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What is the difference between DCP test and CBR test?
DevilAVRT
Dynamic Cone Penetration testing DCP testing is utilized to decide the quality of the subsurface and configuration heap of the dirt. The designers play out the testing in-situ to give an estimation of the heap bearing limit which a clay can withstand, by estimating the degree of infiltration into thRead more
Dynamic Cone Penetration testing
DCP testing is utilized to decide the quality of the subsurface and configuration heap of the dirt. The designers play out the testing in-situ to give an estimation of the heap bearing limit which a clay can withstand, by estimating the degree of infiltration into the ground of an aligned tip or cone. Stiffer soils will yield a lower infiltration rate while gentler soils will bring about the expanded entrance.
When the most extreme structure heap of dirt is known, these outcomes can be utilized to figure-fitting footings and establishments for sub/superstructures to be put on or inside the dirt. All DCP tests are performed by ADE’s group of geotechnical designs and agree to AS1289.6.3.2 and AS1289.6.3.3.
Californian Bearing Ratio testing
CBR testing is led to decide the quality of a material (normally a subgrade) when it is at its greatest compaction. This reason for this is to decide the necessary thickness of a basic layer or asphaltic layer (for example, a pathway) to be put on the head of the tried material. This test guarantees that the quality necessities sketched out by the extent of works are fulfilled.
To play out this test, the greatest dry thickness is required to be embraced on the preceding material testing to decide the remolded thickness of the example. The example is normally remolded at 100% of standard compaction (or the relative compaction accomplished nearby) to decide the quality of the material. This test will require the time taken for a most extreme dry thickness to be embraced, and afterward, a multi-day drench to decide the reactivity of the dirt preceding testing.
This worth is given as a rate when contrasted with a normalized material (California Limestone) where a low worth relates to powerless fill and a high incentive to solid filling.
What is full form of SP in Indian standard code?
DevilAVRT
Special Publications
Special Publications
What could be the possible pros and cons of using beach sand instead of river sand in concrete mix for structural members?
DevilAVRT
It may contain salt. So later it will result in shrinkage and cracking. And it will also not result in same strength as river sand gives. Definitely the salts adsorbed (dissolution might not actually occur) on the sand are going to affect the durability in reinforced concrete structures but in plainRead more
It may contain salt. So later it will result in shrinkage and cracking. And it will also not result in same strength as river sand gives.
Definitely the salts adsorbed (dissolution might not actually occur) on the sand are going to affect the durability in reinforced concrete structures but in plain concrete or mortar for plaster, it might not be that detrimental. It is not that hard to get rid of salts adhered to sand particles.
However, apart from salts, there are several factors that hinder its use, like aggregate shape and size. Sea sand, generally tends to very fine and rounded, which is not particularly advisable when designing mixes. A kind of blending is required with coarse and angular aggregate to develop the rheology and microstructure desired.
However, when the economy demands, it is used. Practically speaking, the aggregates are good to use as long as they are in compliance with respective codes of practice (like ASTM C33). If the aggregates make it through all the tests and clauses, then you can officially use the material in construction.
Edit: The possibility of the use of crushed gravel.
Crushed gravel would be siliceous in nature and could be a decent alternative. However, the process could be slightly demanding, since crushing operations are usually performed on larger boulders to “crush” them to required sizes and distribute for use.
There could also be an issue of salts. In my post, I said that they could be physically removed, which might not be completely true.
You see the water (which usually has dissolved salts) that is present will be absorbed (absorption capacity of aggregate) and in the process, the salts may get deposited in the porous microstructure of the aggregate, which ultimately cannot be removed by physical treatment completely.
So a careful investigation is recommended that is more than just tests on aggregate since the combination of water (in concrete) might release the salts back into solution.
See lessWhat are the functions of earth retaining walls, boundary walls, load-bearing walls, and non-load-bearing walls?
