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What is the type of Nozzle used for pelton wheel model
AdityaBhandakkar
Hi, During selecting a penstock, it's a crucial choice of the pipe diameter and the pressure permissible with the material. the material should be selected according to the pressure and the condition of the run also with local circumstances. HDPE- high-density polyethene pipes are a popular choice aRead more
Hi,
During selecting a penstock, it’s a crucial choice of the pipe diameter and the pressure permissible with the material. the material should be selected according to the pressure and the condition of the run also with local circumstances. HDPE- high-density polyethene pipes are a popular choice as a material for penstock. By using this material determine gives efficiency by up to 70%.
Nozzles must be designed in a way that the laws of pressure are as much as small as possible so that the coefficient of nozzle increases. To avoid the friction nozzle should be constructed with a possible largest radius.
See lessWhat is the purpose of doing CBR Test?
Kuldeep Singh
The purpose of doing a CBR test is to find out the California Bearing Ratio (CBR) of a material which has to be used for the subgrade of flexible pavements. The actual quantity that concerns the strength of the subgrade material is Resilient Modulus though. CBR is different from it but hugely corellRead more
The purpose of doing a CBR test is to find out the California Bearing Ratio (CBR) of a material which has to be used for the subgrade of flexible pavements. The actual quantity that concerns the strength of the subgrade material is Resilient Modulus though. CBR is different from it but hugely corellated. Also, in literature there are curves plotted for the CBR against the expected traffic (million axles per year) for every subgrade thickness. We can read the required thickness for which we need to design the subgrade layer if we know the CBR of our material and the design traffic. So, it is preferred not to get into the complexity of resilient modulus calculation and use CBR instead which can be easily tested on site.
By definition, CBR is the ratio of the opposing bearing stress experienced by a standard penetrator when penetrated by a distance of 2.5 cm into the rock to the actual crushing strength of the rock in percentage.
See lessWhat is Kelly ball test for workability of concrete?
AdityaBhandakkar
ASTM C-360 92 introduced the Kelly ball test for measuring the workability of concrete. Kelly ball test: 1) Freshly prepared concrete poured into a 20cm depth container. Make the leveled and remove all voids by shaking. 2)Kept the Kelly ball setup on that stiff paste in such a way that frame touchesRead more
ASTM C-360 92 introduced the Kelly ball test for measuring the workability of concrete.
Kelly ball test:
1) Freshly prepared concrete poured into a 20cm depth container. Make the leveled and remove all voids by shaking.
2)Kept the Kelly ball setup on that stiff paste in such a way that frame touches the paste and hold the handle of the hemisphere.
3)The frame setup kept Min. 23 cm away from circumference of container.i.e kept at the center.
4)Release handle and allow hemisphere to penetrate in the concrete paste.
5)Note down the reading. Do this process three times on different portions and make an average of these values.
See lessHow to conduct a soundness tests on cement?
Nimesh Gajera
The cement considers unsound if it undergoes a large change in volume (expansion) that causes cracking of hardened cement paste when it is under the condition of restraint. Apparatus Required: Le-Chateliers Apparatus, Water bath, Vernier Caliper, Weighing Scale. Procedure : 1. Place the lightly oileRead more
The cement considers unsound if it undergoes a large change in volume (expansion) that causes cracking of hardened cement paste when it is under the condition of restraint.
Apparatus Required: Le-Chateliers Apparatus, Water bath, Vernier Caliper, Weighing Scale.
Procedure :
1. Place the lightly oiled mold on a lightly oiled glass sheet and fill it with cement paste formed by gauging cement with 0.78 times the water required to give a paste of standard consistency.
2. Cover the mold with another piece of lightly oiled glass sheet, place a small weight on this covering glass sheet and immediately submerge the whole assembly in water at a temperature of 27 ± 2°C and keep there for 24 hours.
3. Measure the distance separating the indicator points to the nearest 0.5 mm. Submerge the mold again in water at the temperature prescribed above.
4. Bring the water to boiling, with the mold kept submerged, in 25 to 30 minutes, and keep it boiling for three hours. Remove the mold from the water, allow it to cool, and measure the distance between the indicator points.
5. The difference between these two measurements indicates the expansion of the cement. This must not exceed 10 mm for ordinary, rapid hardening, and low heat Portland cements. If in case the expansion is more than 10 mm as tested above, the cement is said to be unsound.
Observation And Recording:
Soundness/expansion of cement = L1-L2
See lessL1=Measurement taken after 24 hours of immersion in water at a temp. of 27 ± 20C
L2=Measurement taken after 3 hours of immersion in water at boiling temperature.
Calculate the mean of two values to the nearest 0.5 mm.
How to Determine the Specific Gravity of Chemicals using Pycnometer?
Rohan Chaugule
Steps PROCEDURE Clean and dry the density bottle wash the bottle with water and allow it to drain. Wash it with alcohol and drain it to remove water. Wash it with ether, to remove alcohol and drain ether. Weigh the empty bottle with stopper (W1) Take about 10 to 20 gm of oven soil sample which is cRead more
Steps
PROCEDURE
under constant temperature water baths (Tx0 ).
OBSERVATIONS
2
3
4
Weight of density bottle + dry soil (W2 g)
Weight of bottle + dry soil + water at temperature T x0 C (W3 g)
Weight of bottle + water (W4 g) at temperature Tx0 C
INTERPRETATION AND REPORTING
Unless or otherwise specified specific gravity values reported shall be based on water at 270C. So the specific gravity at 270C = K�Sp. gravity at Tx0C.
See lessWhat is gradation limits for 6mm aggregates?
Gopal Mishra
you can refer to this article https://test.theconstructor.org/practical-guide/grading-limits-for-aggregates/2383/
you can refer to this article https://test.theconstructor.org/practical-guide/grading-limits-for-aggregates/2383/
See less