Asphalt paver

History

Asphalt paver handling system that has developed original material, Barber Green was developed by the company.Machine developed. Were separated and the desired process and modern paver was on his way to set it up as not as effective. Was invented in 1933 the float to smooth and uniform material density and thickness of the bar when combined with tamper. Harry Barber patents a "machine for laying roads process" on 10 April 1936 and then filed for has been included in the most Pavers Barber Green Company by 6 December 1938. The main features of paver received a patent US Patent 2,138,828, improvements have been made to control the machine, though.

Operations

Asphalt paver hopper of a dump truck or a material transfer unit is included. Asphalt from the hopper to the auger conveyor carries. in front of the auger to smooth material gives a reservoir. Takes stock of road surfacing materials and more it spreads and initial compaction width offers
behind the paver screed should provide a smooth uniform surface. To provide a smooth surface is used a free floating screed. This last effect reduces the base topology which is towed at the end of a long arm. To smooth attack, angle and vibration of weight to smooth, tone and content of the towing force: to pave a number of factors including elevation is controlled by.
The information gathered usually a grade sensor which controls the angle of attack to pave the pavers using automatic control to smooth the road for the development of the final grade changes, according to. Additional control over the slope of the floor, are used to correct a crown or superelevation.
A constant reservoir of material in front of the screed paver should proceed at a constant speed and to achieve a smoother surface. More asphalt paving will cause an increase in physical stores or asphalt paver speed increases because a thicker mat and an uneven surface being placed last. Alternatively drop in speed or a reduction in material to be thin, smooth and mat will cause a fall.
And the need for a steady supply of materials in combination with paver to use a material transfer unit is one of the reasons. A material transfer unit level to provide a happy ending, without contact paver allows for continuous material feed. Paver's hopper to fill a dump truck is used, the speed change or make contact with the paver and screed height can cause it to suffer.

Concrete paving

Often on major highways are paved with concrete and it is using a slipform paver. Trucks piled up along the front of the machine and then throw in loads of readymix concrete slipform paver concrete spreads out to a smooth and level off using.

Road roller

 Road Roller used in construction work

 Road roller are used in construction work road and buildings. mostly used in road for compaction
in road construction first of all level the road where we laying the road after leveling doing the compaction on the road land in dry condition . after this some percentage of water are shrinkage on the road place then again compaction that are called wet compaction . after compleating this step laying the aggregate according to the specification some voids are empty and hollow for filling this hols using the sand in thickness of 1.5 inches . then again compaction on this place in dry condition and same as it after this wet condition rolling on the road surface now this road are called WBM (water bound macadem road ) after this step road open for traffic till to more compaction due to the weight of  vehical . in different types of roller are used in these work but mostly used the  foot ship roller because its weight of very high a good work depended on the good machine basically we used this for compaction .

Level road rollers being implemented (static) or compress (Hull) to use the mechanical advantage of the weight of the vehicle. A road project initial compaction of the substrate on the pad having a surface area less than a padfoot drum roller compaction density is achieved, is using. On major highways such as a caterpillar 815/825 series padfoot drum machine and a blade, with a four-wheel compactor, bulk material to spread its high weight, speed and a powerful force used to advance will be. A single regional roads can be used padfoot drum machine. The machine is generally smooth land until a smooth drum compactor that compacts down the high spots, and it is usually to get a level surface in combination with a motor grader is. Sometimes it will be used to stage a pneumatic tire roller. The two rows of rollers that overlap pneumatic tires (front and rear) feature, the flexibility of the cell and the wheels and tires with a vertical movement, uneven ground that enables us to work effectively provides a roller kneading action is. Once the base is flat soil compactor drum pad on the surface of the road is no longer used. The next course (road base) for maximum compaction with the right amount of moisture required to achieve a smooth flat surface of a drum, roller or smooth mill grader in combination with a pneumatic tire roller, and a water Using the truck will be strengthened. After being compacted road base, a smooth drum compactor on the road surface is no longer used (a special drum machine on flat tires are wide basis, however, is an exception). Asphalt concrete (asphalt or blacktop aka England in North America, or macadam) laid the final wearing course using a paver and a tandem smooth drum roller, a three-point or roller compacted using a pneumatic tire roller is . Three points on the asphalt rollers were once very common and is still used, but Mill Hill rollers kneading action of pneumatic tire roller surface to seal off the last roller with the usual choice now, do.
Also used in the compaction rollers. Such padfoot compactors general or "sheep's foot" drums, and do not get a smooth surface. Due to the small area of ​​the pad contacting the ground, in compression.

