This experimental work is about the study of drying shrinkage followed by strength testing of lightweight foamed concrete (LFC) specimens with the confinement of woven fiberglass mesh (FGM) at three different densities. The LFC specimens were wrapped with 1-layer to 3-layer(s) of FGM for cube and cylinder specimens and in beam specimens, it was centrally spread along the longitudinal axis. The specimens were cured under air storage conditions and the drying shrinkage test was carried following ASTM C157/C 157M specification on three prism-shaped '75mmx75mmx285mm' specimens. NORAITE PA-1 foaming agent was used to produce the desired density of LFC. All of 324 specimens were cast and tested for mechanical properties at 7days, 28days and 56days respectively. In compression strength test, cube dimensions of 100mm side following BS EN 12390-3:2009 was adopted. The flexural strength was conducted on '100mmx100mmx500mm' beam specimens following BS ISO 1920-8:2009. The specimens '100mm in diameter and 200mm in height' were tested for split tensile strength considering ASTM C496/ C496M-04e1 specifications. The results showed that confinement with 160g/m 2 (GSM) of FGM significantly restricts the drying shrinkage of LFC specimens compared to control specimens and it decreased with the increases in layer(s) from l-layer to 3-layer(s) and density of LFC. The testing of the mechanical properties of LFC showed a direct proportionality between strength and LFC density and confinement layer(s). The failure pattern observed in all specimens was either by debonding or splitting of fibers of FGM. Thus, LFC at 1600kg/m 3 density confined/reinforced with 3layers of FGM conquers the good performance in drying shrinkage and strength properties while the poor performance was shown by the unconfined LFC at 600kg/m 3 density.

Researchers and decision makers are continuously looking out to determine the potential and effectiveness of fly-ash as a partial replacement of cement in concrete. The current study is carried out to check the optimum or nearly optimum quantity of fly-ash with which cement should be replaced to get most of the properties of concrete enhanced and to give the idea about the quantities of fly-ash that can be used in a better way and better cause so that a proper management scheme of its usage and disposal can be implied. Further, a comparison is given between normal concrete and fly-ash concrete to show the properties which can be enhanced by proper utilization of fly-ash as a partial replacement of cement. After carrying out the lab experiments, it has been seen that the replacement of fly-ash in concrete has resulted in general increase in compressive strength, flexural strength and splitting tensile strength up to 15% replacement and after then the strength is decreased considerably than that of normal concrete. Addition of fly-ash in concrete has resulted in decrease in the water absorption of concrete and hence decreases in permeability of concrete. There is a progressive increase in workability with increase in percentage of fly-ash in concrete. The current study has led to a conclusion that in order to achieve best results in use of fly-ash concrete, the fly-ash used for replacing cement in concrete should have the required properties as specified by the standards and proper techniques of processing fly-ash as well as mixing of fly-ash with cement must be employed.

In the present study performance evaluation of nano-modified cement polymer anticorrosive coating (CPAC) was undertaken by conducting the Chemical Resistance Test (CRT), Applied Voltage Test (AVT), Bond Strength Test (BST), Accelerated Corrosion Test (ACT) and Coating Flexibility Test (CFT). The site oriented coating comprises of nitrite, styrene-butadiene polymer and other additives. The anticorrosive polymer solution is compatible with concrete or cement when uniformly mixed with fresh ordinary portland cement (OPC). Totally forty-five specimens were subjected to various performance evaluation tests. In CRT observations were made on drilled and undrilled specimens after 45 days test period in liquid and vapour phase. The coating did not blister, soften and lose bond in all the tested medium during CRT and meet the requirement of BIS 13620-1993 and ASTM A775/A775M.The coating has the ability to withstand the electrochemical stresses during one-hour AVT. In the BST, single and double coated rebars showed +126.96% and +46.08% greater usable bond strength respectively than uncoated rebar. In the ACT, there is a significant escalation in time of cracking of specimens of double-coated reinforced rebars by 2 times as compared to uncoated rebars. Cracking time for single coated reinforced rebars was found 1.6 times more than uncoated rebars. In the CFT, coating completely in the inner and the outer radius of the 180° bend rebar fails to meet the requirements of BIS and ASTM standards. Thus the coating has to be applied subsequent to cutting and rebar twisting is finished.

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