density 1800 kg/m3 with cylindrical compressive strength of 40 Mpa by the use of silica fume , The naturally occurring tuff aggregates which are available in north- eastern Jordan produces high strength lightweight concrete. The results shown that for various concrete mixes, and using normal techniques it is able to achieve a high-quality lightweight concrete which is appropriate for the use in reinforced and prestressed concrete structures, with maximum compressive strength of 60 Mpa at 90 days, poison ratio for this type of concrete which was moist cured is found to be 0.21 which is nearly equal to poison ratio of normalweightconcrete .
The compressive strength of high and normalweightconcrete is considerably affected by the quality of coarse aggregate. The Margala Hill limestone aggregate (19-4.75 mm), together with the ground granulated blast furnace slag and the Qiblabandi sand (Fineness Modulus=2.7) appeared very promising for application in the concrete classes A1, A and B, which belong to the normal and high weightconcrete classes. Moreover, Margala Hill limestone used as coarse aggregate in different concrete types on various structural components of the barrage has displayed the highest compressive strength value in A1-type concrete, even at the age of 7 days. All of the trail mixes exhibited a workable slump, which indicates their suitability for girders, the main weir and for block aprons of the barrage. Based on these compressive strength values, it is concluded that the amount of cement and slag can be reduced to design an economical concrete mix.
The study investigates a macro scale fracture process of concrete cylinders under axial compression. It takes into account the mixed mode fracture phenomena (the implication of the opening mode besides the sliding mode which was employed and studied before (Sih 1984, Comninou 1990, Yuuki et al 1994, Ohtsu et al 2011)).The main objective is the development of model equations to predict both the tensile and shear strength of normalweightconcrete from the direct compression test of two cylinders separately in the existence of friction between the loading platens and concrete cylinders. The two cylinders should have a same cross- sectional area, but are of different heights. The aim of employing two cylinders is to introduce a new concept of characteristic fracture angle or the direction angle of the failure plane as a function of concrete strength.
A concise conversation on the difference involving lightweight and normalweightconcrete is desirable due to the design differences in the quality and density of aggregate. Numerous tests have been conducted on normalweightconcrete but very few tests have been performed on lightweight structures. The term lightweight concrete itself describes a wide range of special aggregate bases. The specific gravities and in terms of density of compactness of these aggregates are significantly lower than that of normalweightconcrete aggregates. Air is naturally trapped in the aggregate from its origin which causes the reduced weight of the concrete mixture. The properties of lightweight concrete vary with the type of aggregate and the source and size of the aggregate.
results are listed in Tables 8 and 9, including results of normalweightconcrete composite beam test (NWB), lightweight concrete push-off test (LCP), normalweightconcrete push-off test (NWP), and high-strength con- crete push-off test (HSP). Additionally, all of these speci- mens were failed in interface shear. Table 10 shows the comparison of proposed equation with the experimental results of other researchers listed above. To be clear, the evaluation of proposed interface shear resistance equa- tion is also plotted in Fig. 12. It can be seen that Eq. (10) gave a conservative predicted for HSP with value of 0.79 for the mean of predicted/experimental results. On the contrary, Eq. (10) represented an accurate prediction for NWB, LCP and NWP with rough shear plane. For smooth interface condition, the average mean values of predicted to experimental results is 1.11, which demon- strates that the Eq. (11) can be potentially used to predict the smooth interface shear capacity of composite beam test, or the push-off test made of normalweight, light- weight or high-strength concrete. However, the authors suggest that more experimental data of interface shear resistance between normalweight and lightweight con- crete are needed to verify the applicability of the pro- posed empirical equations.and interlock action.
Two concrete mixes, one is normalweightconcrete (NWC) and the other is lightweight concrete (LWC) were prepared. The normalweightconcrete used sand and gravel as fine and coarse aggregate while the lightweight concrete used crushed clinker as fine and coarse aggregate. Both concrete mixes were proportioned according to Building Research Establishment . Since clinker is an industrial waste, several tests have been carried out in order to obtain some basic properties of these lightweight aggregates. The test results were then checked with appropriate standards to ensure the suitability of clinker aggregate to be used in lightweight concrete mixture. Table 2 shows the basic properties of clinker aggregate in the form of fine and coarse aggregate. The coarse clinker aggregates had a maximum size of 10 mm and satisfied the BS 3797 grading limit.
