Best answer

There is the gap between railway tracks because in summer due to heat iron expands and thus it replace the gap. But if there is no gap then in summer or in winter due to expandation or comtraction the railway tracks get damaged and thus there may be chance of accidents.

Answered by: cyb3rZ Date created: Jun 23, 2022

Which bridge is stronger concrete or steel?

Asked By: Collin Jackson Date created: Jun 11, 2022

There is no statistical evidence to support that concrete is better than steel. In fact, it has been shown that concrete cracks and has a lower tensile strength than other materials. Conversely, steel does not crack and often sees wear and tear at the joints and bearings, an easy enough fix for construction teams.

Answered By: juzzlin Date created: Jun 12, 2022

Why is my fresh concrete cracking?

Asked By: Nikolas Charalambidis Date created: Jun 21, 2022

There are several reasons why concrete cracks, with the most common being drying shrinkage. Concrete, when placed in the plastic state, is at its largest volume. As the concrete sets and hardens, it begins to shrink. On average, concrete shrinks 1/8 inch in twenty feet.

Answered By: Jonathan Wakely Date created: Jun 24, 2022

Why are iron nails of railway tracks fixed over wide wooden or concrete sleepers?

Asked By: Not_a_Golfer Date created: Jun 17, 2022

Iron rails are fixed over wide wooden or concrete sleepers to reduce pressure received from the train by increasing the area of contact, because if surface area increases pressure decreases and vice-versa, they also transfer the loads to the ground underneath.

Answered By: KingCrunch Date created: Jun 19, 2022

What is the cause of cement shortage?

Asked By: Jon Schneider Date created: Jun 21, 2022

The cement shortage is actually the result of last spring's flooding and some problems at cement plants down south. Cement is the main ingredient, along with aggregates, in making concrete. And there's no replacement for it. It's in our roads and bridges, basements and high rises.

Answered By: chuckj Date created: Jun 24, 2022

Do you have to pour concrete all at once?

Asked By: BlivetWidget Date created: Jun 10, 2022

If you don't pour the whole thing at once, you get cold joints. Cold joints happen when concrete poured into a slab is allowed to partially or completely dry before more concrete is added. Cold joints usually don't look good at all. ... So that won't work for a slab this size.

Answered By: Tatu Ulmanen Date created: Jun 11, 2022

Why is my concrete still soft?

Asked By: Jeff Date created: Jun 09, 2022

There are a few factors which lead toward soft concrete. Excess water is the biggest culprit but we also have to consider the following; poor or insufficient curing, too little cement, carbonation, incorrect proportion of trace ingredients such as pozzolans or shrinkage additives.

Answered By: carl Date created: Jun 10, 2022

Do I need rebar for small concrete slab?

Asked By: Taeeun Kim Date created: Jun 12, 2022

You do not need rebar for any slab if you make it thick enough and space the joints properly. Rebar in jointed pavement is there to counter the cupping effect of thermal expansion. I always recommend the use of rebar or at least rewire. Any concrete slab can crack.

Answered By: Dan Lowe Date created: Jun 15, 2022

Why is my new cement cracking?

Asked By: Hashem Qolami Date created: Jun 13, 2022

There are several reasons why concrete cracks, with the most common being drying shrinkage. Concrete, when placed in the plastic state, is at its largest volume. As the concrete sets and hardens, it begins to shrink. On average, concrete shrinks 1/8 inch in twenty feet.

Answered By: Ma0 Date created: Jun 15, 2022

Are sidewalks made of cement or concrete?

Asked By: gman Date created: Jun 09, 2022

Concrete works well in larger projects, while cement is more often used in smaller jobs. One of the strongest and longest-lasting materials known to man, concrete is used to build schools, bridges, sidewalks, and countless other structures.

Answered By: Don Kirkby Date created: Jun 09, 2022

How do I fill the gap between concrete floor and wall?

Asked By: Aakash Date created: Jun 22, 2022

Once a year, go around your home and fill these gaps and joints with urethane caulk (or polyurethane caulk) to prevent problems. The expansion joint caulk is available at contractor supply stores, well-stocked home centers and hardware stores. For gaps and joints more than 1/4 in.

Answered By: Ned Batchelder Date created: Jun 25, 2022

Related Question Answers

Yahya

Professor

How do you fill gap between cement board and tub?

Technically, after the tile is installed over the backer board that gap between it and the tub ledge should be filled with an ASTM C920 sealant (caulking e.g. silicone). Although some say you should have weep holes along this gap so any water behind can weep out into the tub.

anubhava

Professor

How do you fill gaps between concrete and House?

