Thursday, October 19, 2017

Cover Story

Vertical Challenge

 

August, apart from being the month of the annual Independence Day jamboree, has seen celebrations galore for real estate fashionistas in Upper Worli, dubbed Mumbai’s new Golden Mile.

The reason being the announcement of a new skyscorcher – a 75 storey, 800 ft Trump Tower announced for construction by real estate mogul, investor and television personality Donald Trump in association with India’s Lodha Group, which prides itself as the country’s No 1 luxury real estate developer.

 

Global Supertalls: QUICK FACTS

  • Tallest Building: Burj Khalifa: 828 m
  • No of Supertall buildings: 82
  • No of 200 meter+ buildings: 861
  • No of 150 meter+ buildings: 3038

 

Abhishek Lodha, Managing Director, Lodha Developers, a mumbai based firm, which is currently developing over 35 million square feet of prime real estate in Mumbai, Pune, Hyderabad and London, is wont to talk of the project in terms of it “redefining the Mumbai skyline”. That may very much be so. The Trump Tower which comes at a price tag of $80-100 million will include 3-4 bedroom residences with indoor jacuzzis. An added bonus will be a membership of a private jet service.But it is not just Donald with his uber luxury style statements wrapped into real estate which will be a trump card for India’s commercial capital. The Lodhas are already on the way to make a real estate sky statement when their iconic 1450 ft residential supertall, World One, gets completed sometime in 2015! It is not difficult to see why, what with the world’s greatest names in architecture, interior design, structural engineering, landscaping and vertical transportation – Armani/Casa, Pei Cobb Freed, Ken Smith and Barker Mohandas – associated with the project.

Understandably, construction firms are now expected to get busier with structures all set to challenge the skies – and not just in Mumbai but in New Delhi, Gurgaon, Noida, Ahmedabad,  Pune, Hyderabad and Bengaluru. The opportunity for business is huge. So much so that contractors like Mumbai based Capacit’e Infraprojects – which is doing a host of projects for major real estate majors like Hiranandani, Ramprastha, 3C, Emaar MGF and the Lodha Group (it has bagged the work for the Trump Tower) have emerged as the new high rise specialists.

 

Rahul Katyal, Managing Director, Capacit’e Infraprojects, is led to say, “We are mainly focused on the high rise segment that is because we see a big need and opportunity there. In the coming years close to 50 per cent of the population of India will be urbanised. With that happening, no building in Mumbai will be less than 50-60 floors.”

 

 

“Cities like Mumbai have little choice but to take the vertical route. We remain extremely focused on high rise projects,”  says Gagan Banga, Vice Chairman and Managing Director, India Bulls Housing Finance Limited, one of the country's leading business houses with interests in housing finance, real estate, securities, construction equipment leasing and facilities sector.

If Mumbai’s structures are heading north, the Delhi NCR region too is witnessing a high rise leap. Sensing the scarcity of land the area is likely to confront in the not too distant future, builders and developers are focusing their attention on high rises and skyscrapers.

 

“It is as if there is a race to build tall,” observes Dr Sunit Sachar, Sr.Vice President (Mktg, CRM & Advt), Parsvnath Developers Limited. “With land getting scarce by the day, urbanisation on the rise, slow pace of infrastructure developments, constraints of spreading horizontal due to cost inflation and ever increasing population going vertical remains the only answer.” 

Raheja Developers Ltd which has delivered approximately 29.5 million sq ft of mainly residential and commercial projects too is scorching the northern India skyline through its landmark high rise projects, the 195 mtr, 56 floor Raheja Revanta in Gurgaon and the 190 mtr, 54 storey Raheja Phoenix in Delhi. There are other players like Supertech, Assotec and 3C which are constructing supertalls in Noida.

