Low Cost Building Materials

Crisis: Turning point in a disease (for better or worse) - Hippocrates

Previous economic growth and the relatively low number of practicing professionals in Portugal allowed architects such as Álvaro Siza (2012) to work mainly through commissions made by government entities. According to Costa (2013), the international recognition of these architects led to an influx of students into architecture schools. Recent research (Caldeira,
Santos and Ravara, 2013) shows that an excessive number of recently graduated architects together with the decline in the construction industry gave rise to high unemployment rates among Portuguese architects. Some of them, consciously or not, went looking for work in the fringes of the discipline. They are characterised by a multitude of attitudes working on transdisciplinary projects. They do not have any commissions, they reinvent sustainable models leading to self-built, ephemeral constructions, minimal interventions without design, self project financing or fund raising. They are networked, grouping and ungrouping quickly not only locally but worldwide. Architect designed political interventions appear on the streets. Some embrace social causes and others design only digital projects.
If the architecture of the preceding generation was intended to last one hundred years or forever, now it is designed to last one week or never to be built allowing an increased design freedom. The building materials of the preceding generation were limited to stone, concrete, glass and wood. Now the range has been extended to plastic, earth, wax, mirrors, paper, live animals, ready-made and pixels. They ask themselves frequently what
can we do with €500? Or what can we build in one week? They re-invent the meaning of the word architecture. Baptista (2010) suggests that this happens not because they don’t want to do the previous architecture, but because this is the only architecture they can do.
The architect’s practice and education needs to change not only to suit challenging economic times but due to restrictions of our finite world: super populated, connected, fully explored and with increasing levels of consumption. Students sometimes have expectations to design through massive amounts of material and human labour. This is an issue which will become increasingly difficult to do.
Learning with the Portuguese example we are applying their tactics in Design Studios in Austria and Australia, countries not hit by monetary constraints. Instead of asking students to draw proposals on paper or models, we ask them to actually build something with a low budget in a short time. Not models but 1/1 finished products that, due to their resource scarcity, will achieve maximum impact on their audience. The evanescent character of these proposals allows great freedom in students’ designs.

Cost escalation refers to the changes occurring in cost of specific materials services in a given economy over a period of time. Construction industry is a most complicated and dynamic industry which is constantly facing uncertainties. The various factors that cause escalation in construction industry are studied and discussed in the article. The ideas suggested by researches were also analyzed and reported cost escalation can be minimized to a greater extent by carefully adopting the remedial measure.

Natural coral stone is used as a building material for coastal settlements throughout the Indian Ocean, Arabian/ Persian Gulf and the Red Sea. It remains a favored building material along the coastal region because of its functional and decorative characteristics despite the lack of standards and specifications for the building stones. In Kenya, coral deposits are found along the coastal region in places like Lamu, Kilifi, Vipingo and Mombasa among others. When used as a building material within the coastal region, it may provide a boost to low cost housing project in the region.
Two different samples of coral stones have been obtained from the South Coast (SC) and the North Coast quarries (NC) of the Kenya’s coastal region. An investigation into their durability, weathering and strength (compressive and tensile) properties have been done through laboratory tests that have been carried out in accordance with the Kenya standard for tests on natural building stones obtained from the Kenya Bureau of Standards (KEBS) headquarters, Nairobi-Kenya.
The weathering test results have been reported in terms of the percentage increase in absorption and percentage increase in volume of the samples and have been found to be X and Y respectively for North coast samples and X and Y respectively for South coast samples. Similarly the durability test result has been reported in a percentage as change in weight and has been found to be X for NC samples and Y for SC samples. From the results, the dry condition compressive, flexural and tensile strengths have been found to be 3.34 N/mm2, 2.68 N/mm2 and 0.48 N/mm2 while the saturated condition compressive, flexural and tensile strengths have been found to be 3.13 N/mm2, 2.20 N/mm2 and 0.44 N/mm2 respectively for NC samples. SC samples gave dry condition compressive, flexural and tensile strengths of 2.67 N/mm2, 2.16 N/mm2 and 0.38 N/mm2 and saturated condition compressive, flexural and tensile strengths of 2.10 N/mm2, 1.68 N/mm2 and 0.35 N/mm2 respectively. These values compared favorably with the specified values of the most commonly used natural building stone in the region-Limestone and tuff.

