A Study On Structural Formworks In High Rise Building Construction
In the most recent couple of years extensive requirement for tall structures has been building up. Specific accentuation has been given to decrease the time duration in finishing of these undertakings. Therefore, formworks have been acquainted in order to diminish time and also work cost of such industries.
Structural Form works utilized as a part of the Construction has gigantic favorable circumstances due to the speed of finishing of the building. But as this Auto Climbing System is likewise utilized at great heights these variables could prompt significant dangers. These are for the most part utilized as a part of constructing main wall/ divider which fills in as the foundation of the whole structure of the building.
Few of such hazards can consist of workers working on platforms posing a threat of tumbling from tallness, damage from equipment tumbling from stature to the individual working underneath the platform. More preference should be given amid the Jumping/Lifting of such platforms. At the point when the platforms are hoisted from a lower level to a larger , more amount of dangers are presented. The objective for this study is to understand different dangers and risks associated with the utilization of such basic form works in the construction business and give legitimate and suitable methods for control measures.
India is a fast growing country with its cities growing even faster and expanding to newer limits. Such exceptional growth stories have pulled in people from different parts of India to settle and work in its cities. This has led to growing demand of living space required for city families as well as office spaces for companies and other services .For such development plan, limited city area is one of the key reasons for concern. Specifically the expansion of city spaces through horizontal construction is possible only up to a certain extent and will further lead to shrinking of available area for other projects. Therefore high rise buildings in cities are the need of the hour and an efficient way of land management and utilization.
In many developed cities around the world their skylines are as famous as the cities themselves. High rise buildings are not just architectural and infrastructural marvels but become a part of city identity and icon. Tall buildings are a marker of city life as well as a standard of better quality of life. Its main benefit is the ability to accommodate a large amount of people with each vertical ascent and thereby saving up a lot of land. Other benefits include lesser exposure to air and noise pollution but better access to natural light and ventilation while offering a high vantage point view of the city itself.
Tall structures offer a refuge from floods but it needs design fortification to protect it from other natural calamities like high intensity wind force and lightning. Therefore safety rules and regulation need to be strictly laid out and followed during construction of high rise buildings. Structural stability and security are key aspects of such building safety as they have to be earthquake and fire resistant .In case of high rise buildings it is their height that determines whether safety compliance needs to be fulfilled or not and as such builders have to overlook and furnish fire and earthquake safety plans and exit routes, rescue spaces, electricity supply, service ducts, elevators among others.
The construction of high rise buildings requires advanced technology and machinery to aid in the process. One of such new advancement is the Auto Climbing System which is a hydraulically operated self-climbing formwork system. It is useful because it significantly reduces the completion time of construction projects and safer compared to the traditional method of crane lifted formwork often referred to as “jump” forms.There is a need to evaluate the safety of the platforms installed for a secure working environment as there have been reports of industry accidents occuring when the platform is lifted from one level to another.
This technique requires more crane time and is too sluggish, dangerous and inefficient for tall structures where the concrete walls dividers are consistently on the analytical way. Despite the fact that Auto or Self climbing framework is a tremendous advancement in diminishing the time required for completing the project, we can’t disregard the small deficiency in these frameworks.
The importance of this thesis is to give a secure workplace to the work persons and all the staff performing work on or underneath the platform. Huge importance should be given for the establishment of these platforms. It has been generally seen that ,while lifting or jumping of the platform has been carried out , very less investigation has been done as far as the well being of this specific action is concerned. However, a number of accidents have been accounted for while lifting the platform starting with one level then onto the next.
Automated Climbing System can be generally used for the outer part of the main concrete wall, because of the exterior look of building that is concrete or a tower that supports the cables. One of the main benefits of Automated Climbing system format includes the lack of over wall that acts like an obstruction which in return allows the steel to be put in a proper manner on the ground ; can be carried to places via mats. ACS arrangement is particularly used for the insides of the main wall as well as used for lifting both inside ; outside part of formwork for building.