 

“With the government’s  agenda to build small 100 smart cities, constructing high rise pre-engineered structures with steel will be a natural choice,” avers Sanjay Dutt, Executive Managing Director, Cushman & Wakefield, South Asia

Prime Minister Narendra Modi’s dream project – Gujarat International Finance Tec-City aka GIFT City – being built on barren tract of land near the state’s capital Gandhinagar is already seeing a frenetic pace of development. With two of the tallest buildings in the state already constructed in the zone the financial hub will in the final analysis see as many as 120 high rise buildings, including international hotel chains, malls, hospitals, entertainment zones and a landmark skyscraper called the Diamond Tower, leaping up from a total built up area of 62 to 90 million sq ft.

 

Says Ramakant Jha, Managing Director, Gujarat International Finance Tec-City, “The idea is to make this the best Smart City in the world. We are building high rises since we have to package that smartness within a small geography. We have the best of players involved in the exercise from design to implementation stage.”

While GIFT City could be regarded as an initiative of the state such high rise ambitions, albeit on a miniscule scale, are reflected in a community based cluster development at Bhindi Bazaar in south Mumbai. The Bhindi Bazaar Redevelopment project will see the dilapidated building zone being transformed into a smart Manhattan.

 

Abbas Master, CEO, Saifee Burhani Upliftment Trust, the organisation which is spearheading the area’s change of avatar, says, “Going forward we see the possibility of people in other areas replicating our programme with the high rise approach.”   

It is easy to see that India is not just thinking big; it is thinking tall as well. While shortage of space is the raison d’ etre for vertical developments, the aspirational aspect of it – of having a home in the clouds – cannot be underestimated. Quite revealingly last month saw the release of a report which said that India’s growing elite, those worth in excess of $3.75 million grew by 16 per cent in 2013, and that the country’s rich would quadruple their net worth in the next four years.

 

THE CHALLENGES

Ergo, there is no choice for cities but to take the vertical route.  But all of such development comes with numerous challenges. Naveen Raheja, CMD, Raheja Developers Ltd and Chairman, NAREDCO, is only underlining the obvious when he says, “Building supertall buildings requires special skills.”

It would be fair to say that though India, notably Mumbai, has its fair share of skyscrapers, is still in the teenage of high rise development. Much of this stems from the fact that supertalls require highly advanced technology and techniques which Indian developers have not yet experimented with partly because of the cost factor. Admittedly Indian structural engineers have earned encomiums from working on some of the iconic super tall projects abroad – this including the Burj Khalifa in Dubai and others in the Gulf – but their imprimatur is yet to be seen at home. Most Indian real estate developers and contractors rely on foreign expertise – designer- architects, structural engineers, and project management experts – in their construction. 

 

Says Matthew Grant, Director, High Point Project Management Solutions Private Limited, a Mumbai based project management consultancy which counts developers like Lodha, Omkar, Ahuja, Capacite, Shapoorji Pallonji amongst its clients, “India is still at the learning curve and there is a lot of work to do. Not enough time goes into the planning and detailing of projects” 

Grant, an engineer, should know having worked on iconic high rise projects like the Kingdom Trade Centre and the Faiseleh Tower in the Middle East whilst working for Buro Happold previously. He now helps Indian developers and contractors develop a construction efficiency programme and in implementing project management techniques and systems within their companies. Says he: “India’s workforce needs to be trained. We may not be able to operate as quickly as say the man in the Middle East, we probably don’t have the same level of skills as the man in New York or Tokyo, because we are not used to doing things with high performance technology. For instance, a climbing form system is still not very common in India. What we have to do there before starting work is to understand the qualifications of the workforce.”

 

If Grant is diplomatic, Chetan Raikar, Chairman & Managing Director, Structwel Designers & Consultants Pvt Ltd, is more critical. “There is a mad rush to build tall buildings without preparedness and knowledge on all fronts. There is need to bridge the technological gap between us and the developed countries. Building 20 floors, or even up to 35, is currently our comfort zone but beyond that calls for special expertise, proper project planning and management. Experience is definitely needed in the construction of supertall buildings.”

Admittedly there are problems associated with non-availability of trained man power, the quality of material used in construction – high grade concrete of M60 and above is required the case of supertall buildings and this necessitates back up and support of the RMC people to pump concrete to the heights – the perils of the high rises coming up in congested areas with poor approach infrastructure restricting movement of workers, materials and construction equipment like cranes to the job site. This is also further compounded by safety issues. What is something dropped from the heights? 

