Use Of Concrete Blocks Research Articles

Evaluating the performance and durability of concrete paving blocks enhanced by bio-cement posttreatment

Concrete pavement often experiences accelerated deterioration due to water and chemical ingress through micro-cracks and surface voids. Particularly, the ingress of aggressive agents into the concrete matrix results in irreversible changes and deterioration on its endurance. Numerous studies unveiled that hydrophobic surface protection could be an inexpensive and effective way of enhancing the durability of concrete. This research work aims to assess the feasibility of bio-cement posttreatment for facilitating hydrophobic surface protection, thus enhancing the performance and durability of concrete blocks. Enzyme induced carbonate precipitation (EICP) is one of the promising bio-cement methods. Concrete blocks casted in four different grades were subjected to EICP treatment with different treatment schemes and recipes of cementation media. The treated blocks were tested for water absorption, ultrasonic pulse velocity (UPV) measurements, unconfined compressive strength (UCS), thermal performance, and scanning electron microscopy (SEM). The results indicated that the concrete blocks subjected to EICP posttreatment showed over a 55% reduction in water absorption, a 15% higher UCS and a 6.7% higher UPV when compared with control blocks. The SEM analysis suggested that the EICP posttreatment could enhance the durability of concrete paving blocks by enabling a layer of calcite on the surface and by plugging the transport pore channels of the concrete. Although most of the posttreatment strategies investigated herein were found to be operative, a better response was seen in the posttreatment by spraying scheme with 0.5 mol/L cementation media (CM). With the successful demonstration, the EICP treatment prior to the use of concrete blocks can be recommended to the pavement construction industry.

Feasibility study of the use of concrete blocks produced from plastic marine garbage for use in civil construction.

The pursuit of development in an economically sustainable and ecologically sound manner is a goal of modern society. It has been investing in products that minimize their environmental impact, particularly concerning the use of plastic. This material is highly detrimental to nature due to its toxicity and long decomposition period. The present study aims to analyze the feasibility of producing blocks made of concrete with different amounts of waste plastic taken from coastal and estuarine areas. After laboratory analysis, it was found that blocks containing 5% plastic exhibit good compressive strength and are lighter. Additionally, there was an increase in the acidity of the sample, a decrease in the density of the block, and reductions in both flexural and compressive strength. The prototype, composed of 5% plastic by mass, proves to be efficient for constructing single-story houses. It meets the minimum requirements for normative resistance, effectively encapsulating the plastic within the block and thereby reducing its environmental impact.

Efisiensi Penggunaan Material Blok Beton terhadap Batu Belah pada Pekerjaan Fondasi Dangkal

Shallow foundation work with rubble stone material has several weaknesses, such as surface and shape irregularity and scarcity in a certain location. These weaknesses can be avoided through the use of concrete block material as a positive contribution for this research. This article provides the efficiency in the use of concrete blocks instead of rubble stones in shallow foundation work, by highlighting work productivity and total cost of work for both materials. Data is collected on a wall fence foundation work which implemented both materials successfully in Grogolan, Umbulmartani, Ngemplak, Sleman Yogyakarta Province. This research has revealed that the average productivity on concrete blocks and rubble stones is 0.799 m3/h and 0.590 m3/h respectively, in which there is a time efficiency that concrete block construction is 35,44% faster than that of rubble stone. Total cost of concrete block will be more expensive than rubble stone if the work volume is small, nevertheless it reaches a break-even-point at work volume of 11 m3, meaning that a cost efficiency of concrete block construction occurs if the work volume is more than 11 m3. Moreover, the implementation of concrete block has 4 intangible benefits i.e. saving space usage, minimum waste, ease of work, and more precise product.

Incipient motion of Armorflex articulating concrete blocks on steep slopes

Armorflex is an articulating concrete block erosion protection measure that has been used as an alternative to riprap for many years. Even though extensive research and hydraulic testing have been conducted on Armorflex, the principal constraint on the use of concrete blocks has been the lack of information on prototype performance. Furthermore, there are no standards for Armorflex or articulating concrete block revetments in the South African National Standards, and design guidelines from Armorflex manufacturers are insufficient. The aim of this study was to improve the understanding of the critical flow conditions under which Armorflex blocks are lifted and removed by flowing water in open channel flow applications. Scaled laboratory tests were conducted on Armorflex 140 and Armorflex 180 blocks. Liu's theory of 1957 is applied in an attempt to define the point where block movement is initiated.

