Authors:
Odaudu Ugbede Sunday; Abdullahi Aminu Lawan Pages: 32 - 37 Abstract: Fire outbreaks in market places are frequently occurring in Nigeria; they have different negative effects such as the destruction of valuable goods, properties and the loss of lives of people. Thus, market environments in the Federal Capital Territory of Nigeria were studied with the aim of determining the passive fire readiness, in order to provide improved design guidelines for Nigerian market design against fire outbreaks. Descriptive survey method was used for this research. There are 1,430 total number of sales points in the study area. Out of the total number of sales points, 287 sales points were studied by the use of systematic sampling method at every 5th interval. Data were obtained from the core stakeholders such as the Federal Fire Service of Nigeria, National Association of Nigerian Traders and the managing company of the market through interviews. They were also obtained from the direct observation schedule, and from the sales people in the market via focus group discussions. Contents analysis technique was used to analyze the data; the result of the data analysis was accepted via normality test. In the presence of other findings is inadequate fire exit gates in the market. Among other guidelines is that all markets must have adequate number of fire exit gates and these should be determined by the architects with respect to the size of markets in terms of the number of available facilities and expected human population. PubDate: 2023-04-05 DOI: 10.12691/ajcea-11-2-1 Issue No:Vol. 11, No. 2 (2023)
Authors:
Mansoor Sabzali; Lloyd Pilgrim Pages: 38 - 44 Abstract: Refraction is always a major problem for the near-ground geodetic measurements. Thus far, there have been numerous studies showing the influences of atmosphere on the refracted ray leading to the variation in the distance and direction measurements. The refraction is projected into two non-correlated components on horizontal and vertical planes called horizontal and vertical refraction, respectively. Both impact the measurements in their corresponding directions. It is noted that, in terms of magnitude, the refracted zenith angle, in vertical plane, has always been assumed to be far larger than refracted horizontal angles (i.e., refracted horizontal angle is imagined to be minor or negligible). There are considerable productive understandings of vertical refraction influencing the vertical/zenith direction in the literatures. However, the limitation in determination of the horizontal (side or lateral) refraction is still a debatable issue. The research aimed to reveal the broader comprehension of the horizontally refracted ray affecting horizontal angle measurements. The presented model embraces the relationship between the zenith angle and refracted horizontal angle, which could be the desirable technique to computation of refracted horizontal angle at each zenith angle (i.e., ideally, it can be employed in the case of terrestrial laser scanning due to the change of zenith angle for every individual measured point). Thus, the dependency between vertical and horizontal refraction will be obvious. PubDate: 2023-04-26 DOI: 10.12691/ajcea-11-2-2 Issue No:Vol. 11, No. 2 (2023)
Authors:
Rupesh Surwade; Mohammad Arif Kamal Pages: 45 - 51 Abstract: The conventional brick walls, stone walls and even hollow concrete blocks require mortar to hold the individual building units in desired position. A new concept of concrete block construction without mortar has been developed, but due to lack of proper promotion and lack of confidence as to their structural stability, they have not been largely used in India. Many such ideas of different type and shape of blocks for jointing without cement or mortar have been developed and used in many countries. The basic theory behind elimination of mortar is to devise an interlocking system of blocks which are technically sound, structurally safe for vertical and wind loads. Interlocking in wall masonry is very unique and one such Technology is known as Hydraform Interlocking Building system that replaces the conventional brick and mortar by using Hydraform machine made interlocking blocks. Besides the cost of mortar itself the time spent in making and placing mortar can be reduced to lay up the blocks. This paper examines the case of Hydraform interlocking blocks as a building material and discusses the engineering viability and properties of such interlocking blocks in masonry construction. The paper concludes that Hydraform interlocking blocks are a viable alternative to conventional bricks with more intangible benefits attached to them. PubDate: 2023-05-21 DOI: 10.12691/ajcea-11-2-3 Issue No:Vol. 11, No. 2 (2023)
Authors:
Sorel Gael Dzaba Dzoualou; Louis Ahouet, Sylvain Ndinga Okina, Mang Egrik P. W. O. Nkembo Pages: 52 - 63 Abstract: This work evaluates the effect of adding limestone (corrector) to lateritic gravelly on the granulometric fractions of the mixtures in the process of modifying the mechanical properties. The lateritic gravelly - limestone couple does not obey the law of mixtures. The optimal mixture is obtained by adding 30 % by weight of the corrector to obtain a mixture with unmeasurable clay, silt (4.25 %) and sand (19.47 %) contents. The results obtained show that from 15-30% by weight of the corrector, the compressive strength, elastic modulus, CBR and maximum dry density increase and the use properties are improved. From 30-40% by weight of the corrector with sand fraction SF (19.47-21.09%) in the mixture, the mechanical properties decrease. The addition of the corrector (15-40%) decreases the clay (5.18-1.68%) and silt (14.09-0.67) fractions, while the sand fraction (12.93-21.09%) increases by 63.11%. The increase of the sand fraction by 50.58% decreases the plasticity index by 77.16%. For a sand fraction SF (50.58-63.11%), the plasticity index is not measurable and the sand equivalent SE (32.5-35%) of the mixture increases by 7.69%. Increasing the sand fraction causes the compaction curves (Proctor) to flatten and the optimum moisture content to decrease. There is a negative correlation between compressive strength and strain at failure. Mixes containing 15-25% and 30-40% of the corrector can be used as a base layer for T1 < (5.105) and T1-T2 (5.105 - 1.5.106) traffic respectively, in terms of the cumulative number of passes of a 13T equivalent axle. PubDate: 2023-05-21 DOI: 10.12691/ajcea-11-2-4 Issue No:Vol. 11, No. 2 (2023)
Open Access journal