Tall buildings have other limitations too. Not only do they require a proper design they also they have to be equipped with special building skin to keep the buildings maintenance free. Although provisions are made for fire fighting, sprinklers and  other equipments, it still does not absolve the risk of fire fighting on higher floors as government fire fighting equipments has small reachable range. Also in India, there is the constant risk of disrupted power supply.  Hence a very high level of dependence would be required on alternate generation electricity. Tall buildings cannot afford to risk of non supply even for few seconds irrespective of the cost.

“Care must be taken that we go vertical in keeping with known limitations, concerns and choose the heights of buildings with prudence,” says Parsvnath’s Sachar.  

There is also the issue of a serious lack of preparedness which needs to be addressed. Matters like work facilities, maintenance, repairs and demolitions, disaster management plan require to be factored at the planning stage itself. “There is not much planning and preparation going into projects. We need a next generational change both in our thought process as well as in the techniques we employ. We need professionals with vision to handhold till we can take care of ourselves,” recommends Raikar.

But much before the actual construction of high rises developers have to encounter the uphill climb of having to obtain multiple permissions, a tedious process which lead to delays in construction and consequent escalation of costs “It takes almost 3-4 years to begin with the project and almost 5 years to complete the project which makes a total life span of 10 years before any high rise building is completed,’’ laments Rajendra Chaturvedi, CMD, Shreepati Group, a major player in Mumbai’s high rise firmament.

 

OUTLOOK

While the challenges of building next generation tall buildings are understandable – those can be surmounted with a combination of policy framework, technical knowhow, project management skills - high rise buildings present a great business opportunity for various players in the construction sector. This includes suppliers of readymix concrete, steel and other material, electrical and air conditioning products, safety and security gadgets, vertical transport specialists, project management software companies, green building consultants, designers, structural engineers, landscaping experts, facilities management companies, project management consultants, construction equipment like tower cranes, real estate fund managers, not to mention the various institutions as a source of trained manpower. 

Sunil Mantri, Chairman, Mantri Realty Limited, a Mumbai based real estate firm which currently includes mid size high rises – up to 30 storey buildings – in its project portfolio, is led to declare, “Whether we like it or not the future and the style of the construction business is tall and we must be ready for it.” That style and sky statement
would certainly meet Donald Trump’s approval.

 

 

 

 

Tall Cruise

It’s been a dizzying journey to the top for the Burj Khalifa, currently on the record books as the world’s tallest free standing structure. The Dubai building has during its construction cruise – beginning with excavation work in 2004 and ending with its completion in just 1,325 days, amassed a mind numbing number of facts, figures and statistics all of which reflect a combination of visionary ideals and solid science. Witness the highlights: Concrete in excess of 45,000 m3 (or 58,900 cu yd), weighing more than 110,000 tonnes were used to construct the concrete and steel foundation which features more than 192 piles buried more than 50 m deep. The building’s construction used 330,000 m3 of concrete and 39,000 tonnes of steel rebar and construction took 22 million man hours. The exterior cladding of the Burj Khalifa began in May 2007 and was completed in September 2009. The project involved 380 highly skilled engineers and onsite technicians. At the initial state of installation the team progressed at a rate of 20-30 panels a day and eventually achieved as many as 175 per day.  The tower accomplished a world record for the highest installation of an aluminium and glass façade at a height of 512 metre. The total weight of the aluminium used on the building is equivalent to that of five A380 aircraft and the total length of stainless steel bull nose fins is 293 times the height of the Eiffel Tower. The highest reinforced concrete corewalls were pumped using 80MPa concrete from ground level – a vertical height of 601metres – thus eclipsing the previous pumping record of 470 metres at Taipei 101. The amount of rebar used for the tower is 31,400 metric tonnes – laid from end to end this would extend to a quarter of the way around the world.  It is also a tribute to the spirit of international collaboration in that more than 30 on-site contracting companies from countries across the world participated in the building of the iconic structure. At the peak of the construction over 12,000 workers and contractors from more than 100 nationalities were reportedly at the site each day.

