What to eat to help improve your eyesight Don't just think taste, think eyes too.

Chances are that your grandparents never had to buy a pair of glasses and continued to read the paper and sew buttons on the shirts minus any appendages (spectacles, contacts, laser…) their entire lifetime. Your parents probably needed help in their 60s or so, and for us, well, late 30s or early 40s is quite likely the average age when an eye test usually tells us that our sight is dipping below optimum. And by the looks of it Gen Now seems to be facing these eyesight blues another decade earlier - yes, often in their late 20s.

What's going on?

While our technology dependence and obsession is definitely responsible for this continuous degradation, and genetic propensity has a huge say too, how and what we eat also deeply impact our eyes' health, and so alterations there can definitely help control (at least delay) all eye-related problems like dimming eye sight, age related macular degeneration (ARMG) and even cataracts and the like. This I think is actually good news. 'Coz try taking away the iPad from adults and children alike, and chances are you'll be ticked off categorically. Plates on the other hand can still be tailored differently with a little effort and right information. And right info by the way is far more expansive than just chomping carrots daily.

A cataract-affected eye.

Let's tackle ARMG first

This apparently is the leading cause of blindness today. While oxidation and inflammation of the eyes is responsible very often, there is clear evidence now that foods rich in the antioxidants lutein and zeaxanthin can help reduce the risk substantially. These nutrients also help protect the eyes from harmful ultraviolet light waves and research shows that people with diets high in foods rich in zeaxanthin are up to 50 per cent less likely to develop cataracts too. Luckily these are easy to score. Kale is a super rich source, so is broccoli but as both are acquired tastes and not that easily available too, my advice is to adopt corn with a vengeance. Interestingly some research has shown that cooking actually increases the amount of lutein levels in corn, so go on add it to soups, and casseroles. Ditto for spinach, a leafy green we take much for granted. If you like fruits, then kiwi and grapes should be your go to munchies. And you'd be surprised but basil leaves also give us both these antioxidants, so chew some everyday. Lower ARMG rates are also is linked to higher circulating blood levels of EPA and DHA - essential omega 3 fatty acids found in salmon and other fatty fish. So fix your fish eating days, or chomp some walnuts and flax seeds as they provide ALA, a type of omega 3 which gets converted into EPA and DHA in the body. Salmon in particular also provides another antioxidant astaxanthin, which also provides protection against a number of eye diseases, including blindness.

Next let's talk about eggs

Again panned unnecessarily as being unhealthy for so long, the best thing about this food is actually the yolk, as this yellow goodness is packed not just with lutein but also with other sight friendly nutrients like omega 3, vitamin E and zinc too. E has a role in preventing cataracts (can also get it from almonds, wheat germ, seeds) and zinc enables vitamin A to create a pigment called melanin, which protects the eye. Besides egg, you can get zinc from wheat germ and cashews.

Score enough vitamin C rich too

C helps improve the health of our eye tissue, according to the oft-quoted and referred to expansive age-related eye diseases study. Plus as a bonus it also helps regenerate other important eye friendly antioxidants like vitamin E.

Don't neglect B and A

There are some reports where vitamin B1 deficiency has been linked to vision trouble, so incorporating sunflower seeds, fish and peas is a good idea. And here we must of course talk about bugs bunny favourite carrots. It's actually beta carotene (a kind of vitamin A) in this orange hued food (and also pumpkin and sweet potato) which helps retina and other parts of the eye function smoothly.

Finally…

A diet that's low in trans and saturated fat is not just great for our heart, it is also important to keep the blood vessels of the eyes healthy, so omit margarine and chips from that grocery list please (and excess fried food too). Don't just think taste, think eyes too.

Phones affect Brain Activities

The population researches lead into conclusion of finding about the mobile phone usage that may cause brain cancer. The latest research reveals that the energy emitting from mobile devices can affect brain activities regularly.

The population researches lead into conclusion of finding about the mobile phone usage that may cause brain cancer. The latest research reveals that the energy emitting from mobile devices can affect brain activities regularly.

Someone holding mobiles closed to the ears for a long period of time, really that cause to the antenna, researchers revealed.

Additional studies established that the areas anticipated having the highest engagement of radiofrequency and electromagnetic arenas from cell phone use were really the ones that presented the higher growths in glucose breakdown.

The properties on neuronal action could be cause to variations in neuro transmitter release, cell membrane absorptivity, cell moodiness, or calcium efflux.

It’s also been hypothesized that hotness from mobile phones can pay to practical brain variations, but that is perhaps less probable to be the case, the researchers supposed.

QUANTITY OF CEMENT & SAND CALCULATION IN MORTAR

Quantity of cement mortar is required for rate analysis of brickwork and plaster or estimation of masonry work for a building or structure. Cement mortar is used in various proportions, i.e. 1:1, 1:2, 1:3, 1:4, 1:6, 1:8 etc.

