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CONSTRUCTION LAB REPORT: Concrete Mixing

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  CONSTRUCTION LAB REPORT Concrete Mixing Summary: This blog post is a report of laboratory concrete mixture, followed by a slump test to ensure good workability of the concrete. Introduction: Concrete is a mixture of cement, sand, aggregate, water, and possibly an admixture. Proportions of each ingredient are adjusted to produce a well-balanced mix. Concrete sets in as few as 10 hours and continues to harden and cure as long as moisture and unhydrated cement are present. However, most of the increase in strength occurs within a few weeks. Experimental Procedure: 1.     For strength requirements, select the water to cement ratio by weight. 2.     Before mixing concrete, be sure that the mixer has been "buttered" with a mixture of cement, sand, and water. 3.     Divide your water into two buckets, one with about 3/4 of the water. 4.     Put about half the coarse aggregate and the 3/4-bucket of water. 5.     Start the mixer. 6.     Add about half the f

SOIL REPORT: Consolidation test

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  SOIL REPORT Consolidation test Purpose: This test is performed to determine the magnitude and rate of volume decrease that a laterally confined soil specimen undergoes when subjected to different vertical pressures.  From the measured data, the consolidation curve (pressure-void ratio relationship) can be plotted. This data is useful in determining the compression index, the recompression index, and the preconsolidation pressure (or maximum past pressure) of the soil. In addition, the data obtained can also be used to determine the coefficient of consolidation and the coefficient of secondary compression of the soil.   Significance: The consolidation properties determined from the consolidation test are used to estimate the magnitude and the rate of both primary and secondary consolidation settlement of a structure or an earth fill, used in the design of engineered structures and the evaluation of their performance.   Equipment : Consolidation device (including ring

SOIL REPORT: Hydrometer test

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  SOIL REPORT:  Hydrometer test        Abstract:  This blog post is a report of laboratory soil analysis to determine the grain size of fine-grained soils. Apparatus: ·         Hydrometer made of glass and primarily consists of two parts: o    A cylindrical stem with graduation marks o    A bulb at bottom weighted with mercury ·          Dispersion cup with a mechanical stirrer with complete accessories ·          Two glass jars of 1-liter capacity ·          Deflocculating agent (sodium Hexa metaphosphate solution prepared by dissolving 33g of sodium Hexa metaphosphate and 7g of sodium carbonate in distilled water to make one-liter solution) ·          Stopwatch ·          Thermometer ·          Scale Objective: Hydrometers are designed to give the amount of soil, in grams, that is still in suspension. Measure the relative density of a liquid. Hydrometer analysis is done for grain size analysis of fine-grained soils. The lower the density of the liquid th