Fill and smooth the joint Fill the crack with urethane caulk, similar to what you would use for driveway caulk. It works perfectly as a concrete expansion joint sealant. Snip the opening of the tube at a 30-degree angle, making the opening the same size as your gap.

Leo Dabus

Professor

Do you leave a gap between cement board?

Stagger all HardieBacker cement board joints. Do not align with subfloor joints. Never allow all four corners of boards to meet at one point. We recommend an 1/8 in gap between board edges.

sol

Professor

Does plaster insulate?

Insulating plaster is an excellent example of a modern-day plaster. Especially in older homes, there often is little to no insulation in this small gap inside the wall. Gypsum-based plaster does little to block the weather or temperature.

Alan Storm

Professor

Is dental cement permanent?

Very little pulpal irritation is seen with its use due to the large size of the polyacrylic acid molecule. The many uses of this cement include permanent cementation of crowns, bridges, inlays, onlays, and orthodontic appliances.

charlax

Professional

What do dentists use to cement bridges?

Ketac cem plus is a resin-modified glass ionomer cement used for routine cementation of PFM and metal crowns, bridges, inlays/onlays, crowns made with all-alumina or all-zirconia cores.

Adil B

Professional

Why is my Portland cement cracking?

There are two and only two factors which produce all cracking in Portland cement plaster. One is that normal change in volume of Portland cement plaster intrinsic to the hydration and curing of the cement binder and /or the loss of the mix water in excess of the moisture required for hydration.

cletus

Professional

How long does concrete need to cure before rain?

about 12 hoursKeep an eye on the weather forecasts and try to find a gap of at least 12 hours where there is no rain. Fresh concrete needs about 12 hours to start the curing process and any rain could affect this. The wind can also have a negative impact on the curing process.

floatingpurr

Professional

How long should concrete dry before it rains?

about 12 hoursAvoid pouring concrete during heavy rains Keep an eye on the weather forecasts and try to find a gap of at least 12 hours where there is no rain. Fresh concrete needs about 12 hours to start the curing process and any rain could affect this.

geekosaur

Professional

What do you do with a gap between tub and cement board?

Caulk the gap Ideally, you would leave a 1/8 inch gap which would then have the sealant applied to it. Either stopping the cement board above the tub flange or alternately shimming it out and dropping it down near the tub would both be good options.

Constantin

User

Why running on concrete is bad for you?

Hard surfaces cannot absorb the pressure easily and so they reflect that energy back up into your joints.

Concrete is one of the hardest surfaces to run on, which means most of the energy of your footfall is reflected back into your body with each step..

dustin.schultz

User

How long do concrete bridges last?

100 to 150 yearsSome notable concrete bridges have been constructed in the United States in recent years using criteria developed to ensure service life of 100 to 150 years.

gabra

User

What concrete is used for bridges?

The reinforced or the prestressed concrete is used for the construction of bridges. The reinforcement in R.C.C provides the ductility property to the structure.

F_SO_K

User

How far apart should expansion joints be in concrete sidewalk?

Joints are commonly spaced at distances equal to 24 to 30 times the slab thickness. Joint spacing that is greater than 15 feet require the use of load transfer devices (dowels or diamond plates). Contraction joints may be tooled into the concrete surface at the time of placement.

onteria_

User

What is a dry sand and cement mix?

Dry grouting is method of using a dry mix of sand and cement to fill joints in paving, and then rely on natural moisture to hydrate the cement content.

Jin Kim

Guest

Are cold joints in concrete bad?

In General, cold joints in concrete do not create an integrity issue; this is specially true if the structural member is under compression. However, there is a chance that a poor bond between two batches of concrete create a weak zone, with potential voids.

CodesInChaos

Guest

Why is reinforced concrete used in bridges?

Concrete with steel bars embedded in it is called reinforced concrete. Reinforcement allows for less concrete to be used because the steel carries all the tension; also, the concrete protects the steel from corrosion and fire. Where is the longest bridge?

bodacydo

Guest

Are there concrete houses in the US?

Second, people CAN build concrete homes in the United States, and they DO. But there are a lot of reasons why there are not very many concrete homes here. Again, they have to do with economics, material availability, climate, etc.

Sep Roland

Guest

Can a concrete structure be completely free of expansion joints & contraction joints?

Consider that the concrete structure is not subject to the problem of differential settlement. For contraction joints, it may be possible to design a concrete structure without any contraction joints. ... Therefore, the structure has to be designed to take up these thermal stresses if expansion joints are not provided.