Observations from past earthquakes have shown that the major loss has been incurred due to the failure of masonry walls. The behaviour of masonry infill wall system is complex due to different face interaction between bricks, mortar and concrete frame. To address this issue, skin reinforcement has been provided on the surface to prevent the falling of the masonry walls. For the study, three different types of meshes, namely, welded mesh, chicken mesh and sieve mesh were taken. The elongation of the Chicken mesh was 65% indicating that it has more ductility, a property appropriate for enhancing the performance of the walls subjected to lateral forces. Cyclic load tests on bare frame, frame without mesh and frame with mesh, demonstrated a comprehensible increase in the stiffness, load carrying capacity and energy dissipation when chicken mesh was incorporated in the wall.

Strengthening of existing reinforced columns in old structures is becoming a major issue
during repair and maintenance. Reinforced columns in a structure get distressed due to various
reasons like aging, deterioration of materials, corrosion of steel and abnormal loading conditions like
earthquake, fire, higher wind loads, shock loads and blasts, etc. Retrofitting of existing buildings to
meet safety requirements in seismic areas where older constructions were not designed for
earthquake actions. Other typical application of strengthening techniques can be found where the
bearing capacity has to be increased because of the change in the use of structure, retrofitting reduces
further destruction of historical structures, industrial structures, urban transport structures, marine
structures and earth retaining structures.
There are different methods for strengthening of existing structures. Jacketing is one of the
most popular method for columns. Steel jacket, reinforced concrete jacket, fiber reinforced polymer
composite jacket, etc are most common examples of jacketing. Strengthening of concrete member
with externally applied steel and Ferro cement is an accepted option for repair and rehabilitation of
structures, which will improve the load carrying capacity together with ductile characteristics,
required in the case of seismic retrofit.
In this study, two methods of retrofitting of short reinforced concrete square columns were
attempted. Wire mesh mortar jacketing (WMM) and Steel Cage Mortar jacketing (SCM) were given
to the reinforced concrete column. For analysis of test results, a plain reinforced column (CS) was
tested. A total of 9 column specimens were tested after 28 days and results were analysed.
The design and the testing was done as per the Indian Standard. Results were analysed for
SCM and WMM. Theoretical capacities of columns were calculated and compared. The stiffness
variation for various columns are presented. The energy absorption was obtained from load versus
axial shortening graphs.From the result analysis, it was observed that when compared to control specimen CS, WMM
was 1.75 times greater, SCM was 2.28 times greater. The stiffness of WMM was the highest value
initially, 1.2 times higher that CS. The energy absorption was 5.01 times higher for WMM than CS.
Finally, from the strength consideration SCM is preferred. From the stiffness and energy
absorption consideration WMM is preferred.
Keywords: Concrete-Restoration-Steel Jacket.

The increasing cost and scarcity of portland cement has impacted negatively on the delivery of affordable housing and infrastructural development in many parts in Sudan, especially in Darfur. This paper focused on the evaluation of the pozzolanic characteristics of the volcanic ash obtained from Jebel Marra (mountains) west of Sudan as potential Supplementary Cementitious Materials for use in blended cement and concrete. The study investigated the chemical, physical, and mineralogical characteristics of the volcanic ash and its reactivity toward lime and cement, in addition , the compressive strengths of blended mortar containing volcanic ash in percentage addition were tested at 7, 28, and 90 days. X-Ray Fluorescence and X-ray diffraction techniques were used for chemical and mineralogical analysis respectively. The results of the chemical analysis showed that the sum oxides of Silica, Alumina and Iron were 83.75%. The strength reactivity with lime was 4.2Mpa, while the 28-days compressive strengths for the replacement level with cement 10%, 20%, 30%, 40%, and 50% were 38.9, 35, 29.33, 28.64, and 25 Mpa respectively, against 41.33Mpa., for the control mix. These results indicated that the Jebel Marra Volcanic Ash possesses pozzolanic characteristics and is thus potential cementitious material for use in blended cement.