In this paper beam column joint connection were studied under static loading. Two circular CFST column steel beam connection and two rectangular CFST column steel beam connection designed according to AIJ code. Total four specimens were designed with circular and rectangular diaphragm connection. These specimens were compared for material and shape of connection. Specimens were analyzed by using ANSYS software. From these results concluding remark were discussed. The details of specimen were listed in table no. 1 and material properties are listed in table no.2. The size of circular column joint is of 40x9.6mm and for rectangular column it is of 40x40x9.6mm. Normalweightconcrete and light weightconcrete of grade M40 is used to fill column. for steel young’s modules is 201 GPa and poisons ratio for steel and concrete is 0.3 and 0.2 respectively.
in workability of concretes incorporating coarse RCA, due to the increased angularity and surface roughness of RCA when compared to natural coarse aggregates. This is of particular importance for the increasingly popular form of concrete known as Self-Compacting Concrete (SCC). The Eurocode defines SCC as concrete that is able to flow and compact under its own weight, fill formwork with its reinforcement, duct box houses, and so forth, whilst maintaining homogeneity. It is a relatively recent form of concrete construction having been developed in Japan in the mid-1980s and introduced in Europe in the mid-1990s. Despite its recent development, SCC is now widely used in industry due to the advantages of SCC which include increased on-site productivity, enhanced construction quality, and improved working conditions on-site. However, as pointed out by Tuyan et al., the cost of SCC is higher than traditional vibrated concretes due to the need for higher powder contents and chemical admixtures in SCC. Thus in order to allow SCC to reach its full potential in terms of industry uptake it is necessary to develop ways of making SCC more cost-effective. The use of coarse RCA as substitutes for coarse natural aggregates in SCC offers a means of reducing the cost of SCC, while reducing the carbon footprint of concrete production. Consequently, there are both business case and an environmental obligation to explore the use of RCA in SCCs.
1.3 SEISMIS ANALYSIS OF RC FRAMES WITH INFILL WALL While analyzing multi storey buildings, designers usually neglect the contribution of masonry infill in resisting loads. They consider only dead weight of masonry and analysis is done by bare frame method. It is very common now days to construct multistoried buildings with open ground storey. Since there is a sudden change in stiffness at first floor level, ground floor columns will attract greater horizontal force and hence they should be designed for a larger force than that obtained using bare frame analysis. As per IS 1893:2002, the columns and beams of the soft storey are to be designed 2.5 times the storey shears and moments calculated under seismic loads.
Abstract: As we grasp that Concrete is forceful in pressure however weak in strain and firm too. Splits start establishing from the period concrete is expressed sited. A few drawbacks in concrete don't permit the utilization of normalconcrete in various constructional functions as they lead to nonexistence of flexibility alongside break and disappointment. These obscurity in cement can be uninvolved by expending fibers as support in the solid combination. Non-biodegradable squanders like polyethylene and tires cause biological contamination which lead to different wellbeing hitches. Polyethylene and overabundance tires can be reused and utilized solidly in the solid as fortification as fiber. Polyethylene is a fake hydrocarbon polymer which can upsurge the flexibility, quality, shrinkage physiognomies and so forth. This paper the home-work is done about the outcome of expansion of Polyethylene fiber on the benefits of cement. Polyethylene and tire strands where cut into the different and disconnected sizes and they were utilized in concrete. Assessment of cement utilized were M.30, M.35. IRC 44: 2008 was shadowed for the technique of solid blend. In this preparation, the aftereffects of the quality assets of Polyethylene fiber strengthened cement have been advertised. Four bowing test and offer test were done in lab for flexure and shear quality reason.
an exact cause. In most situations the realization of such upgrading can only be achieved cost-effectively and more rapidly when suitable admixtures are used. The choice to investigate into the use of sawdust ash as admixture in concrete may enhance the economic standard of wood workers by utilizing the waste material to generate assets and will also serve as a cheaper alternative to that of conventional admixtures, with a consequent reduction in the cost of construction and also as a means of addressing the environmental pollution caused by the accumulation of unmanageable waste.
The connection push-out test setup which was performed in the Structures Laboratory of the Department of Civil and Natural Resources Engineering, University of Canterbury is illustrated in Fig. 3-6 (in main text) and described in Section 4.4 (in main text). 50 mm potentiometers with ±0.4% accuracy: P1, P2, P5 and P6 (Fig. A5-1(a and b)) were used to measure relative slips in connection potentiometer P3 for horizontal slip (Fig. 3-6 in main text). Horizontal slip was measured to observe possible separation between LVL and concrete and to aid in determining whether there would be a problem with the flanges of the specimens separating from the LVL web and falling out, possibly damaging equipment or injuring someone. One specimen was tested without any form of restraint, and it was found that significant separation occurred due to the bending moment induced in the specimen by the load. Since in the actual timber-concrete composite beam the connections are loaded in pure shear and separation between the concrete and timber is not likely to occur, it was decided to prevent the separation in the specimens using steel straps. These were placed at the top and bottom of the specimens for two tests and then the bottom strap only was used for another two tests. It was found that the strength values were almost identical for having two restraints or only one restraint at the bottom; therefore it was decided to just use the single strap at the bottom of the specimens for the rest of the testing.