Ajedi32

Guest

What is a concrete bridge?

Concrete bridges are generally either arch or beam in structural type.

The beam is by far the most common structural element used in bridges.

An arch carries the load of the bridge, mainly by axial compressive thrust in the member developed by the resistance against spread of the arch at the abutments..

Aaron Digulla

Guest

Can you pour cement in hot weather?

When pouring concrete in hot weather, space control joints at smaller intervals than cold weather concrete joints. Use sunshades or windbreaks to reduce possible harsh conditions. ... Use ice as part of the concrete water mix to cool the concrete. Reduce the mixing time once water has been added to the mix.

floatingpurr

Guest

Can you pour concrete a little at a time?

The thing with larger slabs is that they usually require the entire amount of required concrete at one time. If you don't pour the whole thing at once, you get cold joints. Cold joints happen when concrete poured into a slab is allowed to partially or completely dry before more concrete is added.

Dominic Rodger

Guest

Can you pour concrete over plumbing?

As long as the concrete pours correctly and the line supports minimal weight, it should be fine. The pipe should also be sealed appropriately at any joints to ensure that water from the wet concrete does not seep into any joints damaging the seal of the line.

Shaun Luttin

Guest

Why is my concrete 2 different colors?

Calcium chloride in concrete is a primary cause of concrete discoloration. ... The resulting low water-cement ratio affects the hydration of the cement ferrites, which contributes to a darker color. Concrete surfaces that are troweled too early will increase the water-cement ratio at the surface and lighten the color.

AlbertK

Guest

How much space should be between cement board and tub?

1/4"The backer board should overlap the tub flange so the tile has a stable backing to attach to. This requires shimming the backer board out from the studs so the wall is plumb. There should be a 1/4" gap between the tub ledge and the backer board.

M. Bilal Asif

Guest

How do I keep my concrete slab from cracking?

4 WAYS TO PREVENT CRACKED CONCRETEStart with a sound subgrade. Make sure the subgrade is compacted. ... Modify the concrete mix. Use a low water-to-cement ratio. ... Install joints. Be active in deciding where control joints will be placed. ... Properly cure the concrete. Properly curing concrete slabs: Why and how to cure.

nemo

Guest

Are concrete homes energy efficient?

Energy efficiency. Thanks to high energy prices, this benefit is "a close second" in attracting buyers to concrete homes, Pfanmiller says. The thermal mass of the walls and the tight seals at joints enable concrete homes to excel at keeping conditioned air in and extreme temperatures out.

Hao Wu

Guest

How can Cracks in concrete be avoided?

4 WAYS TO PREVENT CRACKED CONCRETEStart with a sound subgrade. Make sure the subgrade is compacted. ... Modify the concrete mix. Use a low water-to-cement ratio. ... Install joints. Be active in deciding where control joints will be placed. ... Properly cure the concrete. Properly curing concrete slabs: Why and how to cure.

tzot

Guest

How do you fill gaps between concrete and wood?

How to Water Proof Between Wood & CementLoad a tube of caulk into a caulking gun. ... Cut the end of the caulk tube off with a utility knife to accommodate the size of the gap between the wood and the cement. ... Fill the gap between the wood and the cement with backer rod if needed.More items...•

Pointy

Guest

Is there a special cement for fireplaces?

QUIKRETE® Fireplace Mortar (No. 8620-21) is a silicate based refractory cement caulk for tuck-pointing damaged fireplace mortar joints and repairing cracked or chipped firebricks in fireplaces and wood-burning stoves.

Pascal Cuoq

Guest

What is the importance of cement industry?

Because it is a major component of both of these building materials, cement is an extremely important construction material. It is used in the production of the many structures that make up the modern world including buildings, bridges, harbours, runways and roads.

Guruparan Giritharan

Guest

What is the importance of these expansion joints in concrete or steel roads?

An expansion joint is designed to absorb safely the expansion and contraction of several construction materials, absorb vibrations, and permit soil movements due to earthquakes or ground settlement. The expansion joints are normally located between sections of bridges, paving slabs, railway tracks, and piping systems.

Tlerio

Guest

What can I use for concrete expansion joints?

A pliable material is used (asphalt coated, cork, plastic) to construct these types of joints. The material should extend the depth of the slab and extend the full width of the slab. Ideally, for expansion joints on the exterior of a structure, sealing these joint is preferable.

cletus

Guest

Why is my concrete floor always wet?