 

Super tall challenges

A number of Super High Rise Buildings are coming up in India – Mumbai in particular. Besides seeking faster completion of a larger volume of work, additional safeguards are incorporated for quality and safety in such structures. Clarity of scope, finalization of drawings, availability of applicable permissions etc. are essential upfront, to avoid costly changes subsequently.

The construction of a Super High Rise Structure entails detailed planning, robust communication and meticulous implementation of the following steps :

 

  • Drawings
  • Bill of Quantities
  • Specifications

 

  • Bill of Materials
  • Work Sequence
  • Construction Methodology
  • Project Quality Plan
  • Health, Safety & Environment Plan

 

  • Equipment Selection
  • Formwork Scheme
  • Site Logistics Plan

 

  • Construction Programme
  • Productivity Analysis
  • Resource Schedules
  • S Curve of Invoice & Cash Flow

 

Though this may seem routine as in any other construction project, the difference lies in the complexity and detail, particularly in respect of the preparatory works involved.

 

For example, the raft concrete is so deep and voluminous that the pour is spread over multiple days and in a number of layers, entailing special temperature control measures.

 

In respect of construction logistics, the arrangements for pumping concrete to the higher floors (numbering over 50 to 100), the arrangements for water supply, fire fighting, curing scheme, waste water disposal and debris management for the higher floors need detailed planning and implementation of proven systems, following on-site trials.

 

In case of Formwork, the geometry involved (simple or complex, repetitiveness or changing profiles) is crucialin selecting the technology and scheme. The rate of concrete pour, setting time and curing time, finish requirements etc. too play an important role in this. The sequence of work activities, cycle times, quality and safety considerationsinfluence the choice of formwork systems.

 

 

FORMWORK SELECTION FOR DIFFERENT COMPONENTS  IN A TYPICAL SUPER HIGH RISE

 

  • DOKA AUTOMATIC CLIMBING SYSTEM & TOP 50- FOR CORE WALLS
  • DOKA TOP 50 & CRANE CLIMBING SYSTEM- FOR SKEW LIFT
  • DOKA FRAMED FORMWORK FRAMI ECO- WING COLUMNS
  • DOKADEC 30 & DOKAFLEX OPTIMISED- WING SLABS
  • DOKA  PROTECTION SCREEN SYSTEM- END PROTECTION
  • ALUMINIUM FORMWORK- LOBBY SLAB, SERVANT ROOM, STAIRCASE
  • NON TYPICAL AREAS – CONVENTIONAL FORMWORK

 

Detailed engineering is done for finalizing the  Formwork Scheme including the technology, methods, components, drawings, bill of materials etc.

This is the most crucial element in the construction process of Super High Rise Buildings, as it weaves the construction methods, equipment usage and the finished product. Process quality assurance and product quality control requirements influence this.

The Plant & Machinery to be deployed for super high rise buildings too needs to be firmed up considering the particular requirements of extra height of working. The slab casting cycle times, load handling and reach requirements, crane hook time analysis, crane jumping sequence, wind and storm factors, signalling and communication systems etc. become important considerations in Tower Crane selection. Traffic studies, passenger load, material load and vertical lift speeds are crucial in selecting Hoists. Pumping concrete to extreme heights (50 to 100 floors) is a challenge, requiring stringent control on quality of concrete and efficient operation of the equipment.

The detailed resource loaded Construction Programme, the Site Logistics Plan, the Project Quality Plan, the Construction Methods, the Inspection & Testing Plan, the Health, Safety and Environment Plan, the Emergency Response Plan, the Hazard Identification, Risk Assessment & Control Plan, the Contingency Plan etc. all form important documentation in planning and executing super high rise buildings. Adherence to ISO certified procedures is essential in this context.

