Evaluation Of Effectiveness Of Strawbale As A Building Material

Fawale, Babatunde Lawale
Ajayi, Johnson Oluwafemi
Oyedemi, Peter Oluwatosin

This project is an evaluation of the effectiveness of strawbale in building construction. It introduced the use of straw, which when baled could be used as a resource, that is, as a walling material, more economically than other conventional walling materials.

This study shows the edges that strawbale has over other conventional walling materials (sandcrete block), thermal insulating property, availability ease of construction, economical amongst others. The minimum plaster thickness (coating) which when applied to the strawbale wall that can give the optimum strength was found to be 15mm this is obtained from compressive strength test.

It also displays the graphical representation of the thermal insulation tests carried out on the two prototype buildings (strawbale and sandcrete block), in which strawbale building retained more heat than the sandcrete block building.
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Study The Contribution In The Additions Mineral On The Paste, Mortar And Their Impact On Total Porsity

Guimer Tarek and Mellas Mekki
Department of Civil Engineering, Mohamed Khider University, Biskra, BP 145, Biskra 07000, Algeria
Tel fax: 033 73 45 28

This work aims to study the evolution of the resistance of Portland cement pastes and mortars containing two mineral additions such as calcareous filler and finely crushed slag.

The effects of the addition of two mineral additions to Portland cement pastes are mortars, has been carried to evaluate the evolution of the mechanical resistance as function of the age and the mode of the treatment .This study is a simplified approach to show the contribution of the mineral addition on the development of the mechanical resistance, and the porosity obtained using methanol exchange method. In addition, to confirm this study and based on laboratory test resorts approximate equations were obtained

Keywords: Porosities, cement paste, mortar, mechanical resistance, exchange by methanol.
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Socio Economic Impact Of Failure Of Transmission Line Tower Foundations

A report by Christian Johnson and Thirugnanam

Transmission line towers are constructed for power evacuation purpose from generating stations to various load centers. Though they are considered to be the most stable and versatile semi-permanent structure, often they collapse due to failure of foundations, disrupting transfer of large blocks of power affecting the society to a larger extent. A brief review of literature on failure of transmission line tower foundations have been made and Case study involving data collection and visual inspection of transmission line tower foundation apart from diagnosis of transmission line tower stubs and laboratory experimentations have been presented. Based on the literature review and the case study undertaken as a part of the research, three predominant causes leading to failure of transmission line tower foundations have been discussed. Socio – economic impact of failure of transmission line tower foundations have been discussed. Remedial measures found through the research study for preventing failure of transmission line tower foundations have been briefly outlined.

Corrosion, Foundations, Failure, socio- economic, transmission line tower
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Bridge Deck Analysis By Finite Difference Method

A detailed analysis done by Gautam Chattopadhyay

Names and Symbols used:
Ardeck – area of the deck.
wdeck – width of deck.
span – span length of bridge.
izlong – Moment of inertia of each longitudinal girder about z axis (transverse axis)
iztrans – Moment of inertia of entire deck in transverse direction about longitudinal axis.
flexkl – Flexural rigidity in longitudinal direction.
flexkt – Flexural rigidity in transverse direction.
ngird – number of longitudinal girders.
tslong – Tosional rigidity in longitudinal direction.
tstrans – Torsional rigidity in transverse direction.
econc – modulus of elasticity of concrete.
gconc – shear modulus for concrete.
N (ndiv) – Number of divisions in either direction.

Bridge decks are normally comprised of a grillage system of longitudinal and transverse girders. Longitudinal girders are supported at two ends while the extreme edges in transverse direction remain free. Bridge decks need special methods of analysis when subjected to unsymmetrical loadings. Unsymmetrical loading occurs for the following reasons:
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Analysis and Design Of 2-D Tubular Frame Using USFOS Modeling

Analysis and Design Of 2-D Tubular Frame Using USFOS Modeling by
Department of Civil and Environmental Engineering
National University Of Singapore

USFOS is the analytical tool for predicting both the resistance of structures subject to accidental loads and the residual strength of damaged structures after such loads. It is based on finite element modeling. USFOS covers static collapse analysis, non-linear time series dynamic analysis as well as eigenvalue analysis of typically jackets, jack-ups, topsides and floaters. Primarily the purpose of this paper is to analyze two types of 2-D offshore frame and study the progressive collapse mechanism in these two frames due to different load combinations along X-axis and Y-axis. First the boundary conditions were fixed for the vertical members using USFOS modeling and they were tested for collapse under four different load combinations. Differences in behavior of two frames have been studied and different brace-chord sizes have been fixed. This type of analysis is useful to test if an offshore jacket with some specified size can stand the load coming on it from waves, wind or impact of ships. By utilizing the inherent redundancy found in most offshore structures the progressive collapse limit state can be used to design for accidental damage or extreme loads. Whereas in traditional elastic design redistribution of load is not normally considered. Collapse or plastic limit state design allows for local failure in yield or buckling and even partial collapse, provided the overall integrity of the structure is maintained. In short, plastic limit state design allows the designers to take advantage of any reserve capacity in the structure.
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