Cement, sand, lightweight aggregate, and various pozzolans such as fly ash, silica fume, shale, metakaolin, calcined clay, and superplasticizer are carefully mixed to generate high-performance lightweight concrete. The use of high-performance lightweight concrete in a variety of applications is highlighted. Precast constructions, such as bridges, parking garages, and long-span roof framing, are among the most common uses of high-performance lightweight concrete. Because the self weight of high performance light weight concrete is less than that of conventional concrete, larger bridge spans can be built without the transportation and erection issues that can arise when conventional concrete is used to build the same prestressed concrete member. Wabash Bridge was built with precast high performance lightweight concrete, as seen The tee girder bridge with post tensioning.
Construction of Precast Structure
The length of the post tensioned tee girder bridge is 53.4 metres, the depth is 2.3 metres, and each girder weighs roughly 96 tonnes. Not only did the structure’s weight decrease by 17 percent, but the total cost also decreased by 18 percent. As a result, it is apparent that this type of concrete enhances building efficiency while also lowering construction costs. Finally, for long span roof framing with about 37 m span length, high performance lightweight concrete was utilised. Precast Structure Construction Wabash River Bridge. Building Construction High-performance lightweight concrete has been used to build a variety of constructions. For both structural and aesthetic reasons, high-performance lightweight concrete was used. It was created to address issues that may arise when traditional concrete is employed.
Finally, high-performance lightweight concrete was used to build the Bank of America’s floor slabs to reduce slab dead load and obtain a three-hour fire resistance rating. Bank of America’s headquarters: The Bank of America Building. Bridge Structures Construction and Rehabilitation Various elements of bridge structure, such as decks, beams, girders, and piers, have been built with high-performance lightweight concrete. It delivers excellent concrete compressive strength with a high air content, resulting in a significant reduction in maintenance effort. This is the primary reason why bridge designers choose this type of concrete. In the construction of new bridge structures and the restoration of existing bridge structures, high-performance lightweight concrete is used.
Construction of Buildings
It has several advantages, including the ability to widen bridge decks without changing other structural elements such as piers, increased ultimate load carrying capacity of the bridge, reduced seismic inertia forces, increased concrete cover with the same weight used when conventional concrete is used, longer spans safe pier cost, and improved deck geometry. Finally, depicts a stretch of the Whitehurst motorway in the United States in greater detail. This motorway was renovated with high-performance lightweight concrete, which resulted in a reduction in dead load and an increase in total load bearing capacity. Whitehurst Freeway sections in the United States: Sections of the Whitehurst Freeway in the United States, A: Existing section of the bridge, B: Rehabilitated section of the bridge, with a total weight reduction of 205 kg/m2.
High-performance lightweight concrete is an excellent construction material for marine projects. This is due to the fact that offshore platforms are usually built in shipyards, floated and towed to the building site, and then erected at a predetermined spot.If the weights of marine structural elements were reduced, this construction procedure may be enhanced. The use of high-performance lightweight concrete can help achieve this reduction. As demonstrated by the Tarsuit caisson maintained island in British Columbia, high performance lightweight concrete may be employed to meet floating and draught criteria. Furthermore, it is used to improve the buoyancy of maritime platforms.
Rehabilitation of Bridge Structures
Excellent Performance Lightweight Concrete (HPLC) is a type of concrete that combines high strength, workability, low permeability, and durability with a low density. HPLC is a preferred material for many bridge designs due to its unique features. To save on transportation and construction costs, researchers advocated using HPLC in prestressed concrete bridge girders and panels. HPLC was also used on the decks of the Virginia Dare Bridge in Manteo, North Carolina, which was built in a corrosive coastal environment. The use of HPLC in a floating concrete barge gate, as well as its mix design and building procedures, is given in this study in order to achieve the desired performance and 100-year service life.
By providing reduced dead load, reduced seismic loading, longer spans, better fire ratings, thinner sections, decreased story height, smaller structural members, less reinforcing steel, and lower foundation costs, structural lightweight concrete provides design flexibility and significant cost savings. Trucking and placement expenses have been decreased thanks to structural lightweight concrete precast parts. The ceramic nature of the aggregate, as well as its outstanding bind to and elastic compatibility with the cementitious matrix, contribute to the excellent durability of structural lightweight concrete built using expanded shale, clay, or slate structural lightweight aggregate. The cellular structure of structural lightweight aggregate allows for internal curing by water entrainment, which is very helpful for high-performance concrete (HPC). Internal curing enhances the contact zone between the aggregate and the paste, reducing micro cracking.
Construction of Marine Structures
ESCS lightweight aggregate concrete has better thermal properties, higher fire ratings, reduced autogenous shrinkage, improved contact zone between aggregate and cement matrix, less micro-cracking as a result of better elastic compatibility, and better shock and sound absorption than ordinary concrete. High-performance lightweight aggregate concrete also has less cracking and improved skid resistance, and is easily placed by pumping.Uses of Structural Analysis Steel-framed buildings with lightweight concrete floors (lightweight concrete on fire-rated steel deck assemblies)Buildings with concrete frames and parking structures (all types, including post-tensioned floor systems) girders, bridge decks, and piers Concrete with a specific density (concrete between 120 pcf and 135 pcf) Beams, double-tees, tilt-up walls, raised access floor panel planks, hog slats, utility vaults, pipes, ornamentals, and other lightweight precast & prestressed concrete parts.
Lightweight concrete has a two-thousand-year history, and its technical progress is still ongoing. This assessment begins with a look back at the wide range of applications that lightweight concrete has served over the last century. Despite the fact that lightweight concrete is well-known and has demonstrated its technical promise in a wide range of applications over the years, there are still concerns and uncertainties in practise. As a result, the qualities of lightweight aggregates and the various types of lightweight concrete are thoroughly explored, with a special emphasis on current standards. The analysis is based on 25 years of practical and theoretical knowledge in the sector. One of the most difficult aspects of lightweight concrete design is adaptability.
High Performance Lightweight Concrete
Concrete lightweights are not a recent development in concrete technology. They have been around since antiquity and are the forerunners of today’s concrete. During the early Roman Empire, the first European references to lightweight concrete were created two thousand years ago. One of the most well-known examples is the Pantheon in Rome, Italy, which was built around 128 A.D. Over hundreds of years, it has astounded engineers from numerous fields by demonstrating the systematic utilisation of various natural lightweight aggregates in opus caementitium. Due to the scarcity and irregularity of natural volcanic materials after the Roman Empire fell apart, the use of lightweight concrete was restricted. The creation and production of lightweight aggregate produced in an industrial setting in the United States.
The high-performance concrete has been used in the construction of bridges, hydropower structures.
compressive strength Lightweight concrete has a substantially higher strength-to-mass ratio than regular concrete.
Foam concrete, also known as Lightweight Cellular Concrete (LCC), Low Density Cellular Concrete (LDCC).
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