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Project Risk Management Planning
Published in Davies A. Igberaese, Introduction to Project Management, 2023
On a project, there are several ways by which risk reduction may be achieved. Most of them involve taking early action before the risk occurrence rather than embarking on damage repair after the risk may have occurred. The following are typical examples of risk mitigation actions for a building project, for instance: Experimenting with prototypes before the actual installations.Conducting necessary tests, such as in test for concrete strength or sandcrete block compaction test.Selection of a more reliable supplier, e.g. for a product in respect of which there are faked imitations in the market.
Utilization of Laterite Waste in Concrete
Published in Karra Ram Chandar, B. C. Gayana, P. Shubhananda Rao, Mine Waste Utilization, 2022
B. Manjunath, Karra Ram Chandar
The compressive strength of laterite aggregate concrete is considerably lower than that of gravel or crushed granite aggregate concrete (Krishna Raju and Ramakrishnan 1972).The compressive strength increased with age up to 40% replacement; later, it decreased with an increase in the percentage replacement level of sand. The strengths of laterite concrete generally increases with age but decreases with increase in the replacement level of sand by laterite (Udoeyo et al. 2005). Compressive strength of sandcrete block decreases at a decreasing rate as percentage of laterite content increases (Ata et al. 2007). Unconfined compressive strength decreased with higher fines content. The compressive strength of the concrete samples increased as the days of hydration increased (Ogunbode and Olawuyi 2008).
Construction industry developments in Ghana
Published in Pantaleo D. Rwelamila, Abdul-Rashid Abdul-Aziz, Improving the Performance of Construction Industries for Developing Countries, 2020
Ghana has abundant natural resources like timber and earth material to make bricks. Construction of rural dwellings mainly uses these easily available materials. However, these are used in a rudimentary form with low quality standards. Processed materials such as properly seasoned timber products and burnt clay bricks are expensive compared to cement-based alternatives. The local industry is heavily reliant on sandcrete and concrete products. Established in 1952, the Building and Roads Research Institute (BRRI) is mandated to carry out research and development of local building materials and to develop construction materials from local sources (BRRI, 2020). Over the years, the institute has developed materials such as pozzolana cement, which has the potential to reduce the industry’s dependence on expensive imported cement (BRRI, 2020). The BRRI has through its work demonstrated the potential of local material to reduce construction costs, as was seen with the Kaase Timber Bridge in Kumasi, constructed using secondary timber species. The bridge, which was designed and constructed by the BRRI, cost 75% of an equivalent concrete or steel bridge (BRRI, 2020). Research from institutions such as the BRRI has not had support from the government in applying outputs to help develop cheaper, sustainable local building materials.
Investigation of the mechanical behaviour of metakaolin-based sandcrete mixtures
Published in European Journal of Environmental and Civil Engineering, 2019
Panagiotis G. Asteris, Konstantinos G. Kolovos, Adamantia Athanasopoulou, Vagelis Plevris, Gerassimos Konstantakatos
A very important material in building construction, which has been used in many developing countries, is sandcrete, mostly in the form of solid, cellular or hollow non-reinforced masonry blocks as load bearing and non-load bearing walling units (Mohammed & Cheeseman, 2011). Sandcrete belongs to a family of concretes that can be used when environmental or economic constraints limit the use of coarse aggregates. Although there is no standard definition for sandcrete, it is considered as a composite material consisting of fine aggregate (sand), ordinary Portland cement, water at an appropriate ratio and rare mineral additives (Mohammed & Cheeseman, 2011). A properly manufactured soilcrete exhibits acceptable properties for potential use in construction, such as moderate or in some cases relatively high compressive strength, low shrinkage, low thermal conductivity and high bulk density. The material can be used in the manufacture of masonry blocks and also as a binder for precast units in early stages before setting and hardening. Despite the recent advances in sandcrete technology, the use of this type of material is still limited (Denis, Attar, Breysse, & Chauvin, 2002). Kolovos, Asteris, Cotsovos, Badogiannis, & Tsivilis (2013) studied the mechanical properties of soilcrete mixtures modified with metakaolin. For the mixtures investigated, a natural clay ground soil was used as binder in moderate and low proportions in order to simulate typical mixing conditions of practice in soil stabilisation techniques. Over the last decade, a plethora of experimental (Aniculăesi, Lungu, & Stanciu, 2013; Fang et al., 2004; Omoregie & Alutu, 2006; Wenapere & Ephraim, 2009) and numerical studies (Bijan & Kaveh, 2014; Nguyen, Fatahi, & Khabbaz, 2014; Tinoco, Gomes Correia, & Cortez, 2014) have been carried out on the mechanical behaviour of cemented materials such as soilcrete and sandcrete.