Brick is a lot stronger than mortar and can hold heavy objects such as televisions. Mortar should only be drilled if the brick is too fragile and therefore susceptible to cracking.

Mud Bricks If the amount of sticky clay is more, then bricks will develop cracks during drying. Similarly if sand is more, then bricks will become weak. Mud raw bricks are dried slowly in a shade. To make raw mud bricks stronger, grass is mixed in soil and clay is formed.

Class A engineering bricks

Which statement is incorrect? Cavity masonry walls are beneficial because: Their two wythes of brick masonry provide added insulation.

Why are mortar joints tooled? Which tooling profiles are suitable for a brick wall in a severe climate? tooling gives a neat appearance and compact the mortar. Vee joints and concave joints are suitable for severe climate.

The most common types of masonry units are brick, concrete masonry units, and stone.

All traditional mortars are essentially a blend of sand, Portland cement and hydrated lime. These three ingredients are mixed at different proportions depending on the intended use. The 4 main types of mortar most commonly used are; Type N, M, S, and O.

Why is marble or limestone stonework never washed with acid, as brickwork is? Marble and limestone react with acid and are consumed by it.

Acid rain is slowly destroying once-resistant granite. Acid rain is created by air pollutants. The chemicals fall to earth as acid rain. Of all the building stones, granite is the least susceptible to acid rain because its composition is of feldspar and quartz, both of which resist attacks of acid.

When sulfurous, sulfuric, and nitric acids in polluted air and rain react with the calcite in marble and limestone, the calcite dissolves. In exposed areas of buildings and statues, we see roughened surfaces, removal of material, and loss of carved details.

Marble resists acid rain slightly more than limestone because its structure is more densely packed.

When acidic rainwater falls on limestone or chalk, a chemical reaction happens. New, soluble, substances are formed in the reaction. These dissolve in the water, and then are washed away, weathering the rock.

Acid precipitation affects stone primarily in two ways: dissolution and alteration. When sulfurous, sulfuric, and nitric acids in polluted air react with the calcite in marble and limestone, the calcite dissolves. Eventually the black crusts blister and spall off, revealing crumbling stone.

Acid rain damages buildings and structures because it dissolves the stone or corrodes the metal that is exposed to the weather. Before people became aware of the problems that acid rain caused, they often used metals, limestone and marble as building materials exposed to rain and fog.

Acid rain has been shown to have adverse impacts on forests, freshwaters, and soils, killing insect and aquatic life-forms, causing paint to peel, corrosion of steel structures such as bridges, and weathering of stone buildings and statues as well as having impacts on human health.

A great way to reduce acid rain is to produce energy without using fossil fuels. Instead, people can use renewable energy sources, such as solar and wind power. Renewable energy sources help reduce acid rain because they produce much less pollution.

Acid rain is caused by a chemical reaction that begins when compounds like sulfur dioxide and nitrogen oxides are released into the air. These substances can rise very high into the atmosphere, where they mix and react with water, oxygen, and other chemicals to form more acidic pollutants, known as acid rain.

The quick version: Yes, acid rain is still around, and yes it’s still a problem. Rain is naturally slightly acidic, since picks up carbon dioxide in the air, producing carbonic acid. But when it starts absorbing industrial pollutants like sulfur dioxide and nitrogen oxide, the acidity becomes troublesome.

Acid rain can be extremely harmful to forests. Acid rain that seeps into the ground can dissolve nutrients, such as magnesium and calcium, that trees need to be healthy. Acid rain also causes aluminum to be released into the soil, which makes it difficult for trees to take up water.

Various Causes of Air pollution

• The Burning of Fossil Fuels.
• Agricultural Activities.
• Waste in Landfills.
• Exhaust From Factories and Industries.
• Mining Operations.
• Indoor Air Pollution.
• Natural Events.

The combustion of fossil fuels like coal, petroleum and other factory combustibles is a major cause of air pollution. These are generally used in power plants, manufacturing facilities (factories) and waste incinerators, as well as furnaces and other types of fuel-burning heating devices.

10 Serious Effects of Air Pollution on the Environment

• Global Warming.
• Climate Change.
• Acid Rain.
• Smog effect.
• Deterioration of fields.
• Extinction of animal species.
• Respiratory health problems.
• Deterioration in building materials.

Top of the POPs: The world’s most dangerous pollutants

• Dichlorodiphenyltrichloroethane (DDT)
• Polychlorinated biphenyls (PCBs)
• Hexochlorobenzene (HCB)
• Hexachlorocyclohexane.
• Hexabromocyclododecane (HBCD)

Averaged worldwide, anthropogenic aerosols—those made by human activities—currently account for approximately 10 percent of our atmosphere. Increased levels of fine particles in the air are linked to health hazards such as heart disease, altered lung function and lung cancer.

Human activities that are major sources of outdoor air pollution, include:

• Fuel combustion from motor vehicles (e.g. cars and heavy duty vehicles)
• Heat and power generation (e.g. oil and coal power plants and boilers)
• Industrial facilities (e.g. manufacturing factories, mines, and oil refineries)

Air pollution can also cause headaches, dizziness, and nausea. Long-term health effects from air pollution include heart disease, lung cancer, and respiratory diseases such as emphysema. Air pollution can also cause long-term damage to people’s nerves, brain, kidneys, liver, and other organs.