The effectiveness of a roller depends to a large extent on the weight, since the mid-19th century, self-propelled vehicles replaced horse-drawn rollers. The first such vehicles were steam rollers. A cylinder steam rollers usually used for the base and a vibrating roller compaction on similar lists in more bounce and vibration from the crankshaft through promoting a lower gear with high engine revs run was.was. High-geared models often hot asphalt laying machines and chipping which followed behind in the chip Chasers "was cited as the basis of smaller engines to slow as steam rollers were often gears by Young were dedicated to the task. Some companies in the US road used steamrollers through the 1950s, and in the UK, some in commercial service until the early 1970s.
20th century technology of the internal combustion engine, kerosene-, gasoline- (petrol) and diesel-powered rollers gradually improved during replaced their steam-powered counterparts. First, it changes the internal combustion steam powered road rollers rollers were very similar. The wheels, usually large, exposed spur gears transmit power from the engine, similar to the method used. Age engines, especially kerosene-powered ones were usually difficult to manage as some customers did not like them in their childhood.

Road cutting machine

Road cutting Machine

Pavement milling (Cold Planing, milling asphalt, or profiling) such a road, bridge, or a paved parking lot area is the process of removing at least part of the surface. Milling, surface and a depth to the surface for removal only removes sufficient thickness anywhere. Instead of milling a paved area is only for repaving the current level over a number of different reasons.

Recycling of road surface milling a road surface is one of the main reasons. Milling extensive floor to be used in the overall removed and the ground floor where recycling Today, it is used for.  for the milling of asphalt products which can be recycled asphalt pavement (RAP), is reclaimed aggregate and asphalt surfaces New cement (binder) or a recycling agent mixed with hot asphalt Mix Asphalt (pavement).  This resurfacing reduces impact on the environment is.

Milling a better driving experience and / or to extend the life of the road, away from the surface tension can be. Milling can eliminate some of the problems include:

Raveling: binder on the road and becoming loose from
Bleeding: the binder to the road surface (asphalt)
Rutting: low spots in the floor of the establishment as well as the direction of travel of the wheel
The shoving: a washboard effect transverse to the direction of travel
Ride quality: such as flowers, bumps's, sags, or recession, uneven road surfaces
Damage accidents and / or fire resulting in
It also controls all or part of the road can be used to change the height. The heights and other road structures such as the approval can be done to control: Stop, manhole and catch basin heights, shoulder and fence heights, and passed overhead shows  It also shields or to Camber can be changed or road, which can help with drainage for grade adjustment.


Special milling is often used along the highways in the Rumble strips can be used to form.  Instead, other methods such as rolling them, using milling, road surface hardening in the Rumble strips can be added at any time means.

DOWEL another example of the process of transition period in order to produce solid slap ROTO- milling head is to modify. Saw and jackhammer to cut the slots for the dowels is. DOWEL after placement, slot then usually with a non-shrinking concrete mix backfilled, and the floor is smooth recovery of diamonds are field. This special milling process is working during the traditional method is less time to create. 

Curber machine

Curber Machine 

In the construction work we are used the curber machine for concrete poring . in different members . mostly this machine are use for rcc barrier poring in the bridge constructions

sica folding for barrier very though  so there used the curber machine the slump of concrete we are uesde with curber is very siimple . ago using the concrete we are held some test on the concrete 

in these test mostly we uesd the slump con test we can find the slump of concrete with this test . its define by slump con 

in different shape of slump con used but stander size of slump 20cm diameter of the base of slump and 10 centimeter diameter of the top of slump con the heigt of slump con is 30 centimeter . the rod used for slump con for checking tyhe slump of concrete 

Biggest excavator in the world

Biggest excavator 

In the construction work mostly excavator are used for cutting and filling in the road construction and building construction in hill areas . different types of excavator are used in this work according to trhe nature of work.