There are a couple of reasons why your garage floor may be getting wet. The most common is condensation — AKA sweating garage floor. ... If the air cools at or below the dew point, it will begin to condense on the surface of the concrete, thus causing the wet and sometimes misty looking garage floor.

Anand S Kumar

Guest

Why is Roman cement so strong?

Roman concrete is durable due to its incorporation of volcanic ash, which prevents cracks from spreading. Some Roman concretes were able to be set underwater, which was useful for bridges and other waterside construction.

burningalc

Guest

Why is Roman concrete so strong?

Roman concrete is durable due to its incorporation of volcanic ash, which prevents cracks from spreading. Some Roman concretes were able to be set underwater, which was useful for bridges and other waterside construction.

Roel Spilker

Guest

Why reinforced concrete is used?

What is reinforced concrete used for? Reinforced concrete is used for construction on a large scale, such as bridges, dams, piers, tall buildings and stadiums. It is most commonly used in domestic construction for the footings and foundations of smaller everyday dwellings.

Yawar

Guest

Why tensile strength of concrete is low?

Originally Answered: Why Does Concrete has low Tensile strength ? In concrete small cracks are there and when tensile force acts these cracks are widened. Tensile force can be transferred only through the uncracked concrete. That's why concrete is weak in tension.

Philipp Claßen

Guest

How do you fill a large gap in a concrete driveway?

The best way to repair your expansion gap is to use purpose-designed foam backer rods and self-leveling caulk. Both materials are available in most home improvement stores. Cut your foam backer rods to the proper length for your expansion gap and press them into the gap.

Tushar Sharma

Guest

How do you fill gap between cement board and drywall?

Fill the gap between the boards with mortar using the 6-inch taping knife. Force it into the gap and apply a thin layer on both sides of the joint for a total width of 3 to 4 inches. Place fiberglass mesh tape over the entire length of the joint and smooth it with the knife.

JB-007

Guest

How do you fill seam between drywall and cement board?

Fill the gap between the boards with mortar using the 6-inch taping knife. Force it into the gap and apply a thin layer on both sides of the joint for a total width of 3 to 4 inches. Place fiberglass mesh tape over the entire length of the joint and smooth it with the knife.

Hamza usman ghani

Guest

How do you fix a gap between concrete and asphalt?

Start at one end of the gap, and install the sealant to fill the gap so the sealant is even with the surface of the asphalt. Allow the sealant to cure overnight before walking or driving on the gap. For gaps wider than 1/4 inch, you can use foam pipe insulation to make the seal.

Pablo Barrera

Guest

How do you install cement board on plywood?

Leave a 1/4″ gap between the backer board and walls and 1/16” gap between the sheets of backer board.

Mix up and apply a modified thinset to a large enough area of the plywood subfloor to cover each piece of backer board using a 1/4″ x 1/4″ notched trowel..

Thomas Pornin

Guest

How do you seal between concrete and asphalt?

Start at one end of the gap, and install the sealant to fill the gap so the sealant is even with the surface of the asphalt.

Allow the sealant to cure overnight before walking or driving on the gap.

For gaps wider than 1/4 inch, you can use foam pipe insulation to make the seal..

Siguza

Guest

Why are cement prices so high?

As more areas become industrialized—and as there grows a greater need for durable building materials to withstand severe weather and long-term wear—the demand for concrete has significantly increased. This alone has affected the price of concrete over the years.

Joseph Mansfield

Guest

Why does concrete crack after pouring?

There are a number of reasons why concrete cracks. The most common is because concrete shrinks as the excess water evaporates and it hardens. Unfortunately, too often contractors add too much water to the mix, which makes it easier to apply but also more vulnerable to cracking.

leftjoin

Guest

Why does sand and cement render crack?

Cracking caused by failure to replicate underlying movement joints. It stands to reason that if the underlying substrate has inbuilt movement joints then these need to be replicated directly above in the render coat. If the render coat cannot accommodate and mirror the underlying substrate movement then it will crack.

Keith

Guest

How thick is the mortar between concrete blocks?

Lay out the block, making sure to leave a 3/8 inch gap between the blocks to allow for the vertical mortar joints (i.e., a typical 8x8x16 block is actually 15-5/8 inches long and 7-5/8 inches high to accommodate the mortar joint).

Ruchira Gayan Ranaweera

Guest

Why is there a large demand for cement in Pakistan?

In Pakistan, infrastructure projects and the housing sector are the key drivers for consumption of cement. Going forward, consumption of cement from these two sectors is projected to increase.