EXPERIMENTAL STUDY ON THE DURABILITY TO SALINE ENVIRONMENTS OF SELF-COMPACTING CONCRETE MADE WITH COARSE AGGREGATES COMBINATION

This study focus on durability to saline environments of self-compacting concrete (SCC) made of granite-gravel combination as coarse aggregates in concrete production. In this study fine aggregates, water, superplasticizer and cement were kept constant. The percentages replacement of gravel in place of granite aggregates were 10, 20, 30, 40, and 50, while 100% granite serves as control. A total of 162 cubes of 100 100 100 mm concrete specimens were immersed over the initial curing in a water container and further cured in 5% sodium chloride (NaCl) and sodium carbonate (Na2CO3) solutions for 28, 56 and 91 days in line with ASTM C39 (2003). The tests results indicate that concrete cured in five percent (5%) of NaCl solution have compressive strength accelerating properties at early age that could not be sustained for long. While those cured in 5% of Na2CO3 solution reduced significantly the compressive strength of concret

INFLUENCE OF GRANITE-GRAVEL COMBINATION ON THE STRENGTH OF SELF-COMPACTING CONCRETE: TOWARDS A SUSTAINABLE CONSTRUCTION MATERIAL

This study focusses on the influence of granite-gravel (washed and unwashed) combination as coarse aggregate on hardened properties of Self-Compacting Concrete (SCC). Granite-gravel combination in varying percentages was used as coarse aggregates to produce SCC while other concrete constituents were kept constant. The experiments executed on hardened SCC were compressive and split tensile strength. Concrete were made using 150 mm cubes and 100 mm × 200 mm cylinders. Data obtained were analysed using graphical illustrations while Minitab was used to model values for the mix proportions. The compressive strength of SCC produced reliable results with a minimum strength of 30.96 N/mm² for 50% washed gravel at 28 days of which, the strength also increases as curing age increased. The split tensile strength of SCC increases as the curing day increased but decreased as gravel content increased with 50/50 threshold limit. The Surface plots analysis shows that the percentage increase of granite-washed gravel combination as coarse aggregate and curing ages in SCC has significant impact on compressive strength. It can be concluded that granite/gravel combination as coarse aggregates in SCC production is feasible and reliable provided the threshold limits of 50% washed gravel and 30% unwashed gravel are not exceeded

Experimental Study on the Workability of Self-Compacting Granite and Unwashed Gravel Concrete

This study deals mainly with the mix proportions using granite and unwashed gravel as coarse aggregate for self-compacting concrete (SCC) and its workability, by considering the water absorption of unwashed gravel aggregate. Mix proportions for SCC were designed with constant cement and fine aggregate while coarse aggregates content of granite-unwashed gravel combination were varied in the proportion 100%, 90%/10%, 80%/20%, 70%/30%, 60%/40%, 50% /50%, represented by SCC1, SCC2, SCC3, SCC4, SCC5 and SCC6. 100% granite (SCC1) serves as the control. The workability of the samples was quantitatively evaluated by slump flow, T500, L-box, Vfunnel and sieve segregation tests. Based on the experimental results, a detailed analysis was conducted. It was found that granite and unwashed gravel with SCC1, SCC2 and SCC3 according to EFNARC (2002) standard have good deformability, fluidity and filling ability, which all passed consistency test. SCC1, SCC2 and SCC3 have good passing ability while all mixes were in the limit prescribed by EFNARC (2002). It can be concluded that the mix design for varying graniteunwashed gravel combination for SCC presented in this study satisfy various requirements for workability hence, this can be adopted for practical concrete structures

EXPERIMENTAL AND MODELLING OF FLEXURAL STRENGTH PRODUCED FROM GRANITE-GRAVEL COMBINATION IN SELFCOMPACTING CONCRETE

The roles of coarse aggregate in concrete production cannot be over emphasized because of the volume coarse aggregate occupied in total concrete volume. The availability of locally sourced gravel aggregate (both washed and unwashed) but not put to optimal use called for this current study. The granite-gravel aggregates were varied in percentage proportions of 100/0, 90/10, 80/20, 70/30, 60/40, 50/50. A total number of 108 beams of 100×100×500 mm size were produced and cured for 28, 56 and 91 days, crushing of beams were done in line with the standard to determine the flexural strength. The MINITAB software was used to model the concrete produced. The test results indicate that 100% granite and granite-washed gravel combination up to 30% behaves satisfactorily in the reinforced concrete structure using self-compacting concrete while 40 and 50% for washed gravel showed a bit of satisfactions. Similar trend was observed for unwashed gravel of which flexural strength of the beam is still reliable at 40% unwashed gravel