When its construction was completed in 1978, the Bagger 288, the world's largest land the Space Shuttle and Apollo Saturn V vehicle as the launch vehicle (Marion Power Shovel Company of the excavation by the manufacturer built) take Used to go superseded NASA's Crawler-Transporter, for bucket wheel excavators are powered by an external power source 13,500 tons since. [1] NASA's Crawler-Transporter, still lives in the world is self-propelled land vehicle.

The Bagger 288 Hambach stripmine coal mining in Germany before the work was made for removing the overburden. A football field (Soccer) equal to 30 meters deep (98 feet) digging - it 240,000 tons of coal or [2] daily 240,000 cubic meters of overburden can dig. Coal produced in one day fills 2400 coal wagon. Digging high long 220 meters (721 feet) and approximately 96 meters (315 feet) across. The operation of Bagger 16.56 megawatts of externally supplied power is required. [3] This per minute (0.1 to 0.6 km / H) 2 to 10 m (6.6 to 32.8 feet) can travel. The main part of the chassis wide 46 meters (151 feet) and 3.8 meters wide each (12 feet), 4 Caterpillar track assembly sits on 3 rows. Bagger 288 large area of ​​the tracks that very little ground pressure (1.71 bar or 24.8 psi) means, it's a remarkable track excavator without leaving gravel, earth and even allowing them to travel on the grass . This is a minimum turning radius of approximately 100 meters, and the maximum gradient of 1:18 can climb.

Excavating head itself in diameter, 21.6 meters (70.9 feet) and 6.6 cubic meters of overburden (8.6 yd³) holding 18 buckets.

By February 2001, works entirely through Tagebau Hambach mine coal was exposed and there was not. Three weeks from the Autobahn 61, the river Erft, a railroad, and travel across several streets, Tagebau Garzweiler a 22 km (14 miles) made the trip. The move will cost about 15 million German marks and a team of seven workers. By the rivers of water to flow to large steel pipe with stones and gravel by providing a smoother surface than they were crossing. Special grass valuable area was seeded to smooth its passage. Bagger 288 excavator to remove in one piece and the piece of disassembling it was more economical to move the pieces.

arch bridge

Arch bridge

An arch bridge shaped as a curved arch is a bridge with abutments at each end. Arch bridge abutments on either side of the bridge partially prevented through a horizontally divided by moving the weight of the work. Other more economical structures are typically the oldest existing arch bridge in Greece about 1300 BC sentence today.Possibly Arkadiko bridge is used, although a bridge (a bridge), by a series of arches can be made. Stone corbel arch bridge still used by the local population.  The well-preserved Greek Eleutherna corbel arch bridge is a triangle.  4th century BC Rhodes Building rests on an early voussoir arch.

Arches truth already known by the Etruscans and the Greeks, though, were the Romans - as with vault and dome -. The bridge arches to fully realize the potential of engineered compiled by the first Roman bridges  A list of Colin O'Connor a stand still and even vehicles used to carry is 330 Roman stone bridge for traffic, 34 bridges and 54 Roman Roman wooden bridges groove features.  is an Italian by Vittorio Galliazzo a more complete survey found 931 Roman (including former Yugoslavia) as many as 26 different countries, mostly stone bridge.

A number that is less than a semicircle is a curved arch of a bridge (such as a bridge Alconétar) Roman segmental arch bridges arch bridge though, were usually semicircular.  The advantages of segmental arch bridge allowed the amount of water being swept away in the flood and the bridge itself can be more light will prevent the bridge, under which it to move. In general, the Roman bridges of the same primary arch shaped rock (part) as size and shape. Romans PONT DU GARD single spans and thus the tract of Segovia as long aqueducts multiple arch, built both. For example, featured an early time after the flood holes bridge piers, room for Pons Fabricius (62 BC), the world's oldest major bridges still standing one.