Evaluation of the effect of the mechanical properties on the performance of interlocking concrete block pavement under the influence of petroleum products

Recently, there has been an upsurge in the use of interlocking concrete block pavement (ICBP), though large scale and extensive use of the blocks is not commonplace. In some residential districts, the current trend which is seen as a new fad is concrete-block paving of driveways and courtyards of private homes. There is also a gradual increase in the use of concrete blocks for paving pedestrian walkways in recent constructions in the cities, and in rehabilitating old walkways in urban activity centers. The aim of this study is to investigate the effect of three types of petroleum products: Fuel oil (FO), Kerosene (K) and Engine oil waste (EO), on the mechanical and physical properties of interlocking concrete block pavement (ICBP) manufactured from two Iraqi factories, where two types of (ICBP) were chosen one from each factory. 66 specimens were submerged in the petroleum products for 30, 60, and 90 days, then the compressive strength, ultrasonic pulse velocity, density and absorption values were determined and compared with non-submerged specimens. In general, the results showed that ICBP-2 has good resistance to the effect of kerosene and fuel oil.

Projeto residencial moderno: pré-fabricado e modulado na obra de Wright

This paper investigates the residential architecture of Frank Lloyd Wright, especially the designs which were conceived from an idea of prefabricated, modular, low-cost, and high-scale construction. Wright's organic designs originated from a material-based grid, which at the same time organized and provided freedom to create spaces and forms. This study reviews Wright's work, from his first Midwest designs that relied on brick, through an intermediary phase in California when he made intense use of concrete blocks, until his last phase, the usonian houses, which featured wood paneling. During his early career, the concept and the methodology of Wright's ideas greatly contributed to a better understanding of his architecture, his apprentices and his followers. The economy and rationalization found in the projects reviewed are of great importance as the analysis of historical proposals helps us understand the topic in question.

The Environmental Impact of Coral Mining on Coral Reefs in the Maldives

Demand of the construction industry for coral rock in the Maldives will soon reach the limit of supply capacity using existing collection techniques. It is estimated that, at the current rate of consumption, the supply of living coral rock from inner atoll ‘faros’ in North Malé will be exhausted within 30 years. Current mining practice has already necessitated the collection of living coral rock from outer atoll ‘faros’ which actually protect the integrity of the islands against the erosive influences of monsoon storms.Biological surveys of mined sites (compared with controls where no mining activity has taken place) indicate a dramatic reduction in coral variety and abundance and in some cases an almost total depletion of living coral after mining. At intensively-mined sites, diversity and abundance of coral-reef fishes is also markedly reduced, with some reef species commonly used as baitfish entirely absent. The time taken for reefs to recover from mechanical damage has been shown by other research work to be extremely variable, with some cases showing no recovery in some circumstances. Shallow-water reefs that have been colonized by slow-growing ‘massive’ corals, such as those which have been mined in the Maldives, may take a minimum of 50 years to recover to their former state—under optimum conditions.Observations on mined reefs in the Maldives show that recovery over the last 10 years has been minimal, and therefore suggest that recovery times may be much in excess of 50 years. Indeed many of these reefs may not recover at all unless some attempts are made to re-establish corals at these sites. It is also clear from the study of reclaimed and dredged sites and those where less-intensive mining has taken place, that regeneration of corals is occurring. It is quite probable that the rate of recovery is dependent on the intensity of the disturbance which initially took place.Alternative building materials are available in the form of concrete blocks. Use of these blocks is more cost-effective than use of coral rock; however, there is a lack of any quality control, which would be needed to promote the widespread use of concrete blocks as a substitute for coral. Recently, recommendations have been approved by the Government of Maldives for the execution of a feasibility study on mining an inner atoll faro which could potentially provide building material for as long as the next 500 years.

THE BEHAVIOUR OF A CONCRETE BLOCK PAVEMENT.

This paper describes the construction and testing of a concrete block pavement. The test pavement, 6 M x 3 M, was constructed on a heavy clay subgrade; it had a tapered sub-base varying from grossly inadequate to reasonably strong. The effect of sub-base thickness on surface deformation and the development of interlock between the individual blocks are examined and various types of failure described. The overall behaviour of a block pavement is compared to that of traditional asphaltic materials and conclusions are drawn regarding the depth of sub-base required for UK roads. Before describing the experiment the paper gives a brief history of the use of concrete blocks both in the UK and abroad. /Author/TRRL/

Making and using concrete blocks

The concrete block should be recognised in its own right, not as an alternative to other materials, the author suggests. Mr. McIntosh, who is based at the Wexham Springs Laboratories of the Cement and Concrete Association in the UK, is the author of ‘The Manufacture and Use of Concrete Blocks for Walls’, Overseas Building Note No. 150 published by BRE, from which this article has been extracted.

Harbors: The Preparation and Use of Concrete Blocks for Harbour Works

Harbors: The Preparation and Use of Concrete Blocks for Harbour Works