MS analysis. This article deals with the production, isolation, and chemical characterization of the rhamnolipid mixture RL47T2. The physicochemical and biological properties of RL47T2 as a new product were also studied. Its surface tension decreased to 32.8 mN/m; and the interfacial tension against kerosene to 1 mN/m. The critical micellar concentration for RL47T2 was 108.8 mg/mL. The product showed excellent antimicrobial properties. Antimicrobial activity was evaluated according to the minimum inhibitory concentration (MIC), the lowest concentration of an antimicrobial agent that inhibits development of visible microbial growth. Low MIC values were found for bacteria Serratia marcescens (4 g/mL), Enterobacter aerogenes (8 g/mL), Klebsiella pneumoniae (0.5 g/mL), Staphylococcus aureus and Staphylococcus epidermidis (32 g/mL), Bacillus subtilis (16 g/mL), and phytopathogenic fungal species: Chaetonium globosum (64 g/mL), Penicillium funiculosum (16 g/mL), Gliocadium virens (32 g/mL) and Fusarium solani (75 g/mL).Finnancial support by the CIRIT and CICYT; Grant Number: 199956R 00024, PPQ-2000-0105-P4-03, REN 2001-3224.Peer reviewe

A Study on Ordinary Portland Cement Blended with Rice Husk Ash and Metakaolin

Abstract. This paper tries to investigate the effect of replacing Ordinary Portland cement (OPC) with Metakaolin (MK) and Rice husk ash (RHA) on the physicomechanical properties such as consistency, setting times, soundness and mortar compressive strength of ternary cement up to 40 % cement replacement. The soundness of the blended cement pastes and compressive strength of the blended mortars were conducted using Le Chatelier apparatus and Tonic Technic compression machine while the initial and final setting times were conducted on the blended cement paste using Vicat apparatus. Nineteen ternary cement mortars were prepared to comprise of OPC, RHA MK at different proportions and tested at 2, 7, 28 and 60 days. Results indicated that as RHA was gradually increased up to 25% at constant MK content, the volume expansion of the ternary cement paste increased gradually. On the other hand, as MK was increased from 5-25% at constant RHA, the volume expansion diminished. The water consistency of ternary cement paste experienced a variation as MK was increased up to 25 wt% at constant RHA up to 10 wt%. However, at 10 wt% constant RHA as MK was increased the water demand gradually increased. Similarly, an increase in RHA at constant MK increased the water demands of the ternary blends. An increase in RHA from 5-25 wt% at 5-25 wt% constant MK resulted in an acceleration in the initial and final setting times of cement blends. These accelerations could be attributed to the pozzolanic activity leading in shorter setting time. Whereas a series of accelerations and retardations of both setting times were experienced as the MK was increased from 5-25 wt% at 5-25 wt% constant RHA. It was observed that increment in the MK or RHA up to 10 wt% at constant RHA/MK up to 10 wt% resulted in improved mortar compressive strength of the ternary blend in comparison with control. This improvement was attributed to the high silica/alumina contribution to the matrix by MK inclusion, the C/S ratio in the cement matrix and RHA pozzolanic reactivity despite its unburnt carbon. All mortar compressive strength of the cement blends and control experienced an increase as the curing days were lengthened from 2 to 60 days. The enhanced strength compared with the control especially beyond 28 days could be attributed to the slow pozzolanic reaction resulting from the formation of additional CSH and CAH from the interaction of the residual CH and the silica available in the MK and RHA. The best compressive strength at 60 days was obtained at cement replaced with 15 wt% and 20 wt% at MK 5 wt% RHA producing a mortar compressive strength of 40.5 MPa

The influence of rice husk ash addition on the properties of metakaolin-based geopolymers

This paper investigates the replacement of metakaolin (MK) with rice husk ash (RHA) in the production of alkali-activated binders or geopolymers. The influence of the RHA addition on compressive and flexural strength, as well as water absorption and apparent porosity were determined, in terms of the percentage of RHA in the mixture and molar ratios of the mixes. Fourier Transform Infrared (FTIR) spectroscopy and Energy Dispersive spectroscopy (EDS) were carried out to assess the changes in the microstructure of the geopolymer matrices with the RHA addition. Results have shown that RHA may be a supplementary precursor for geopolymers. The composition of the geopolymer matrices containing 0-40% RHA is very similar, which indicates that the additional Si provided by RHA is not incorporated to the geopolymer matrix. In addition, geopolymers with RHA content higher than 40% present a plastic behavior, characterized by extremely low strength and high deformation, which can be attributed to the formation of silica gel in formulations containing variable Si/Al ratio

The management of an accessory or replaced right hepatic artery during multiorgan retrieval:results of an angiographic study

