Volume:4 Issue:5 May ' 2018
||Durability of Nano-Modified Concrete Cured Under Different Regimes
Durability of Nano-Modified Concrete Cured Under Different Regimes
This study presents the effect of using different curing regimes water (W) and lime water (L) and different dosages of nano silica (NS) (0, 1.5, 3 and 4.5%) replacement by wt. of cement on both mechanical and physical properties of concrete. The mechanical properties were investigated through compressive and tensile strengths while the physical properties were evaluated through permeability and abrasion resistance of concrete. It was found that; for both curing regimes, using 3 and 4.5% of NS gives the best performance of concrete in both mechanical and physical properties, respectively. It was observed that the NS; especially when cured in lime water, can enhance the filling effect of concrete in addition to the formation of high stiff C–S–H gel due to its ultra-high pozzolanic activity. The gain in compressive and tensile strength reached 120% and 87% by using 3% NS after 28 days of curing in Lime water, respectively. However, the gain in the abrasion resistance of concrete reached 25% using 4.5% NS and lime water curing regime. The NS concrete permeability reduced to be only 41.5% of normal concrete using 4.5% NS and lime water curing regime.
||Design and Development of Box Transport Mechanism
Design and Development of Box Transport Mechanism
There has been a serious demand for intermittent movement of packages in the industries right from the start. Though the continuous movement is more or less important in the same field of the sporadic motion has become essential. The objective of this study is to design a mechanism that delivers this stop and move motion using the mechanical linkages. The advantage of this system over the conveyor system is that the system has a time delay between moving packages and this delay can be used to introduce any alterations in the package or move the package for any other purpose and likewise. While in the normal conveyor mechanism such actions cannot be performed unless programmed module is used to produce intermittent stopping of the belt which is basically costly. The prototype design requires an electric motor, shafts and the frame of which, the frame and platform on which the packages are moved is fabricated. All the links are made up of normal MS (mild steel) and wood including the head which has a direct contact with the boxes that are to be moved. The system is expected to move as heavy packages as 2 KGs approximately. The aim of the project work is to design and fabricate a box moving mechanism that makes much easier to move with the so called quad staying machines by means of which a box blank is folded or set-up into box like form. These set-up boxes are transferred by means of a conveyor to an operator, who picks up the boxes and places and centers’ them on wrappers with which the boxes are to be covered. The boxes and wrappers are then conveyed to a box wrapping machine where the wrapper is folded around and glued to the box. Usually, the operation of the wrapping machine is controlled by means of a switch actuated by the box forming machine so that their operating speeds are related to each other.