DevilAVRT
Functions of earth retaining walls Flexibility to accommodate high differential settlement and several feet of total settlement Bearing pressure is distributed over a wide foundation area Extreme wall heights can be achieved Extreme loads can be carried (bridge abutment footings, cranes) High resistRead more
Functions of earth retaining walls
Functions of load bearing walls
Functions of non-load bearing walls
Why is Traverse Surveying used in Road Projects?
DevilAVRT
Generally, there are two types of traverse surveys. Open and closed traverse. And we can use open traverse for road construction. Open traverse surveys may extend for long distances without the opportunity to check the accuracy of the ongoing work. That's why we can use and prefer open traverse
Generally, there are two types of traverse surveys.
Open and closed traverse.
And we can use open traverse for road construction.
Open traverse surveys may extend for long distances without the opportunity to check the accuracy of the ongoing work. That’s why we can use and prefer open traverse
See lessWhich type of soil is present in desert?
DevilAVRT
Most desert soils are called Aridisols (dry soil). However, in really dry regions of the Sahara and Australian outback, the soil orders are called Entisols. Entisols are new soils, like sand dunes, which are too dry for any major soil horizon development. Most desert soils are called Aridisols (dryRead more
Most desert soils are called Aridisols (dry soil). However, in really dry regions of the Sahara and Australian outback, the soil orders are called Entisols. Entisols are new soils, like sand dunes, which are too dry for any major soil horizon development.
Most desert soils are called Aridisols (dry soil).
What is spirit leveling in survey work?
DevilAVRT
If you are talking about spirit level, then it is an instrument used to level the apparatus of surveying vertically. There is liquid in it with a bubble. It is present on every apparatus of surveying. But if you are talking about spirit leveling, then it was a method for calculating elevation.
If you are talking about spirit level, then it is an instrument used to level the apparatus of surveying vertically. There is liquid in it with a bubble. It is present on every apparatus of surveying.
But if you are talking about spirit leveling, then it was a method for calculating elevation.
See lessHow Gibbs module outlet work in the canal outlet system?
DevilAVRT
Gibb's Rigid Module Gibb's module has an inlet pipe below the distributary bank. The pipe takes water from the distributary to a rising spiral, which is connected to the eddy chamber. This produces free vortex motion owing to which there is heading up of water (due to smaller velocity at larger radiRead more
Gibb’s Rigid Module
Gibb’s module has an inlet pipe below the distributary bank. The pipe takes water from the distributary to a rising spiral, which is connected to the eddy chamber. This produces free vortex motion owing to which there is heading up of water (due to smaller velocity at larger radius – a feature of vortex motion) near the outer wall of the rising pipe. The water surface thus slopes towards the inner wall. A series of baffle plates of appropriate size are attached to the roof of the eddy chamber such that their lower ends slope against the direction of flow. As the head increases, water banks up at the outer wall at the eddy chamber and strikes against the baffles and spins round in the compartment between two adjacent baffle plates. This results in the dissipation of excess energy an2 release of a constant discharge. The outlet is relatively more expensive, and its sediment withdrawing characteristic is also not good.
The following discharge formula was given by Gibbs:
Q = ro √2g (d1 + ho)1.5 [(m2 – 1)/m3 x loge m + 1/m loge m – (m2 – 1)/2m2]
where Q = discharge passing down the module,
ro = radius of the outer semicircle of the eddy chamber,
m = ro/ r1 = ratio of outer radius to inner radius,
r1 = radius of inner semicircle,
d1 = depth of water at inner circumference,
ho = head loss in inlet pipe.
The formula is based on the free vortex flow in which the velocity at any point varies inversely as the radius, and by Bernoulli’s theorem, the total energy of all filaments is constant. Gibb’s formula holds good only for his standard design in which m or (r0/r1) = 2 and (ho/D) = 1/7, where D is the difference of level measured from the minimum water level in the parent channel to the floor of eddy chamber.
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