বাংলাদেশে সেতু নির্মাণ কোম্পানি
সেতু, একটি কাঠামো যা সমর্থনগুলির মধ্যে অনুভূমিকভাবে বিস্তৃত, যার ক্ষমতা উল্লম্ব লোডগুলি বহন করা। প্রোটোটাইপিকাল ব্রিজটি খুবই সোজা-দুটি ব্যাকিং একটি রশ্মি ধরে রেখেছে-তবুও এই মৌলিক কাঠামোতেও ডিজাইনিং সমস্যাগুলি কাটিয়ে উঠতে হবে প্রতিটি সেতুতে অন্তর্নিহিত: সমর্থনগুলি নির্মাণকে ধরে রাখতে যথেষ্ট সক্ষম হওয়া উচিত, এবং সমর্থনগুলির মধ্যে পরিসীমা লোড বোঝাতে যথেষ্ট সক্ষম হওয়া উচিত। রেঞ্জ বা স্প্যানগুলি সাধারণত যতটা সম্ভব ছোট করা হয়; যেখানে গ্রহণযোগ্য স্থাপনা সীমাবদ্ধ থাকে সেখানে দীর্ঘ স্প্যানগুলিকে রক্ষা করা হয়-উদাহরণস্বরূপ, গভীর এবং গভীর জলের মোহনার উপরে।
সকল গুরুত্বপূর্ণ ও বড় সেতু জনগণের টাকায় নির্মিত হয়। এই পদ্ধতিতে, জনস্বার্থে সর্বোত্তমভাবে কাজ করে এমন সেতুর নকশার একটি ত্রিমুখী উদ্দেশ্য রয়েছে: যতটা কার্যকর, ততটা রক্ষণশীল এবং নিরাপদে যতটা সম্ভব সমৃদ্ধ হওয়া। উত্পাদনশীলতা একটি যৌক্তিক নিয়ম যা কার্যকর করার সময় হ্রাসকারী উপাদানের উপর মূল্য রাখে। অর্থনীতি হল একটি সামাজিক নিয়ম যা কার্যকারিতা ধরে রেখে নির্মাণ ও রক্ষণাবেক্ষণের খরচ কমিয়ে দেয়।
অবশেষে, কমনীয়তা হল একটি প্রতিনিধি বা চাক্ষুষ নীতি যা এক্সিকিউশন বা ইকোনমি ট্রেডিং ছাড়াই ডিজাইনারের স্বতন্ত্র বক্তব্যের উপর মূল্য রাখে। দক্ষতা এবং অর্থনীতি যা নিয়ে গঠিত তা নিয়ে সামান্য বিরোধ রয়েছে, তবুও একটি শ্রেণীর অর্থ ধারাবাহিকভাবে প্রশ্নবিদ্ধ হয়েছে।
Main Parts of a Bridge Construction
Let’s look at the main parts of a bridge in more detail and consider the components that make up the three core areas:
Piles: Piles are normally laid to give support to a bridge and make up the underlying foundation. The piles help the weight and stress applied by the bridge to be communicated equitably through the ground making it steady and solid.
The material and design of a pile rely upon a few factors, for example, soil type, ground fragility, and burden-bearing limit requirement. For bridges on rivers, scouring is additionally considered before the bridge is designed.
Caps: Caps give extra load moving ability to the piles. They are otherwise called pile caps as they are put directly on top of the heap establishment. Caps are frequently made of weighty cement to invigorate most extreme the upper piece of the bridge.
Bents: When piles and caps are set together they are called bents. Numerous bents structure the establishment for the base.
Abutments: Bridges have vertical supports at their moving toward grounds, working as maintenance walls for the ground. These are worked from supported cement and are equipped for withstanding significant levels of horizontal force.
Piers: When there are multiples spans in a bridge, then, at that point wharves are mounted toward the end of each to give sustenance from powers and vibrational impacts, going about as supporting focuses for the bridge.
Pier Caps: Pier caps are also called the head-stock. This capacity is space for braces to move loads on the course (that split the pile between every one of the wharves), from the superstructure parts on the top.
Girders: Girders join all the pile caps together by reaching out over them. Braces are additionally alluded to as pillars and offer help to the deck. This can be a single span, or even different spans joining every one of the bents, subject to the length of the bridge. Girders typically have a truss design to improve pressure and load resistibility. Subsequently, pressure is immediately passed towards the foundation. Girders are for the most part produced using metal or cement.
