International Journal of Civil Engineering and Technology (IJCIET) Volume 8, Issue 7, July 2017, pp. 358–372, Article ID: IJCIET_08_07_039 Available online at http://iaeme.com/Home/issue/IJCIET?Volume=8&Issue=7 ISSN Print: 0976-6308 and ISSN Online: 0976-6316 © IAEME Publication Scopus Indexed SAFETY MANAGEMENT DURING BUILDING DEMOLITION-A STUDY Prof. D. Muthu Assistant Professor, SASTRA University, Thanjavur, Tamil Nadu, India Dr. C. Venkatasubramanian Associate Professor, SASTRA University, Thanjavur, Tamil Nadu, India Aparna Balasubramania Sharma B.Tech, Civil Engineering, SASTRA University, Thanjavur, Tamil Nadu, India Snehalatha S B.Tech, Civil Engineering, SASTRA University, Thanjavur, Tamil Nadu, India M Kazalli M.Tech, Civil Engineering, SASTRA University, Thanjavur, Tamil Nadu, India ABSTRACT Construction industry deals with the construction and maintenance of the environment creating roads, dams, buildings and bridges. It consistently improves the life of the people by upgrading the facilities for them. It employs many people all over the world and plays a strong role in globalization. Accidents are often recorded every year during construction and demolition. In India, most of the structures are not demolished even after their life span. This is unsafe for all the occupants of the old building. Demolishing of the structure is done before the end of its service life on most of the other countries. Similarly demolition should also be carried out wherever required in India keeping safety as of prime importance. Thus Structures are to be demolished at the end of their design life for the safety of the people residing in them and around so that accidents cannot happen. For various renovation and rehabilitation projects, demolishing of structures is done. Unplanned collapse of structures, exposure to hazardous chemicals and explosives, vibrations due to demolition affecting the adjacent structures and noise pollution are some of the common risks involved in demolition. The steps involved before demolition are proper pre-planning, preparation of a stability report and taking up the necessary safety measures. This paper gives a brief description about the different types of mechanical and chemical methods used for demolition. The need to manage the demolition waste has led to environment friendly actions such as sustainable demolition and recycled construction. This paper provides insight about managing the debris produced due to http://iaeme.com/Home/journal/IJCIET 358 [email protected] Safety Management during Building Demolition-A Study natural disasters and prevention of its impact on health of humans and the environment. This paper mainly helps to choose the right method for demolition, its key objective being the safety of both the workers, occupants and the environment. Key words: Demolition, Safety, Debris, Vibration. Cite this Article: Muthu, Venkatasubramanian, Aparna Balasubramania Sharma, Snehalatha S and M Kazalli.Safety Management during Building Demolition-A Study.International Journal of Civil Engineering and Technology, 8(7), 2017, pp. 358–372. http://iaeme.com/Home/issue/IJCIET?Volume=8&Issue=7 1. INTRODUCTION This paper “Safety management during building demolition” is done with the sole aim of accomplishing safe building demolition. The demolition technique adopted depends upon factors such as site condition, type of structure, age of building, height of building and cost allotted for demolition. Most important factor for determining the method for demolition is the surrounding environment and the structural stability. To reduce on the demolition wastage in order to minimize the impact of the construction industry on the environment, the materials obtained from demolition can be used for recycling. By adopting the appropriate techniques for demolition depending upon the situation, accidents are reduced with less environment impacts. The objective is to provide safety during building demolition, to minimize the risk of injuries to people and properties, for the health and safety of the workers on site, to reduce the impact on the neighborhood environment and for safe removal of debris. Demolition poses a risk to not only the workers but also to adjacent structures, their occupants and other people nearby. Before initiating the demolition, proper pre planning and preparation of a stability report will be handed out. After choosing the right method for demolition, it is carried out smoothly along with all the safety requirements. In olden days small structures such as houses usually consist of only two or three stories, demolishing them is rather an easy process. They are pulled down manually or mechanically using hydraulic equipment mounted on cranes, excavators or bulldozers and with the help of scaffoldings. Larger structures require the use of wrecking ball, heavy weight on a cable that is swung by a crane into the sides of the building. Nowadays numerous numbers of methods have come up such as cut and take down method, hydrodemolition, demolition by explosives, demolition by non- explosive cracking agents etc. Importance of Debris management should be realized and adopted everywhere, especially before a predicted disaster. Dust management is essential and this plays a major role in air pollution, therefore we should aim to manage and overcome it. 2. PRE DEMOLITION PROCESS Every structure has an expiry year, existence of the building after its life is very dangerous.Surveying of the building, structure and surrounding is carried out. The record drawings and structural drawings are read and information regarding the construction materials used, shared facilities with adjacent structures, sensitivity of the neighborhood with respect to noise, dust and traffic is gathered, method of construction and deterioration of structural elements are also obtained. Presence of chemicals, explosives or petroleum etc. is noted or even if the building was previously used to store chemicals it is also taken into consideration for soil analysis. http://iaeme.com/Home/journal/IJCIET 359 [email protected] Muthu, Venkatasubramanian, Aparna Balasubramania Sharma, Snehalatha S and M Kazalli Decisions are made about the method of demolition to be used and the types of equipment, plant, labor etc. that has to be used will be analyzed. The plan in detail mentions the sequential procedure of demolition and finally states the precautionary measures that will be taken. It also mentions about their debris management plan as well. A stability report is provided based on building administration regulation and it contains the steps taken for the stability of the structure at different stages of demolition, Structural calculations for requirement of temporary supports or bracing are stated and stability of the adjoining structures and buildings are also reported along with calculations for the requirement of temporary and permanent supports for these adjacent structures. Most importantly it ensures that throughout the procedure, the margin of safety will be maintained well within the limit. Finally the safety precautions taken are reported which assures that the equipment are inspected regularly, there is access to a properly connected power source, all flammable goods are removed and firefighting appliances are maintained in good condition, only trained workers with full safety measures are allowed to do the job, emergency exits are provided during demolition, adjacent buildings are safe from the vibrations and that possible steps are taken to reduce to impact on environment. Most importantly it contains the steps taken for the safety of workers on site particularly against exposure to dust, chemicals, heat and noise. Medical attention has to be also assured. 3. BASIC DEMOLITION METHODOLOGIES ADOPTED Various methods for demolition have been adopted along with industrial evolution. The following are some old and new methods applied in practice. 3.1. Jack Hammer Figure 1 Jack Hammer Jack hammers is a combination of hammer and chisel that are hand operated or machine operated, powered by compressed air or electric motor. Nowadays they are mounted over construction machineries such as excavators and cranes and are used for demolition by hydraulic operation. This is called top- down method of demolition. The different types of jackhammers used for demolition are Pneumatic, Electromechanical or Electro pneumatic and Hydraulic. It if used for demolition of concrete, rocks and pavement. It is possible to remove even the concrete with the rebar. It is the most economical method for demolition and thus it can be used in projects where the initial cost is less. If the user is very skilled and strong, he/she can support the weight of the tool and demolish easily. Sometimes two experienced labors team up and finish the job quickly. But the machine operation is noisy and creates micro cracks on the undamaged portion of concrete. Vibrations will weaken the bond between undamaged concrete and increases the chances for corrosion and damages in rebar. It also leaves behind 10-20 mm of dust making it http://iaeme.com/Home/journal/IJCIET 360 [email protected] Safety Management during Building Demolition-A Study impossible to lay the new concrete over it because if it is done so, it will have very weak bonding. Scaffolding, netting and sheeting is provided for protecting nearby structures and people. A normal building floor will not have the capacity to withstand the weight of a heavy crane and the dismantled waste materials so they are reinforced first.