The first step starts with removing the casing, by using carriages, of the previous casting and then by screwing the climbing shoes to the anchor. These climbing shoes are bolted on every platform which is locked automatically. After that the mechanism is swapped which now climbs the unit than the rail, which is generally done at 50cm/min. when the unit reaches the climbing shoe, before disabling the hydraulics, it is locked using bars and then with the help of carriage, rebar is fixed by positioning the framework which is ready to be finned with concrete, finally completing the construction cycle.
While selecting a proper ACS format for a concerned project, factors that need to be decided are: building form, sequence in which construction will take place, the number and time of cycles need to me mentioned properly, work that needs to be reinforced, and specification needed during placement of boom while climbing. Formworks are divided into wide number of types based on different sizes, location where it will be used, equipments needed for construction, operation nature.
Major hazards identified in structural formworks
• Extreme weather conditions like heavy rain and strong winds can cause problems in hanging type platform. So proper assessment of weather conditions is of utmost importance.
• Unauthorized and untrained personnel should not be allowed to operate the platform as improper handling can cause major hazards.
• Fall of material from the platform on the ground below can be hazardous to person standing down.
• Ladders and scaffolds erected on temporary basis should be removed otherwise they can fall while lifting is performed.
• Strength of concrete should be high enough before fixing the platform.
• Length of cord must be long enough for performing lifting of platform otherwise they could get stretched and break causing spillage of hydraulic oil.
• Incompetent and untrained members could cause miscommunication while jumping on platform.
• Sufficient clearance must be provided between wall and platform so that it doesn’t scrape against the wall causing uneven lift.
• If protectors are not provided on platform it could cause slipping of profiles and lead to falling of platform.
• Proper access of the platform must be maintained to protect worker from getting stuck.
Safety norms and procedures to be followed during the operation of the climbing system.
a) On site safety for personnel
Climbing rescue walls at the edge of the slab and platform with protectors provide effective safety against falling and also provide protection against extreme weather conditions in case of work at height.
b) Safety from extreme weather conditions like high wind load
Climbing operations are of two types’ crane-dependent climbing procedure and self-climbing procedure. 72km/h is the max wind speed for self climbing procedures. According to German standards such structures are designed to withstand high wind loads. For high wind speeds of over 200km/h statistical proof can be provided.
c) Manufacturer’s service for providing safety to the personnel
Competent assembly personnel, engineers and supervisors should be available at all time for providing help beyond initial phase. Regular assembly and training must be conducted.
d) Improvement in quality for safety
EN ISO 9001 Quality System is followed for conducting internal procedures of the company. It provides the basis for best quality of the PERI equipment as well as high quality of development standards. Official approval is provided to PERI climbing anchors and quality of its components is maintained.
Control measures and recommendations:
It is absolutely imperative that the person operating the lifting of the auto climbing Systems of all hazards and risks associated with the working and the functioning of the auto climbing system. Hence we make it mandatory that the person operating has beengivenproper training an all thesafety aspects have been properly explain to him. Only a certifiedoperator from the manufacture should operate the lifting or jumping of the Auto climbing System.
Ensure that we observe all the weather conditions while lifting and operating the Auto climbing System. Extreme weather condition such as high wind speed and torrential rain, it is advisablew should not operate it in harsh climate conditions.
The next major hazard to look at is if any looseitem is present on the platform being lifted. During lifting, the material could roll onto the ground which could cause serious injuries to the person below. So, all loose materials should be removed from the platform.
Our main objective is to highlight the various circumstances ; constraints while managing the utilization of the formwork under various conventional conditions. As most of the major undertakings have to be completed under stipulated time period, so, there is no easy or effortless quick fix while using formwork for typical buildings.
We should not avoid the hazards associated with the utilization of formwork at work site. In order to just increase the rate of work to decrease the completion period of construction, it will be wrong to simply not notice the safety in construction because it may endanger the lives of each and every people associated with the work.
Therefore, it is very important to focus on the various safety features that have been highlighted in this study. The most important question that we all need to ask ourselves is that – “should we follow all the safety rules to have a risk free work place in order to complete the project in right time or should we just try to complete the given work by hook or by crook neglecting the rules thereby endangering all our lives as well as others?”