Bearings: Bearings provide allowance between these parts. Bearings are underlying individuals equipped for moving loads from the deck to the base. These dislodge stresses and load the docks through the braces to permit construction between parts of a bridge. The movement can be straight just as torsional. Heading gives recompense between these parts.
Trusses: Trusses are made by joining three-sided segments to isolate loads and bending moments through the bridge. A few kinds are simple trusses, suspension, and furthermore cantilever supports. The truss network gives a surface to transportation which can be worked as deck support, horse bracket, or through support. Each support contrasts in how the rush hour gridlock will continue forward the bridge.
Decks: Decks get the immediate traffic load. Some essential decks can be made of cement and furthermore from metal. These incorporate travel or strolling ways, seepage frameworks, checks, development segments, walkways, and approach pieces.
Barriers: Mainly as security and assurance include, spans have hindrances on the sides of their decks. These can be uncommonly planned installations, ropes, rails, fences, or substantial dividers for a better feel.
Arches: A bridge with arches has a ton of strength. Arches can help control the security and load-bearing capacity of the bridge. The amount of curves and materials used for construction is vital. A space interfacing the bridge columns and deck shaft are known as the spandrel. There can be open or shut spandrels relying upon the arch design.
Bridges play a crucial role in transportation. As such, multifaceted calculations and in-depth feasibility analysis are carried out before the design for a bridge is finalised. Aspects like the environment, load capacity, soil type and preservation, material, construction methodologies and techniques all need be taken into consideration when planning a bridge.
Materials Used for Bridge Construction
Some of the main materials found on construction of a bridge are steel, concrete, stone and asphalt. Other materials include iron, timber, aluminium, rubber and other joint materials. Below is a description of some typical uses for these materials in a bridge construction.
Concrete is usually used for some bridge superstructure individuals like decks, pre-focused on cement footers, checks, walkways, and railings (side traffic hindrance dividers). It is used broadly in new construction for the whole projection, including the footings, stem (fundamental front divider), wing dividers, cheek dividers, back dividers, end dividers (for traffic obstruction association), bar seats, and the wharf with comparable members. It can also be used for cast set up or precast substantial heaps to help the abutments and piers.
Steel is regularly used in the bridge superstructure for protecting expansion joints, bars, heading, and floor radiates, supports, building up bars in concrete, traffic obstructions and brackets. It is used in the foundation for the building up bars in concrete, reinforcing for extension joints, anchor bolts, and so on. It is also used for piles to support the abutments and piers.
Stone was regularly used for building projections and docks during the 1940s and prior. This is especially obvious where neighbourhood field-stone was promptly accessible.
Asphalt is the material that has been used widely for the wearing surfaces on folded metal decks, lumber decks, and substantial decks in bridge construction.
Iron was used commonly in pillars and trusses that were worked before 1900 for construction of a bridge. Steel supplanted iron since it has more rigidity than iron and is less weak. There are basically no uses for iron in the present bridge design.
Timber or wood is used for a few decks and traffic boundaries in Bangladesh. It is also used for the pillars on one extension and the projections and piles on another bridge.
Types of Bridges
Arch Bridges
There are various types of curve bridge yet they all share focal components for all intents and purpose. Each bridge has abutments, which are used to help the bended arch structure under the bridge. The most widely recognized sort of arch Bridge is a viaduct, a long bridge made of numerous arches.
The sidelong pressing factor made by the arch span is moved into the supporting projections. It is in this way fundamental that these pieces of the scaffold stay strong, flawless and very much established.
Truss bridges
The truss bridge has been around for in a real sense hundreds of years and is a load-bearing construction which fuses a support in a profoundly proficient yet basic plan. You will see a variety of several varieties of the basic support bridge yet they all fuse three-sided areas. The part of these three-sided components is significant in light of the fact that they viably assimilate pressure and pressure to make a focused on structure ready to oblige dynamic burdens. This combination of pressure and pressure guarantees the design of the bridge is kept up and the decking area remains positive even in generally strong winds.
Cantilever bridges
At the point when the primary cantilever bridge was designed it was viewed as a significant engineering breakthrough. The bridge works by using cantilevers which might be straightforward pillars or supports.