Abnormalities of the external genitalia and groins among primary school boys in Bida, Nigeria

Background: Abnormalities of the male external genitalia and groin, a set of lesions which may be congenital or acquired, are rather obscured to many kids and their parents and Nigerian health care system has no formal program to detect them.Objectives: To identify and determine the prevalence of abnormalities of external genitalia and groin among primary school boys in Bida, Nigeria.Methods: This was a cross-sectional study of primary school male pupils in Bida. A detailed clinical examination of the external genitalia and groin was performed on them.Results: Abnormalities were detected in 240 (36.20%) of the 663 boys, with 35 (5.28%) having more than one abnormality. The three most prevalent abnormalities were penile chordee (37, 5.58%), excessive removal of penile skin (37, 5.58%) and retractile testis (34, 5.13%). The prevalence of complications of circumcision was 15.40% and included excessive residual foreskin, excessive removal of skin, skin bridges and meatal stenosis. Undescended testes were seen in 6 (0.90%) boys, with median age of 9 years and 2 were bilateral. Also, micropenis was detected in 27 (4.07%) of the pupils.Conclusion: Inguino-penoscrotal abnormalities are common in our community (36.20%). Screening of pre-school and school children to  detect them should be introduced into the school health programs in Nigeria.Keywords: External genitalia, groin abnormalities, boy

PHYSICAL AND MECHANICAL PROPERTIES OF CONCRETE MADE WITH LOCAL GRAVEL FOR SUSTAINABLE CONSTRUCTION: CASE STUDY OGUN AND OYO STATES, NIGERIA

The study focus on assessment of normal concrete made with gravel obtained from Ogun and Oyo States, Nigeria. In this vein, gravel types from four commonly used mining pits namely: Iyana Abib, Sabo, Alamutu and Igbo-Ora were considered. The method of study was purely experimental. The conventional mix ratios used were 1:2:4 and 1:3:6. The grading of fine and coarse aggregates were determined using sieve analysis, while the tests performed on fresh concrete were slump and compaction factor. Compressive strength test was executed on the hardened concrete. Concretes were made using 150 mm concrete cubes. The concrete was tested on the 3, 7, 14, 21 and 28 days. The average compressive strength obtained for 1:2:4 mix ratio were 25.3 N/mm2 (gravel from Igbo-Ora), 23.7 N/mm2 (gravel from Alamutu), 19.7 N/mm2 (gravel from Sabo) and 13.5 N/mm2 (gravel from Iyana-Abib). Also, the average compressive strength on the 28 days obtained for 1:3:6 mix ratio were 20.5 N/mm2 (gravel from Igbo-Ora), 19.5 N/mm2 (gravel from Alamutu), 15.4 N/mm2 (gravel from Sabo) and 9.9 N/mm2 (gravel from Iyana-Abib). Minimum requirement of 20 N/mm2 by BS 8110:1997 and ACI 318:2008 for 1:2:4 mix ratio was satisfied by gravel from Igbo-Ora and Alamutu. Also gravel from Igbo-Ora, Alamutu and Sabo satisfied 15 N/mm2 minimum requirement by BS 8110:1997 and ACI 318:2008 for 1:3:6 mix ratio. It was concluded that gravel from Igbo-Ora produced the highest strength for both 1:2:4 and 1:3:6 mix ratio and is recommended for construction work where granite is not available or uneconomical

In vitro Anticancer Screening of 24 Locally Used Nigerian Medicinal Plants

Background: Plants that are used as traditional medicine represent a relevant pool for selecting plant candidates that may have anticancer properties. In this study, the ethnomedicinal approach was used to select several medicinal plants native to Nigeria, on the basis of their local or traditional uses. The collected plants were then evaluated for cytoxicity. Methods: The antitumor activity of methanolic extracts obtained from 24 of the selected plants, were evaluated in vitro on five human cancer cell lines. Results: Results obtained from the plants screened indicate that 18 plant extracts of folk medicine exhibited promising cytotoxic activity against human carcinoma cell lines. Erythrophleum suaveolens (Guill. & Perr.) Brenan was found to demonstrate potent anti-cancer activity in this study exhibiting IC50 = 0.2-1.3 $\mu$g/ml. Conclusions: Based on the significantly potent activity of some plants extracts reported here, further studies aimed at mechanism elucidation and bio-guided isolation of active anticancer compounds is currently underway.Chemistry and Chemical Biolog