Roman engineers were the first industrial revolution and the only ones he met Opus caementicium, to build bridges with concrete. Usually the Alcantara bridge, as was done with brick or ashlar.

Segmental arch bridge built by the Romans introduced bridges. for more than a millennium bridge an unusually flat profile is unsurpassed Southwestern Turkey 330 meter long bridge-to-height ratio Limyra 5.3 with an average duration of 26 segmental arches features. Trajan's bridge over the Danube (up to 40 m high concrete piers) open-spandrel segmental arches made of wood featured. The longest existing Roman bridge Puente Romano in Merida is 790 meters long while, both overall and in terms of individual span length for a thousand years was to be the longest arch bridge. Featuring a pointed arch bridge in Cappadocia Karamagara late Roman bridge may represent the earliest surviving.


Devil's Bridge, TROPIC, France (1341)
In medieval Europe, the bridge builders of bridges, piers finely chop the barrel and low-rise span ratio improved by using Roman structures. Gothic pointed arches emphasize reducing the background, introduction, and spans eccentric Puente del Diablo (1282) were added as well.

In the 14th century saw the building of the bridge to reach new heights. Previously unheard of in the history of the arch masonry construction period of 40 meters lengthes ,, now Spain (Puente de San Martin), Italy (Castelvecchio Bridge) and France (Devil's Bridge and the Grand Pont) in places as diverse as the arch I came up with, as well as different types of semi-circular pointed arches and segmental. Trezzo sull'Adda Bridge, 15th century, destroyed, evening match length 72 m intervals, Featured 1796.


Ponte Vecchio, Florence, Italy (1345)
With aesthetical appeal of such acclaimed segmental arch bridge Ponte Vecchio in Florence (1345) combined sound engineering (1-to-height ratio of 5.3 over the period) as constructions. Renaissance Ponte Santa Trinita (1569) three beautiful arches of the oldest in the formation of elliptical arch bridge. More effectively on the background of a pile of wood was founded, in part, based on the smash hit obliquely to visit: Venice Rialto bridge structures such as low growing and (1-to-height ratio of 6.4 times), Nuremberg Fleischbrücke in which the mass of the abutments, the emphasis needs.


Richmond Bridge, the oldest operational Bridge in Australia (1825)
(With iron brackets buttressed) spandrel arches used in a 1: China, the oldest existing arch bridge span a 5.2-to-peak ratio for the 605 CE Zhaozhou Bridge is. Zhaozhou Bridge, 167 feet (51 meters) and 123 feet (37 m) length, with flood waters, allowing the passage of a large, open-spandrel stone segmental world's first fully-arch bridge.

In more modern times, stone and brick arches, Thomas Telford, Isambard Kingdom Brunel and civil engineers, including John Rennie, by continuing to build. A leading pioneer of little piers, modified calculation methods and span-to-height ratio of abnormal genes used for Rodolphe Perronet, said. Thus, cast iron, steel and concrete as different materials, have been increasingly used in the construction of arch bridges.

Design of lintel

Design of lintel

An horizantal member used for suporting the weight of masonary on the doors and windows . after using this the weight of masonary on the lintel transfeer the side members walls and column etc,Different times and in many cultures around the world architecture, is a lintel post and lintel construction element. Many different building materials have been used for lintels. A lintel or open space between two vertical supports that spans as a structural horizontal block is defined.

Classic Western construction methods, the lintel Merriam- defined by Webster's definition, a lintel and a load-bearing member is placed in the entranceway. In the Western classical architecture, called a lintel architrave, usually more than a portal or entranceway, or stacked stone pillars resting on stone columns that have a structural element. An example of Greece Cultural penalty period (c. 1600 BC - c. 1100 BC) Mycenae, Greece the Treasury of Atreus is in. It almost dimensions 8.3 × 5.2 × 1.2 m, with one of the largest in the world, weighing 120 tons.

