Interlocking block

Because of the precise reproduction of mould shapes, sulphur concretes are ideal for use in interlocking blocks. Housing has been constructed in the United Arab Emirates (25) and Mexico (26) with such blocks. Also an interesting compression mould, postheat process for simple mass-production of interlocking blocks has been developed at the University of Washington (27) and a number of buildings have been constructed from the product. 

Ashes from incinerated paper industries sludges were studied for their potential use in cement concrete interlocking block. Addition of ashes induced an increase of the water/cement ratios and moisture absorption and a decrease of the flexural strength of cement mortar or concrete. However, such disadvantages could be overcome by adding polymer latex and the interlocking blocks containing ashes met the Korean Standard. 

Keywords Paper sludge ash, interlocking block, polymer latex, W/C ratio, moisture absorption, flexural strength. 

Ash is a chemically stable inorganic material. Thus, there is a potential for their application as a construction material. Possible applications of ashes reported in the literature include asphalt, cement concrete block, road construction, and melt slag (1-3). Recently, we carried out studies on the possible application of ashes from incinerated paper sludges for interlocking blocks. Acrylic latex was employed to improve the properties of cement mortar or concrete modified with ashes. Our results are partly reported in this paper. 

Table 7. Mix formulation of the cement concrete for interlocking block...

In Fig. 4, water/cement ratios of the cement concrete for interlocking block into which ashes were incorporated with and without polymer latex are shown. It is observed that water/cement ratios of the cement concrete increased as the ash contents were increased. It is worthwhile to note that the increase of water/cement ratios for cement concrete with polymer latex was less than that for cement mortar without polymer latex and almost constant. 

In Fig. 5, moisture absorptions (%) of the cement concrete for interlocking block into which ashes were incorporated with and without polymer latex are shown. In case of cement concrete without polymer latex, moisture absorption increased as the ash content is increased. The cement concrete with polymer latex showed less moisture absorption compared with the cement mortar without polymer latex. Furthermore, moisture absorption decreased as the ash content was increased in the cement concrete with polymer latex. It is believed that the decreased moisture absorption of the cement concrete with polymer latex are due to film formation of the latex polymer in the capillary and voids of the cured cement concrete. According to KS F 4419, moisture absorption of the interlocking block should be less than 7%. It seems that addition of polymer latex at least 5% of cement to the cement concrete with ashes is necessary to meet the KS F 4419. 

All the disadvantages mentioned above could be overcome by adding 5% of acrylic polymer latex of cement into cement concrete to make acceptable interlocking block. Interlocking block made from cement concrete into which ash was added up to 10% without polymer latex could meet only the required flexural strength. 

The Mega Bloks company used a process called reverse engineering to design its interlocking blocks so they would be compatible with Lego bricks. is the process of measuring and analyzing... 

OLe Kirk Christiansen, a carpenter from Denmark, designed the first interlocking blocks in 1947. He called his first blocks Automatic Binding Bricks. Mr. Christiansen s workshop was the humble beginning of the now world-... 

Growing software/hardware complexity. A railway system, for example, consists of inlrastructure, logistics and interlocking blocks these require a diverse range of different hardware and software components to interact. 

In the case of loose blocks, an individual block can be lifted out of the revetment with a force exceeding its own weight and friction. It is not possible with the cover layers with linked or interlocking blocks. Examples of the second type are block mattresses, ship-lap blocks, and cable mats. However, in this case, high forces will be exerted on the connections between the blocks and/or geotextile. In the case of blocks connected to geotextUes (i.e., by pins), the stability should be treated as... 

Figure 5.4 represents the relationship between NO supply concentration and NO removal rate of a photocatalytic interlocking block, measured by the flow-through... 

Fig. 5.3 Relationship between UV irradiance and NO removal of photocatalytic interlocking block at NO supply concentration of 1 ppm...

Figures 5.6 and 5.7 show NO concentration at Points A and B and the accumulated NO removal of photocatalytic interlocking blocks for 1 month, respectively [34], Point B is located near to the roadway compared to Point A. As a matter of course, the NO concentration at Point B is much higher than that at Point A. The accumulated NO removal at Point A is 5.7 mmol/m. At Point B near the roadway, the NO removal is 12.3 mmol/m. The accumulated NO removal is increasing after 3 weeks, and the NO removal performance is hold.

Murata Y, Tobinai K (2002) Influence of various factors on removal performance of permeable interlocking block based on photocatalysis. J Struct Construct Eng 555 9-15, Transaction of Architectural Institute of Japan (in Japanese)... 

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