They are produced using pre-focused on concrete or underlying steel when used to oblige traffic. At the point when you consider that the even bars making up the cantilever arm are just upheld from one side it starts to sound somewhat risky.
Beam Bridges
A beam bridge is probably the simplest kind of bridge. An ideal example being an essential log bridge – something you may see while out on a nation walk.
The deck region generally comprises of wood board or stone slabs (regularly alluded to as a clapper bridge). These are supported either side by two beams running between projections/piers
Suspension Bridges
The construction of a stereotypical suspension bridge looks basic however the plan is very viable. The deck of the suspension bridge is the load-bearing component of the design. This is held set up by vertical suspenders which support the cables. The suspension cables extend out past each side of the bridge and are secured immovably into the ground.
Tied Arch Bridges
The tied arch bridge is an intriguing design which fuses a curve structure (generally metal) supported by vertical ties between the arch and the deck. The tips of the arch structure are associated by a bottom chord. This demonstrates also to the line of a bow. The descending pressing factor from the arch design to the deck of the bridge is converted into strain by the upward ties. Numerous individuals expect that the projections guarantee that the tied arch bridge and arch structure stay in space.
Cable-Stayed bridges
A cable stayed bridge is dependent upon towers/pylons which are the load-bearing element of the structure. Cables are bridged from the pylons to the deck below. This is the feature many people associate with cable stayed bridges. This type of structure tends to be used for distances greater than those achieved with a cantilever bridge design but less than a suspension bridge.
Different Methods of Bridge Construction
Described below are the different methods in the construction of bridges.
This method is an adaptable and flexible method for bridge construction where complex and uncommon mathematical states of dams can be built without any problem. In circumstances when it is difficult to transport prefabricated components either because of size or inaccessibility, this method is a decent choice. Bridge Construction Company will help you to construct a bridge applying this method.
This method is used for constructing bridges range 50 to 250m. The bridge constructed can either be cast-in-place or precast. Here, the portions are attached in an elective way at far edges of the cantilevers supported by piers. This is the most ideal decision for the construction of long-span length bridges, sporadic length, and cable-stayed bridges.
In this method, the bridge is constructed with the assistance of precast substantial components. The construction is acted in various methods. The precast components include:
A. Precast Beams
B. Precast Decks
C. Precast Segmental Decks
This method is related with the cantilever construction strategy however with much progression in the procedure, it is considered as generally monetary and fast in construction. For long bridges and viaducts with an individual span up to 60m, the strategy is feasible. Decks are started at one abutment and constructed persistently by putting sections to the opposite end of the bridge. Sections can be situated by either a transitory remaining pole framework through more generally using a get together support.
The Incremental Launching Method (ILM) method for bridge construction is used predominantly for the construction of constant substantial bridges or steel support spans. The method performs the procedure in increments. With this method of construction, the bridge deck is underlying areas by pushing the design outwards from a projection towards the pier. The ILM method can be used for bridge decks with a length more noteworthy than 250m.
In the cable-stayed method of construction, cables are used to convey the bridge deck from one or the two sides of the supporting tower. The cables convey and move every one of the loads to the foundations. Cable-stayed method of construction is used for constructing bridges that span more than 300m.
Arch shaped bridge construction is quite possibly the most conservative decisions when the bridge under consideration is needed to get over scenes that are distant. Many modern arch construction methods have made arch construction more efficient. The arch construction can be worked with concrete or pre-cast concrete. The cast-in-situ free cantilever methods and slip-framed areas are two primary construction procedures going under arch methods.
Factors Affecting Selection of Bridge Construction Methods
Before a bridge can be built an appropriate method of construction must be chosen. The decision is made by the design team. The principle factors considered by the design team when choosing a suitable method of construction are given below:
- The scale of the bridge
- The obstacles to be crossed
- The regularity of the span lengths
- The horizontal and vertical profiles of the bridge decks
- The nature of the soil strata
- The local weather
- The local cost of materials
- The local labor markets
- The accessibility of the site
- The time allowed for construction.
Our Bridge Construction Services
Over the years, At-Takasur Consultancy Firm has built some of the country’s most notable bridges. We pride ourselves on our ability to utilize in-house engineering to develop the tools, equipment, and methods for the timely and safe construction of bridge structures throughout the country. Let’s check out some bridges we constructed in various time periods.