In the presence of anatomical variants such as an accessory or replaced (A/R) right hepatic artery (RHA), a conflict of interest can arise during organ retrieval between liver and pancreatic teams. This angiographic study examines the anatomy of the inferior pancreaticoduodenal artery (IPDA), its relation to the A/R RHA, and the implications for the use of livers and pancreases from multiorgan donors. Gastrointestinal angiograms performed in our institution for unrelated indications were reviewed, and the relevant arteries, their diameters, the distances between origins, the time at which variants were found, and the blood supply to relevant solid organs were recorded. A review of 122 angiograms identified 100 patients in whom both the superior mesenteric artery (SMA) and the celiac axis were cannulated synchronously; these patients composed our study cohort. The IPDA was identified in 95% of the cases. There were 8 patients with a replaced RHA and 4 with an accessory RHA. In all 12, the IPDA had an SMA origin; 3 of these shared a common origin with the A/R RHA on the SMA. In the rest, the mean distance between them was 29 mm (range = 17.8-48.3 mm). All anomalous arteries found were segmental vessels. In conclusion, the A/R RHA incidence in our series was 12%, and no case had an IPDA originating from the A/R RHA. Separate accessory RHA and IPDA origins potentially allow an uncompromised accessory RHA (with its Carrel patch) without risk of prejudice to the pancreatic graft if retrieval is accurately performed. Rarely (3%), there is a common origin between the A/R RHA and the IPDA, and back-bench reconstruction would be required to allow the use of both the liver and pancreas

Relationship between Ultrasonic Pulse Velocity and Compressive Strength of Self Compacting Concrete incorporate Rice Husk Ash and Metakaolin

The objective of the present investigation was to evaluate RHA and MK as supplementary cementitious materials (in both binary and ternary systems) in terms of harden properties in blended cement SCC and to identify the optimal level of replacement of ordinary Portland cement (OPC) with RHA, MK, or RHA+MK. The blended cements were prepared by replacing OPC with RHA, MK, or RHA+MK (5ndash40%) in dry conditions. In addition to that the interrelationship between harden properties such as compressive strength and ultrasonic pulse velocity was discussed

Pemanfaatan Abu Sekam Padi Dengan Treatment Hcl Sebagai Pengganti Semen Dalam Pembuatan Beton

Beton pozzolanic merupakan beton dengan penambahan material pozzolan yang bertujuan untuk mengurangi penggunaan semen dalam campuran beton. Penelitian ini berfokus pada pengaruh penggunaan material pozzolan berupa Rice Husk Ash (RHA) terhadap workability dan kuat tekan dari beton. Persentase penggunaan RHA yang digunakan adalah 5%, 10%, dan 15%. Dilakukan empat jenis treatment yang berbeda pada RHA antara lain penumbukan, penambahan alkali treatment (HCl), pembakaran dengan suhu 600°C, serta penambahan alkali treatment (HCl) pada RHA yang telah dibakar dengan suhu 600°C. Analisa terhadap RHA yang dibakar dengan suhu 600°C dilakukan dengan pengujian X-Ray Fluorescence (XRF). Hasil tes menunjukkan bahwa RHA yang digunakan merupakan pozzolan tipe C dengan total SiO2+ Fe2O3 + Al2O3 sebesar 83.82%. Dilakukan pengujian kuat tekan pada tiga sampel beton kubus berukuran 15x15x15 cm³ pada saat umur beton mencapai 7, 14, 28, dan 56 hari. Hasil menunjukkan bahwa beton dengan campuran RHA memiliki workability yang lebih rendah dibandingkan dengan beton kontrol. Uji kuat tekan beton dengan penambahan abu sekam mencapai 30.56 MPa selisih 7.1 % dari kuat tekan beton kontrol (32.89 MPa)

Characterization and pore structure of rice husk ash cementitious material

An Investigation on the mineralogical and chemical characterization, pore structure, chemical shrinkage and pozzolanic activity of commercially produced rice husk ashes (RHA 1 and 2) and a control silica fume (SF) are presented in this paper. RHA possesses high silica content like silica fume which is used as supplementary cementitious materials (SCM) in the production of concrete. There is a need for an alternative to silica fume in the production of concrete because of its high demand and relatively high cost. The mineralogical composition of RHA 1 and 2 show high silica content of 77% and 84% respectively which is close to the silica content (˃80%) of class 2 silica fume. The oxides of Ca are 3.53% and 7.68% while Al is 1.19% and 1.29% for RHA 1 and 2 respectively which suggest that RHA is a low Ca+2 content binder. The results of chemical shrinkage of RHA 1, 2 and SF are 0.42 mL/g, 0.52 mL/g and 0.11 mL/g after 500 hrs of hydration. This indicates that RHA 2 has the highest reactivity (hydration) with water due to its highest Ca+2 content

Kuat Tekan dan Ultasonic Pulse Velocity (UPV) Beton OPC dan OPC Abu Sekam Padi untuk Aplikasi di Lingkungan Gambut

This research study the compressive strength and ultrasonic pulse velocity (UPV) of OPC and OPC rice husk ash (RHA) concrete. Test will be measured after 28 days immersed in peat water. Specimens will be immersed in peat water after 28 days cured in normal water. Compressive strength of OPC concrete showed biggest value than OPC with admixture RHA 5% and 10% which is increasing amount of RHA for subsitute cement will decreasing compressive strength. Test UPV of the specimen showed OPC RHA 5% being best quality than other