The prevalence of normalweight central obesity in this study of 34.4% - 39.2% depending on the criteria used, is higher than 15.4% reported among Thai health workers  and 26.9% - 36.9% among South African adults . Persons with normalweight and central obesity have been found with higher mortality risk than with similar BMI but no central obesity . The high prevalence of nor- mal weight central obesity observed in this study is suggestive of the need to in- clude central obesity measures alongside BMI in both preventive and manage- ment clinical care practice for NCDs. Use of BMI alone may not capture all at risk individuals  . Besides physical activity level and dietary habits, gesta- tional weight retention has been associated with obesity among postpartum women . More than a third of the participants had either high or very high health risk based on NICE BMI-WC composite index. This calls for follow-up programs for mothers after delivery by the Kenyan health ministry as part of strategy to curb rising obesity and the associated health risks.
FC-Lite frothing specialist is a natural material and in that capacity bio-degradable. It is delivered of creatures hooves/paws and horn, which are totally clearned of pollutions, precisely diminished in size before being proceed in as autoclave (weight vessel). Different segments are been included amid or impact the frothing operator generally. The hydrolyzed fluid is the been sifted. FC-light frothing operator ought not be put away under temperature above 30o Celsius, nor presented to coordinate sun. The drums must be kept water/air proof. Whenever followed these proposal, FC-light frothing specialist must not be carried into substance with some other item and surely not with oil, which is know to impact the surface strain of the water and consequently to the froth to be created. Any control/siphons/channels utilized , should in this way be total artificially clean. There are an extraordinary no of engineered frothing operator been offered to likewise tp produce cell concrete. None of these anyway can coordinate protein based frothing specialist in soundness. The precisely and physical properties of such cell concrete are not adequate to permit most extreme proportions of thickness over quality.
Lightweight concrete can be produced in a practical range of densities between about 300 and 2000 kg/m3, using three methods. The first is so-called no fines, where the fine portion (sand particles) of the total concrete aggregate is omitted. The second method is by introducing stable air bubbles inside the concrete body through mechanical foaming and chemical admixture. This type of concrete is known as aerated, cellular or gas concrete. The third and most popular method is by using lightweight aggregate. This may come from either a natural or an artificial source.
Fiber reinforced concrete (FRC) may be defined as a composite materials made with portland cement, aggregate, and incorporating discrete discontinuous fibers. Now, we wish to add such fibers to concrete because plain, unreinforced concrete is a brittle material, with a low tensile strength and a low strain capacity. The role of randomly distributes discontinuous fibers is to bridge across the cracks that provides some post-cracking (ductility). If the fibers are sufficiently ductile, the Fibers could be capable of carrying significant stresses over a relatively large strain capacity in the post-cracking stage which characteristic is the case of corrugated steel fiber. The real contribution of the fibers is to increase the toughness of the concrete. Also, fibers tend to increase the strain at peak load and provide a great deal of energy
The objective of this test is to achieve in decrease in room temperature when compared to the atmospheric temperature. A prototype of a building was made to act as a specimen. The above models were made with dimensions 50 x 70 x 25 cm with the use of available concrete blocks in the site. The outer surfaces of the models were plastered with OPC blended with different proportions of vermiculite ranging from 0% to 15%. the models were cured as same as the curing done to normal buildings. Holes were dug in the bonding area between two respective blocks to insert the thermo couple. A thermo couple is an instrument that is used to measure the internal temperature. After curing period the models were left to normal atmospheric conditions. The internal temperature and the atmospheric temperature were noted at every 1 hour interval for the various models plastered with various proportions.
Abstract—This paper explores the cyclic behaviour of the high performance concrete and also describes influence of steel fibres in the HPC beams. The high performance concrete mix with M60 grade was designed using ACI 2411.4R. An experimental investigation of the behaviour of HPC beams reinforced with normal steel bars and steel fibres under cyclic loading is tested and the results are presented in this paper. In this study 9 R.C.C beams were casted using high performance concrete, which includes control beam that consists of normal mix without steel fibres. And remains R.C.C beams consists of two different volume fractions (0.75% and 1%) of steel fibres with two different aspect ratio ( 60 and 50). All beams were tested under full cyclic load to establish load-deflection curve and the results were evaluated. The results also show that inclusion of steel fibres intensify the ductility, Stiffness and residual strength. Inclusion of steel fibres has proven to resist the stiffness degradation after applying four number of cyclic loading on the HPC beam.Studies revealed that, the use of fibres in concrete for the construction purpose to decrease the cracks as well as strength.
Construction officials in coastal areas have long been facing the challenge of building and maintaining durable concrete structures in a saltwater environment. Gradual penetration of sea salts and the subsequent formation of expansive and leachable compounds lead to disintegration of structural concrete. The average NaCl concentration of sea water is about 3.5% although it varies from sea to sea depending upon geological location. In this study bagasse ash is used because it is one of the main by product can be used as mineral admixture due to its high content in silica (SiO2).In this study, Bagasse ash has been chemically and physically characterized, and partially replaced in the ratio of 0%, 5%,10%,15% and 20% by weight of cement in concrete. Fresh concrete tests like compaction factor test and slump cone test were undertaken was well as hardened concrete test compressive strength at the age of 7,28 and 60 days was obtained. The result shows that the strength of concrete .Concrete specimens were cured in normal water and NaCl solution and comparison is made between them.