An effort for an alternate approach in the manufacturing of brick was accomplished by using industrial byproducts like class F fly ash, granite dust and sludge lime as key ingredients. In India thermal power plants and granite industries are generating fly ash and granite dust in large quantities. Industrial waste are hazardous in nature, their disposal is of major concern. Recycling such wastes by utilizing them into building materials is a moderate solution for the pollution issues. Much of an emphasis is laid on energy saving and economy. In this paper an attempt is made for such an alternate approach.

This study describes adsorption effectiveness of Acacia nilotica pod powder in removing Cu 2+ ions in order to consider its application in wastewater purification. The batch method has been employed, using metal concentrations in solution and the percentage adsorption was determined for the adsorption system as a function of adsorbate concentration. Effects of the temperature of the Cu 2+ ion solution, pH, contact time, metal concentration, and adsorbent loading weight on the removal process were also investigated. Langmuir, Freundlich isotherms were applied to experimental data and the goodness of their fit for adsorption was compared. Thermodynamic parameters, like enthalpy ( ) and the entropy ( ) were also calculated. A. nilotica pod powder proves to be a good adsorbent for Cu 2+ ion removal from wastewater.

Strengthening of existing reinforced columns in old structures is becoming a major issue during repair and maintenance. Reinforced columns in a structure get distressed due to various reasons like aging, deterioration of materials, corrosion of steel and abnormal loading conditions like earthquake, fire, higher wind loads, shock loads and blasts, etc. Retrofitting of existing buildings to meet safety requirements in seismic areas where older constructions were not designed for earthquake actions. Other typical application of strengthening techniques can be found where the bearing capacity has to be increased because of the change in the use of structure, retrofitting reduces further destruction of historical structures, industrial structures, urban transport structures, marine structures and earth retaining structures. There are different methods for strengthening of existing structures. Jacketing is one of the most popular method for columns. Steel jacket, reinforced concrete jacke...

The valorization of gypsum (by-product of phosphoric acid production) into useful product seems to be of important interest. In this study, the adsorption of lead (II) and cadmium (II) in an aqueous solution using both commercial gypsum (CG) and industrial gypsum byproduct (IG) as adsorbents, has been investigated. The use of highly-purity CG allows the understanding of the adsorption phenomenon. The use of an IG as received from an industrial site allows the evaluation of its reactivity compared to pure CG. The adsorption experiments were carried out at ambient conditions for 24 h and the pH was recorded along the reaction. FTIR analyses were performed in order to examine the modification in the sulfate bound arrangement in the case of use of lead and/or cadmium. The obtained results have shown that the retention capacity of lead (II) and cadmium (II) by IG was similar that those obtained in the case of CG. However, gypsum by-product may be used as an alternative material to remove heavy metals in wastewaters.

This paper tries to analyze a procedure for a flexible system construction in order to realize a multi-scale prototype for Primary Health Care (PHC) adaptable in different context.
While Emergency Medical Assistants (EMA) is delivered in disasters or emergency situations, Primary Health Care is based on a support as part of overall development constructing as best multi-purpose facilities that can be adapted as a social structure for different tasks and activities, building new facilities. With this approach, we examine the process of building system structure for different functions by adapting the flexible system to the different settlements.
The aim is to define guidelines for a new constructive system through modular and reproducible elements using local resources. However this paper provides an example of evaluating the strategy, combining few different characteristics that can be generalized to build comfortable and flexible spaces for different activities.
A case study focussing on Mozambique will demonstrate how the “Primary health care” approach needs a flexible and adaptable method able to acquire the principle of self-sufficiency with “open” systems, avoiding fixed solutions. The search result is primarily to define a flexible, expandable and versatile facility through a construction system and a logical settlement that can be expanded according to the requirements of the site. It needs relate to the different application contexts also in finding construction materials, as well as typological and localization models of each local settlement.