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Compressive strength and slump flow of self 
		compacting concrete uses fresh water and sea water

Compressive strength and slump flow of self compacting concrete uses fresh water and sea water

SCC concrete has high fluidity that is able to flow and to pass without segregation of reinforcement material and fill the spaces in the mould with little or no compaction process, resulting in a more impermeable concrete. This paper discusses the effect of sea water as mixing water on workability of the fresh state of the SCC (slump flow test and T50) as well as an increase the compressive strength of the SCC using sea water and fresh water as a comparison. Test of Slump flow and T50 using standard EFNARC. The compressive strength was tested using ASTM standard 39 / C 39M - 99. Tests were conducted at ages 1, 3, 7, 28 and 90 days. The results showed that the slump flow of SCC using sea water is smaller than that using the freshwater SCC. SCC uses sea water has an excellent workability, segregation and aggregate does not seem equitable. The increase in compressive strength in SCC uses sea water has differences with SCC using fresh water at the age of 1, 3, 7, 28 and 90 days by 11%, 9%, 3%, 0% and 0%. The increase in compressive strength of concrete SCC uses sea water very quickly at the early age at the age of 1 and 3 days compared with an increase in the compressive strength of concrete SCC uses fresh water. The increase in compressive strength SCC uses sea water at the age of 1 to 28 days is greater than the SCC that uses fresh water, but otherwise at the age of 90 days.

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How career changes affect technological breakthrough   Reconsidering the prolonged slump of the Japanese economy

How career changes affect technological breakthrough Reconsidering the prolonged slump of the Japanese economy

This analysis implies that a partial restructuring of the Japanese economy alone cannot achieve recovery from the slump. For example, a governmental structural policy which enhances labor mobility will not achieve recovery without a shake-up in the long-term employment system among highly educated workers, especially in the manufacturing sector, that encourages these highly educated workers to migrate between sectors. Although there has been an increase in labor mobility since the 1990s in Japan, this primarily reflects a decrease in the number of full-time regular employees among the less educated. With regard to government policy which enhances basic research in academic fields, such as through the expansion of graduate schools, this will not stimulate technological progress without a decrease in the proportion of highly educated workers who choose a single-career path. Any new structural policy should take into account the mutual interaction among the manufacturing sector, the service sector, and graduate education, with the aim of encouraging mobility of highly educated workers.

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Studies on Properties of Coir Fibre Reinforced Self Compacting Concrete

Studies on Properties of Coir Fibre Reinforced Self Compacting Concrete

4) The slump flow reduction at the fibre content of 1.5% is due to the resistance of the fibre to the flow of the cement matrix. Visually it shows that, the matrix especially finer portions (i.e., Sand+ Cement + Fly ash) are separated from the fibre content. This tendency is because of less quantity of finer portions as compared to the fibre content. Hence there is a revision of mix proportions is required to get a good flow of matrix

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Study on the behavior of self  compacting concrete with fly ash and glass powder  as partial replacements  for cement

Study on the behavior of self compacting concrete with fly ash and glass powder as partial replacements for cement

215 Tables 3 and 4 represents the quantity of the constituent material for replacements with fly ash (FA) and glass powder (GS). Table 5 gives the fresh state properties and table 6 the compressive strength at 7 and 28 days. Figures 4, 5, 6 and 7 shows the slump flow, V Funnel, L box and 28 day compressive strength gain with replacements of cement by fly ash and glass powder. CM stands for control mix. FA10 represents replacing 10% of cement by fly ash and so on. As a trial replacement by glass powder, FA 30, 30% replacement of cement by fly ash, is selected for again replacing with glass powder as it gave comparatively good result in fresh and hardened properties with minimum admixture and no reduction in expected target strength.

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Modeling of Concrete Slump and Compressive Strength using ANN

Modeling of Concrete Slump and Compressive Strength using ANN

Abstract: Artificial Neural Network (ANN) is a subdivision of Artificial Intelligence are extensively used to answer a complex civil engineering concerns. The following paper would predict the compressive strength and slump, having several mixtures with 28 days. ANN model with 7 different parameters that comprises: Slag (SL), Fly Ash (FL), Fine Aggregate (FA), Coarse Aggregate (CA), Super Plasticizers (SP), Cement (C), Water (W) respectively as input while concrete slump and while compressive strength as output. The same inputs are provided and are developed as another model. The slump and compressive strength of concrete are determined by ANN through its machine learning which is identified by validation, testing and training results. This kind of strength conjecture will help the concrete factories that manufactures the concrete, which when used in concrete will result in definite strength.