Cable-stayed Bridges
From foundations to tower tops, and every part in between, At-Takasur Consultancy Firm has excelled at the construction of cable-stayed bridges since our earliest days. We are experienced with foundations; towers and piers; stay-cable fabrication, erection, and tensioning; suspension cable erection, superstructure erection, structural health monitoring system installation, and maintenance and repair. Maintaining global relationships with suppliers of fabricated structural steel is core to our business. We use leading technology for the engineering and erection of main cables, suspender cables, deck segments, load transfers, and compaction and wrapping of main cables.
Movable
We have constructed all types of movable bridges and other moving structures, including vertical lift, bascule, and swing spans. We self-perform mechanical equipment installation, calibration, and commissioning in addition to foundations, piers, and structural construction. Our experience covers truss float-in methods, bascule girder erection, counterweight jacking systems, counterweight suspension system installation, and replacement, and primary and secondary reducer procurement.
Arch Bridge
At-Takasur Consultancy Firm has constructed both true and tied arch bridges using aerial cable-ways, tieback, float-in, falsework, and jacking technologies. Over the course of our history, we’ve constructed more than 15 arch bridges, serving pedestrians, automobiles, and railroads.
Truss Bridge
We have experience with truss erection by balance cantilever, single pick, float-in, tie-back, launch, and slide-in – using water-based cranes, land-based cranes, traveling gantries, and jacks. We also construct and maintain truss bridge foundations, piers, abutments, and decks.
Why Choose “At-Takasur Consultancy Firm” as the Best Bridge Construction Company in Bangladesh
At-Takasur Consultancy Firm is the leading and largest family-owned bridge Construction Company in Bangladesh with unparalleled self-perform experience and resources to serve the transportation sector by constructing iconic bridges in Bangladesh. We are the preferred contractors for bridge construction. We are having vast experience in the field of bridge construction. We have completed several projects on the bridge in past and we are also running new bridge projects all over the country.
- Safety: Safety in all we do and build is fundamental to prosperity for our customers and our employee-owners.
- Experience: Established in 2019, At-Takasur Consultancy Firm is a leading bridge Construction Company in the country. Our expertise spans multiple markets, including transportation, industrial, building, concrete, and renewable s.
- Self-perform: There are many ways to control quality, and one of the best is to do the work yourself.
- Innovation: At At-Takasur Consultancy Firm, innovation isn’t just a word we write into proposals. It’s a value hardwired in the way we work.
- Social Responsibility: We build prosperity by sharing our own. Giving back and responsible stewardship are core parts of our culture.
Our Working Process
For Bridge construction, At-Takasur Consultancy Firm has more than 4 years of construction knowledge in river works, drainage, utilities, and the civil engineering sectors. Through our uplifting perspective on plans and our goal-oriented thoughts, we have built a reputation that we will continue to build on. We are committed to delivering to our clients a professional and no-fuss service. We are pleased with the information and experience we have acquired and we are fully focused on being a market leader in the many years to come.
When our clients choose us for constructing a bridge. We first arrange a meeting with them and hear about their plan about constructing the bridge. After hearing from them, we discus with them what we can do or cannot do with their planning.
After the meeting and planning about the bridge construction, we along with our clients go to the construction site for seeing the place where the bridge will be construct. Visiting a real time construction project allows to develop a greater understanding of the bridge construction. Based on the location and the condition of the waterways and soil of the areas, the bridge design will be edited and developed.
The initial phase in any bridge construction is appropriate planning and evaluating the necessities which is proposed to serve. Local soil condition both current and future ought to be contemplated, and a cost-effective analysis should be performed by private organisations to ensure they will actually receive good value for their investment in construction.
The execution phase turns the construction plan into action. Our expert engineering team carries out all the planned activities, constructs deliverables, and presents them to project stakeholders. Effective communication plays a huge role during execution of the bridge construction. We ensure that the budget stipulated in the planning stage that should be followed strictly.
Over time, waterway and environmental effects will damage bridge piles and other part of the bridge which require rehabilitation. Life expectation of bridge construction and maintenance projects varies from country to country, but we always tries to monitoring the projects after successfully delivered that to our clients.