A fireplace chimney support a lintel above the fireplace, and a stone lintel one way or road to the bridge that stretches over a distance which is a lintel.

Ornamental uses

During portals with no structural function as a decorative element lintel form of building,

architecture, traditions and cultures over the centuries has been employed in the genre.

An example of decoration of lintels Indian rock-cut architecture caves are Buddhist temples. Indian Buddhist temples in the prehistoric and subsequent structural load-bearing timber lintels over openings with wooden complexes. Excavated rock-cut cave temples were more durable, and non-load-bearing carved stone lintels classical Buddhist elements permitted uses creative decoration. Highly skilled artisans monolithic cave temples of stone and wood grain to dig a wooden structure resembling aspects, were able to simulate the look of wood. Freestanding building in India with examples, between the 11th and 14th century Hoysala architecture in the tradition of South India South Deccan Plateau region very elaborately carved stone lintels production of non-structural. Art and architecture of Hoysala Empire Kannadigan South Indian culture was an important phase in the development. This mainly Hindu temples, pavilion, lintels, and as such Chennakesava other architectural elements in the temple, is remembered today.

Maya civilization of the modern art in America and was known for monumental architecture. Lintel stone lintels ornamental elements within the structure of the stone carving skills in the Usumacinta River in present-day southern Mexico, Mayan city of Yaxchilan. The oldest carved lintels 723 AD was created. The archaeological site of Yaxchilan doorways of the main structures are lintels spanning fifty-eight with decorative pieces. To be excavated among the best in the Mayan carving from God's anointed king, a queen celebrates narrative scenes that feature the three temple door lintels.

Concrete slab design

CONCRETE SLAB DESIGNE

Concrete slabs common structural element of modern buildings. Steel horizontal slab 4 and 20 inches (100 and 500 mm) thick between the general, reinforced concrete, more often thinner slabs are also used to smooth the exterior, floor and roof construction is used for. Sometimes these thin slabs, 2 inch (5.1 cm) thick by 6 inches (15 cm) long, clay slab is especially important under the floor slab used c or crawl spaces.

Many household and industrial buildings or on the grounds directly supported subsoil, a thick concrete slab on the ground floor of a building used for construction. This "ground effect" or "suspended" so maybe slab. High-rise buildings and skyscrapers, the thin, pre-cast concrete slab floors and ceilings on each level to form steel frames are hung between.

Technical drawings, concrete slabs often "rccslab" or just "RC" are short reinforced.

There are two main thermal considerations. First is the question of insulating a floor slab. In older buildings, cast concrete slabs on the floor drain can heat a room. In modern construction, concrete slabs usually expanded polystyrene, such as putting on a layer of insulation, and the slab may contain underfloor heating pipes. However, it is still commonly used to heat or cool to room temperature in the outbuildings which are not, are an uninsulated slab is used. In these cases, a rocky slab casting directly on the substrate or substrate temperatures throughout the year will maintain the slab, and both can prevent freezing and overheating.

The second consideration walls and floors, or anywhere where concrete is used within the thermal envelope, which applies to the high thermal mass, is. This concrete building in a delay of warming, as it takes time to warm rooms, are intermittently heated and requires a quick response is a loss. But this season, with large daily temperature swings, is an advantage, where by day, by night, keeping the building cool and warm slab acts as a regulator.

For a suspended slab, power-to-weight ratio are a number of designs to improve. In all cases, the top surface is flat, and the underside modulated:

Corrugated, usually concrete is poured into a corrugated steel tray. It improves strength and bending under its own weight prevents the slab. In the short run amplitude corrugations, by.
A ribbed slab in a direction substantially additional strength.
A waffle slabs, both sides give extra power it down and look hollow.
is ribbed and Waffle slab foundations to reduce, compared to an equivalent flat slabs provide a light and stiff slabs. Laboratories and hospitals such as slab where vibration is a problem of a very good form.