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Self Compacting Concrete By Partial Replacement Of Cement With Fly Ash & Coarse Aggregate With Recycled Coarse Aggregate

Self Compacting Concrete By Partial Replacement Of Cement With Fly Ash & Coarse Aggregate With Recycled Coarse Aggregate

About 6 liter of concrete is needed to perform the test, sampled normally. Moisten the base plate and inside of slump cone. Place base-plate on level stable ground. Place the J-ring centrally on the base plate and the slump-cone centrally inside it and hold down firmly. Fill the cone with the scoop. Do not tamp, simply strike off the concrete level with the top of the cone with the trowel. Remove any surplus concrete from around the base of the cone. Raise the cone vertically. and allow the concrete to flow through the ring. Lay the tamping rod with the flat side on the top side of the J-ring and measure the relative height differences between the lower edge of the straight rod and the concrete surface at the central position (∆h 0 ) and at the four

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Sub-seasonal thaw slump mass wasting is not consistently energy limited at the landscape scale

Sub-seasonal thaw slump mass wasting is not consistently energy limited at the landscape scale

Thaw slumps are shaped by thermal, hydrological and me- chanical processes over their entire life cycle from initia- tion to stabilization. Once initiated, active thaw slumps can grow upslope by several metres per year (Lantuit and Pol- lard, 2008) as the headwall retreats into the upslope terrain (Fig. 1). Headwall retreat is linked to energy flux (Lewkow- icz, 1987) and processes in the scar zone. The mass wasting at the headwall releases meltwater and sediment, which ac- cumulates at the base of the headwall as a saturated slurry and must be removed via downslope fluidized flow in order for backwasting to proceed unabatedly (Kokelj et al., 2015). If accumulated material insulates the ice-rich permafrost or if the head scarp retreats into ice-poor terrain, the thaw slump can stabilize (Lacelle et al., 2015). The accumulation and transport of sediment are coupled to the hydrological condi- tions, as meltwater and thawing debris typically form a sat- urated slurry in the slump scar zone (Burn and Lewkowicz, 1990). Depending on the water content, the sediment input and the slope and material properties, this can be a zone of net accumulation or of net volume loss. Net accumulation occurs when the sediments cannot be removed sufficiently quickly: close to the headwall, buttresses of accumulated ma- terial can protect the ground ice and reduce retreat rates (La- celle et al., 2015). Conversely, downslope removal of thawed material at the foot of the headwall can accelerate retreat by exposing ice-rich soil and by increasing the local relief (Kokelj et al., 2015). Thermal processes in the scar zone can also help sustain thaw slump activity by effecting height losses, which are caused by the melting of ground ice in the warm scar zone (Burn, 2000). Many of these same processes that reinforce mass wasting are also central to re-initiating thaw slump activity within stabilized slumps (Kokelj et al., 2009). Such slumps are called polycyclic, as re-initiation re- sults in the formation of a new, actively ablating headwall.

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Increasing coastal slump activity impacts the release of sediment and organic carbon into the Arctic Ocean

Increasing coastal slump activity impacts the release of sediment and organic carbon into the Arctic Ocean

Most of the material and OC mobilized through slump- ing are transported to the nearshore zone (Vonk et al., 2012). However, a fraction of this material and OC remains in the slump floor for several years (Tanski et al., 2017; Obu et al., 2016) where it degrades and is mineralized by microorgan- isms. Hence, OC is mobilized in RTSs prior to its release to the ocean, which modifies the amount of OC available to the coastal ecosystem (Tanski et al., 2017; Cassidy et al., 2016; Pizano et al., 2014). Tanski et al. (2017) show that SOC and DOC decrease by 77 and 55 %, respectively, before reaching the nearshore zone. Abbott and Jones (2015) describe simi- lar processes for RTSs in upland areas: after RTSs develop, 51 % of organic-layer SOC and 21 kg m −2 of mineral-layer SOC is removed. Following headwall erosion, water trans- ports melted ground ice and most sediments to the nearshore zone. Without enough viscous flow, the remaining part of the