Calculation of quantity of cement mortar in brickwork and plaster:

For the calculation of cement mortar, let us assume that we use 1m3 of cement mortar. Procedure for calculation is:

1. Calculate the dry volume of materials required for 1m3 cement mortar. Considering voids in sands, we assume that materials consists of 60% voids. That is, for 1m3 of wet cement mortar, 1.6m3 of materials are required.

2. Now we calculate the volume of materials used in cement mortar based on its proportions.

Let’s say, the proportion of cement and sand in mortar is 1:X, where X is the volume of sand required.

Then, the volume of sand required for 1:X proportion of 1m3 cement mortar will be

3. Volume of cement will be calculated as:

Since the volume of 1 bag of cement is 0.0347 m3, so the number of bag of cement will be calculated as:

Example:

For cement mortar of 1:6, the quantity calculated will be as below:

Sand quantity:

Quantity of cement (in bags):

Volume of cement = 

There number of bags required =  = 6.58 bags.

QUANTITY & RATE ANALYSIS FOR REINFORCED CONCRETE

Today we will see how to prepare rate analysis for Reinforced Concrete (RCC) work. First step to rate analysis is the estimation of labour, materials, equipments and miscellaneous items for particular quantity of reinforced concrete.

The second step is to determine the component of structure for which the RCC rate analysis is required, as the quantity of reinforcement steel varies with slabs, beams, columns, foundation, RCC Roads etc., though the quantity of other materials like sand, coarse aggregate and cement remain the same with the same mix design (mix proportion) of concrete. Labour rates for reinforcement work changes with type of structural component as the quantity of reinforcement steel changes. The Quantity of materials like sand, cement and coarse aggregates vary with mix design such as M15 (1:2:4), M20 (1:1.5:3), M25, M30 etc..

Here we will see the rate analysis for 1m3 of reinforced concrete.

Data required for RCC Rate Analysis:

1. Estimation of materials:

Material estimation include sand, cement, coarse aggregate and steel for a particular mix design. Let us consider a mix design of 1:1.5:3 for our estimation practice. The dry volume of total materials required is considered as 1.54 times the wet volume of concrete, due to voids present in sand and aggregates in dry stage. Therefore, for our calculation, we will consider the total volume of materials required as 1.54 m3 for 1 m3 of wet concrete.

a) Bags of cement required:

Volume of cement required for 1m3 of Concrete =

=0.28 m3

Then number of bags of cement (volume of one bag of cement = 0.0347 m3)

== 8.07 bags of cement.

b) Volume of Sand required:

Volume of sand required =  = 0.42 m3 of sand.

c) Volume of Coarse Aggregate Required

Volume of Coarse Aggregate == 0.84 m3 of coarse aggregates.

d) Estimation of Reinforced Steel:

Quantity of steel required depends on components of structure, i.e. slabs, beams, columns, foundations, roads etc. To estimate the steel required, there are two methods.

First method is, when we have the drawing available, we can calculate the total weight of steel required divided by total volume of concrete for different components. This will give us the weight of reinforcement steel per cubic meter of concrete.

Second method is assuming the percentage of reinforcement for different components. Following are the percentage of reinforcement steel generally required per different components. Its values can vary from structure to structure, and can be assumed from past experiences of similar structure.

• For slabs = 1.0 % of concrete volume.
• For Beam = 2 % concrete volume.
• For column = 2.5 % of concrete volume.
• For RCC Roads, 0.6% concrete volume.

Lets take example of RCC Column, where reinforcement required is 2.5% of concrete volume, weight of steel required will be:

=196.25 kg.

2. Labour Requirement for 1m3 of RCC:

Labours required are presented in terms of days required by particular labour to complete its work for the given quantity of concrete. Following are the various labours required:

a) Mason: As per Standard Schedule of Rates and Analysis of Rates, One mason is required for 0.37 days.

b) Labours: One Unskilled labours required for 3.5 days.

c) Water carrier: One water carrier required for 1.39 days.

d) Bar Bender: Bar bender requirement depends on weight of reinforcement. Lets consider one bar bender required for 100 kg of steel as for 1 day.

e) Mixer Operator: One mixer operator required for 0.0714 days.

f) Vibrator Operator: One vibrator operator required for 0.0714 days.

3. Equipments and sundries:

Equipment and other charges, such as water charges, miscellaneous items, tools and tackles etc can be assumed as some percentage of total cost of materials and labours. Lets say it as 7.5%.

4. Contractor’s Profit:

Contractor’s profit depends on place to place, organization to organization and work to work. It varies from 10 – 20%. For our case lets assume it as 15% of total cost of materials, labours and equipments.

We have calculated the quantity of every item in above 1 – 3 steps. For rate analysis of RCC, we need to multiply each quantity with their rates to get the amount for every item of work. Rates vary from place to place and time to time. It is advisable to assume local rates or standard rates of the place.