Spanning the vertical direction is ribbed slab of ribs with deep narrow beam of wide band running between columns are made. A thick top slab system is complete.

ribbed slab is equal to waffle slabs are profound. a thin slab of waffle topping slab and column heads narrow ribs or bands have spread in both directions between the beams. Or band beam column heads are the same depth as the ribs.

Reinforcement Design

Along the long axis moment is so small that it can be ignored because it is a one-way slab just need a little help in the moment resistance. The long direction of the short side of a slab length ratio is greater than 2 the same way it can be considered as the slab.
Two-way slab reinforcement in both directions at the moment resistance is required. Long and short side length ratio of the two when both should be considered in the design.

pree tenssion of steel

Pree tenssion of steel

In various work we are use the steel with concrete that are called rcc*reinforcement cement concret if steel will be used before using the concrete then tahat are called pree tenssion steel  they are under stress-pre-tensioned concrete, steel rods or cables around-the tendons are inserted. This treatment, and the tension is released when the compression of static friction is transmitted to solid tendons as a solid bond. Imposed on the concrete stress is transmitted directly to the tendons.

Pre-tensioning the tendons are stretched between a strong, stable anchoring points is required. Thus, pre-tensioned concrete elements than the prefabricated and which may limit their size are transported to the construction site. Pre-tensioned beam elements, balconies, lintels, floor slabs or can be added to the pile. The emphasis on a modern bridge design is stressed ribbon bridge.

Bonded post-tensioned concrete after pouring concrete (in situ) during the curing process, a method for applying compression is a descriptive term. Concrete would otherwise be located in an area where tension concrete element to follow, a plastic, steel or aluminum is poured around the curved duct.

A set of tendons are pulled through the duct and the concrete is poured. Once the concrete has hardened, tendons of the concrete member is a reaction against the hydraulic jacks (push) are tensioned by.

Transfer pressure for concrete, tendons of the (see Hooke's law) according to design specifications, have grown, they are wedged in position and maintain tension after Jack is removed. Duct then grouted to protect the tendons from corrosion is in.

This method generally frame the issues for the Foundation's extensive land (sometimes called Adobe dirt) for construction of places where I create monolithic slabs are used to produce. Seasonal expansion and contraction of the soil supports all the stresses throughout the building without significant flexure-tensioned slabs, taken in.

Post-tensioning of concrete segmental bridge as well, falsework supported by the assembly of prefabricated parts and is treated by both used in the construction of various bridges.

unbonded post-tensioning the advantages of this system include:

traditional reinforcement requirements as tendons reduction in accidents can not destress.
the tendons allow a more efficient design approach "woven" could easily be.
Higher on the ultimate strength of the bond between the strand and concrete.
To build bridges in Europe this form of prestressing anchor / dead end.The maintain the integrity of popularity in the 1950s and 60s with no long-term problems surrounding increased significantly. However, a history of problems with long-term stability of such structures have been more skeptical have been encountered.

Poor workmanship or quality control during construction, sometimes consisting of prestressing tendons ducts are not fully protected from corrosion on steel, leaving voids in the grout, are not filled. Highway and water (from de icing salts) chloride are able to penetrate into the voids if the situation becomes serious.

Notable events are listed below:

West Glamorgan, post-tensioning particularly vulnerable to defects in post-tensioned segmental structure of Wales, in 1985 the Ynys-Y- Gwas bridge collapsed without warning system.
Melle bridge built during the 1950s in Belgium, the following members of the tendon corrosion failure of the post-tensioned tie demolished in 1992.
Tendon corrosion in England after the discovery of several bridges, highways agency in New internal grouted post-tensioned bridges issued on post-tensioned bridge stock and its current 5-year program of inspection work.
Charlotte Motor Speedway, USA, part of a footbridge gave way and he dropped to the ground in 2000, a number of people were injured. In this case, the de-icing salts sodium chloride corrosion addition, as a concrete mix that was used was exacerbated by calcium chloride.
Errors discovered in post-tensioning system since 2011, London, England, at the Hammersmith flyover was subject to an emergency closure.