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The Post Crisis Slump in the Euro Area and the US

The Post Crisis Slump in the Euro Area and the US

ABSTRACT: This note discusses the drivers of the persistent post-crisis slump in the Euro Area (EA) and the US, and it gives a brief overview of the research literature that studies the slump. The note argues that financial shocks were key determinants of the 2008-09 Great Recession, for both the EA and the US. The post-2009 slump in the EA mainly reflects a combination of adverse aggregate demand and supply shocks, in particular lower productivity growth, and persistent adverse shocks to capital investment, linked to the poor health of the EA financial system. Adverse financial shocks were less persistent for the US.

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Product Development Of Semi Automatic Slump Test

Product Development Of Semi Automatic Slump Test

The slump cone is placed on the base plate of the lifter and filled in the normal method. Semi automatic slump test is a need for constructions field to get a reliable measurement test result and to improve the old design to have an ease of handling personality. This paper is based on the problems that occur from unreliable measurement test result of a manual concrete slump test. Another problem that can occur is that operators lift the cone sideways, as well as upwards during the test, causing the concrete to slump sideways. It can only prevent such as misdiagnosis of the situation by recognizing that slump changes with time. Perhaps one of the most effective, high-tech accessories for improving the precision of slump testing is a wristwatch.

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Product Development Of Semi Automatic Slump Test

Product Development Of Semi Automatic Slump Test

The slump cone is placed on the base plate of the lifter and filled in the normal method. Semi automatic slump test is a need for constructions field to get a reliable measurement test result and to improve the old design to have an ease of handling personality. This paper is based on the problems that occur from unreliable measurement test result of a manual concrete slump test. Another problem that can occur is that operators lift the cone sideways, as well as upwards during the test, causing the concrete to slump sideways. It can only prevent such as misdiagnosis of the situation by recognizing that slump changes with time. Perhaps one of the most effective, high-tech accessories for improving the precision of slump testing is a wristwatch.

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Lateral Pressures of Fresh Concrete on Wall Formwork under High Rates of Placement

Lateral Pressures of Fresh Concrete on Wall Formwork under High Rates of Placement

The results indicated that all of the mixtures exhibited similar lateral pressures initially, approaching full hydrostatic head, but that the rate of decrease of this pressure over time varied greatly with the proportioning of the mixture. Those made with a ternary cement showed a faster reduction in pressure over time than those containing a binary cement. In addition, the presence of a set accelerating admixture also created an increase in this rate of pressure drop over time. The study also found that the rate of pressure drop with time of the different mixtures was independent of the loss of slump flow as measured before placing. They concluded that the time dependent drop in lateral pressure of self-consolidating concrete cannot simply be predicted by the degree of loss of slump flow, but rather is a function of the type of cement and admixtures used in the batching of the concrete mixture (Assaad et al., 2003).

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Effect Of Waste Marble Powder Replacement On Workability Of Self Compacting Concrete

Effect Of Waste Marble Powder Replacement On Workability Of Self Compacting Concrete

highly flowable, non-segregating concrete mix that can be placed even in the most congested reinforcement by means of its own weight, with little or no vibrations. An experimental study was undertaken to study the properties of self- compacting concrete (SCC) in plastic state. In the present study, the waste marble powder (WMP), finer than 4.75 mm were used for the replacement of fine-aggregate. The replacement is done partially in the proportion of 0%, 10%, 20%, 30%, 40%, 50% and its effect on workability of self- compacting concrete were investigated. The workability tests of self-compacting concrete used in this research were the slump flow test, T 50cm slump flow, V-funnel test, J-ring test, L-

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Experimental Investigation on Self Compacting Concrete by Introducing Fly Ash with Varied Size of Aggregate

Experimental Investigation on Self Compacting Concrete by Introducing Fly Ash with Varied Size of Aggregate

Graph -3: Results of Inverted Slump Flow Test Graph represents the inverted slump flow test results showing the ability of filling, with a very high ability of filling at 0%CASCC and very low ability of filling at 50%CASCC. Also it is found that all percentage of coarse aggregates is within the standard limit.