The sum total of all the four items above will give the rate or cost for 1m3 of concrete.

DOWNLOAD: RCC Rate Analysis Spreadsheet

COMPRESSIVE STRENGTH OF CONCRETE CUBES

Compressive strength of concrete: Out of many test applied to the concrete, this is the utmost important which gives an idea about all the characteristics of concrete. By this single test one judge that whether Concreting has been done properly or not.

For cube test two types of specimens either cubes of 15 cm X 15 cm X 15 cm or 10cm X 10 cm x 10 cm depending upon the size of aggregate are used. For most of the works cubical moulds of size 15 cm x 15cm x 15 cm are commonly used.

This concrete is poured in the mould and tempered properly so as not to have any voids. After 24 hours these moulds are removed and test specimens are put in water for curing. The top surface of these specimen should be made even and smooth. This is done by putting cement paste and spreading smoothly on whole area of specimen.

These specimens are tested by compression testing machine after 7 days curing or 28 days curing. Load should be applied gradually at the rate of 140 kg/cm2 per minute till the Specimens fails. Load at the failure divided by area of specimen gives the compressive strength of concrete.

Following are the procedure for Compressive strength test of Concrete Cubes

APPARATUS

Compression testing machine

PREPARATION OF CUBE SPECIMENS

The proportion and material for making these test specimens are from the same concrete used in the field.

SPECIMEN

6 cubes of 15 cm size Mix. M15 or above

MIXING

Mix the concrete either by hand or in a laboratory batch mixer

HAND MIXING

(i)Mix the cement and fine aggregate on a water tight none-absorbent platform until the mixture is thoroughly blended and is of uniform color

(ii)Add the coarse aggregate and mix with cement and fine aggregate until the coarse aggregate is uniformly distributed throughout the batch

(iii)Add water and mix it until the concrete appears to be homogeneous and of the desired consistency

SAMPLING

(i) Clean the mounds and apply oil

(ii) Fill the concrete in the molds in layers approximately 5cm thick

(iii) Compact each layer with not less than 35strokes per layer using a tamping rod (steel bar 16mm diameter and 60cm long, bullet pointed at lower end)

(iv) Level the top surface and smoothen it with a trowel

CURING

The test specimens are stored in moist air for 24hours and after this period the specimens are marked and removed from the molds and kept submerged in clear fresh water until taken out prior to test.

PRECAUTIONS

The water for curing should be tested every 7days and the temperature of water must be at 27+-2oC.

PROCEDURE

(I) Remove the specimen from water after specified curing time and wipe out excess water from the surface.

(II) Take the dimension of the specimen to the nearest 0.2m

(III) Clean the bearing surface of the testing machine

(IV) Place the specimen in the machine in such a manner that the load shall be applied to the opposite sides of the cube cast.

(V) Align the specimen centrally on the base plate of the machine.

(VI) Rotate the movable portion gently by hand so that it touches the top surface of the specimen.

(VII) Apply the load gradually without shock and continuously at the rate of 140kg/cm2/minute till the specimen fails

(VIII) Record the maximum load and note any unusual features in the type of failure.

NOTE

Minimum three specimens should be tested at each selected age. If strength of any specimen varies by more than 15 per cent of average strength, results of such specimen should be rejected. Average of there specimens gives the crushing strength of concrete. The strength requirements of concrete.

CALCULATIONS

Size of the cube =15cm x15cm x15cm

Area of the specimen (calculated from the mean size of the specimen )=225cm2

Characteristic compressive strength(f ck)at 7 days =

Expected maximum load =fck x area x f.s

Range to be selected is …………………..

Similar calculation should be done for 28 day compressive strength

Maximum load applied =……….tones = ………….N

Compressive strength = (Load in N/ Area in mm2)=……………N/mm2

=……………………….N/mm2

REPORT

a) Identification mark

b) Date of test

c) Age of specimen

d) Curing conditions, including date of manufacture of specimen

f) Appearance of fractured faces of concrete and the type of fracture if they are unusual

RESULT

Average compressive strength of the concrete cube = ………….N/ mm2 (at 7 days)

Average compressive strength of the concrete cube =………. N/mm2 (at 28 days)

Percentage strength of concrete at various ages:

The strength of concrete increases with age. Table shows the strength of concrete at different ages in comparison with the strength at 28 days after casting.

Age	Strength per cent
1 day	16%
3 days	40%
7 days	65%
14 days	90%
28 days	99%

Compressive strength of different grades of concrete at 7 and 28 days

Grade of Concrete	Minimum compressive strength N/mm2 at 7 days	Specified characteristic compressive strength (N/mm2) at 28 days
M15	10	15
M20	13.5	20
M25	17	25
M30	20	30
M35	23.5	35
M40	27	40
M45	30	45