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The Post Crisis Slump

The Post Crisis Slump

The global financial crisis of 2007-09 triggered a sharp fall in output growth that was followed by a persistent slump in Europe and other advanced economies. Almost a decade after the outbreak of the global financial crisis, the recovery remains very weak in many major advanced economies. This special issue of the European Economic Review consists of eleven papers that offer novel empirical and theoretical perspectives on the persistent post-crisis slump and on resulting challenges for global monetary and fiscal policies. All papers were presented at a conference at the European Commission in Brussels on 1-2 October 2015, organized by the European Economic Review, the European Commission, CAEPR, Indiana University and

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Just the Facts: Demographic and Cross Country Dimensions of the Employment Slump

Just the Facts: Demographic and Cross Country Dimensions of the Employment Slump

A variety of non-demographic explanations for the U.S. employment slump have been advanced. We divide them into two broad categories and briefly note their potential policy implications. Our first broad category includes macroeconomic factors associated with business cycles. DeLong and Summers (2012), for example, emphasize the poten- tial role of “hysteresis” effects through which a severe downturn may have sustained, negative impacts on an economy’s performance. To the extent to which such forces are at work, stimulus-oriented policies may be an appropriate response. Baker et al. (2013) present evidence that the Great Recession was coupled with sustained, elevated levels of policy uncertainty, which other work has linked directly to macroeconomic performance (Bloom, 2009; Shoag and Veuger, 2014). From a policy perspective, the “solution” to such uncertainties may simply be to cease with uncertainty generating policy making. 8

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Drivers of the Post Crisis Slump in the Eurozone and the US

Drivers of the Post Crisis Slump in the Eurozone and the US

The global financial crisis (2008-09) led to a sharp contraction in both Eurozone and US real activity, and was followed by a long-lasting slump. However, the post-crisis adjustment in the Eurozone and the US shows striking differences. In particular, the Eurozone slump has been markedly more protracted. There is a heated debate about the causes of these developments. Understanding these causes is essential for an effective policy response to the post-crisis slump.

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An Experimental Study on Rubberized Concrete

An Experimental Study on Rubberized Concrete

important bearing on the building sector. Several attempts have been therefore made in the building material industry to put to use waste material products, e.g., worn-out tyres, into useful and cost effective items. Success in this regard will contribute to the reduction of waste material dumping problems by utilizing the waste materials as raw material for other products. The present proposal involves a comprehensive laboratory study for the newer application of this waste material in the preparation of fibrous concrete. The primary objective of investigation is to study the strength behaviour i.e. compressive and flexural strength, and impact resistance of rubberized concrete with different volume of crumb rubber. Parameter to be varied in Investigation: I. Volume variation of crumb rubber. The proposed work is aimed to study the effect of volume variation of crumb rubber on the compressive strength, flexural strength, split tensile strength Slump test & The relationship between stress and strain of the concrete.

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Deciphering the sophomore slump: changes to student perceptions during the undergraduate journey

Deciphering the sophomore slump: changes to student perceptions during the undergraduate journey

or upper-second class), versus 36% and 46%, respectively, in years one and three (Yorke 2015). If of sufficient scale, a second year slump might compromise degree classification, irrespective of resurgent performance during following year(s). Longitudinal research suggests that many students can progressively improve performance (e.g. GPA) over the course of studies (Mabel and Britton 2018). Consequently, even stable performance between years one and two could reflect suboptimal student progress (Yorke 2015). Previous research indicated that a second year slump in marks occurred in around one quarter of programmes, without specifying the magnitude (Yorke and Zaitseva 2013).

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Improved Concrete Properties Using Quarry Dust as Replacement for Natural Sand

Improved Concrete Properties Using Quarry Dust as Replacement for Natural Sand

The workability is one of the physical parameters of concrete which affects the strength and durability and the appearance of the finished surface. The workability of concrete depends on the water cement ratio and the water absorption capacity if the aggregates. If the water added is more which will lead to bleeding or segregation of aggregates. The test for the workability of concrete is given by the Indian Standard IS 1199-1959 which gives the test procedure using various equipments. In our case we have used slump cone test for measuring the workability of concrete. We have measured the height of the fall of the cone of concrete for various water-cement ratios and recorded the values for ordinary concrete. Then the same procedure is done with the concrete having the partial replacement of sand with raw quarry dust at various percentages. (Fig 4)

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