The experience and skill level of manpower deployed (staff as well as workmen) is an important determinant of the time, cost, quality and safety of construction. Acute shortage of skilled manpower as such is a matter of concern, but the requirement of experienced and skilled manpower in the nascent Super High Rise Building segment is a far more difficult challenge. Accumulation of human capital that is rich in this segment is a primary focus area, with the net widening to Middle East and beyond in search of talent.

Project planning & monitoring tools are very important to ensure smooth tracking of the resource deployment and construction work with respect to the established schedule. Specialised software such as Prima Vera and Candy enable this, augmented well by construction industry specific ERP packages such as Buildsmart for the procurement process that is quick and transparent. Internal MIS systems with quick feed of quality data are essential for informed decisions in a timely manner. 

 

SUPER HIGH RISE METHODOLOGY

  • PROJECT CONSTRUCTION SCHEDULE
  • PROJECT QUANTITIES & MATERIAL REQUIREMENT
  • ORGANISATION CHART AND ROLES AND RESPONSIBILITIES
  • POINTS TO BE CONSIDERED FOR SITE LAYOUT PLANNING
  • LOGISTIC PLAN FOR ON SITE FACILITIES
  • FORMWORK SYSTEMS - SELECTION CRITERIA
  • PREFERRED FORMWORK SYSTEMS FOR HIGH RISE PROJECTS
  • PLANT AND MACHINERY
  • MAIN FACTORS AFFECTING SELECTION OF TOWER CRANE
  • FACTORS AFFECTING TOWER CRANE DISMANTLING AND METHODOLOGY
  • FACTORS AFFECTING SELECTION OF MAN/MATERIAL HOIST
  • FACTORS AFFECTING SELECTION OF CONCRETE PUMP & PLACER BOOM
  • SEGMENTAL METHODOLOGIES AND WORK PROCEDURES
  • HIGHRISE PROJECT PLANS 

 

MAIN EQUIPMENTS FOR SUPERTALL PROJECTS:

  • TOWER CRANES
  • MATERIAL HOIST
  • PUMPS
  • CONCRETE PLACER BOOM

 

FORMWORK SYSTEMS

  • PREFERRED FORMWORK SYSTEMS FOR HIGH RISE PROJECTS:
  • SELF CLIMBING SYSTEM (ACS) OR JUMPFORM
  • ALUMINIUM SHUTTERING SYSTEM
  • ALUMINIUM DECK PANEL SYSTEM
  • CUPLOCK SYSTEM FOR NON TYPICAL AREA
  • GANGFORM FOR EXTERNAL PROTECTION

 

PASSION TO EXCEL

Capacit’e is executing Super High Rise Building projects for Lodha Developers (The Park, Trump Towers), Transcon – Sheth JV (Auris Serenity), Transcon (Tirumala Heights), Four Seasons Residence etc. in Mumbai and Paras (Quartier) in Gurgaon.

 

Capacit’e is a young company but under experienced management, that is driven by a passion to excel. A large part of the over Rs. 4000 Cr of orders booked in the past two years by Capacit’e has been in the Super High Rise Building segment.

 

A robust project delivery mechanism has been established for meeting the stringent requirements of timely completion within budgeted cost in a safe and compliant manner, rendering world class quality. Investment in state-of-the-art system formwork and equipment has been made to meet the requirements.

 

The high lows

SUBHANKAR MITRA on the downside of building high rise structures

Internationally, a building that reaches or exceeds the height of 150 metres is considered a skyscraper. Until recently, Mumbai was the only Indian city with high-rise buildings. The financial capital continues to see the highest demand for skyscrapers, as the only option to grow there is vertically. It now seems that in the coming decade, Maximum City will receive an even more cohesive skyline, with a host of projects in the race to touch the sky being constructed. The demand for high-rise buildings is certainly growing, and other cities are catching up.

Mumbai continues to have the maximum number of tall buildings approved or under construction. Development of India One - the tallest in the country - has already begun in Maximum City. It spans 126 floors and stretches up to a height of 720 metres. Apart from this, Mumbai has more than 30 such super-tall buildings ranging between the heights of 150 metres to 450 metres either at the approval stage or already under construction.

New Delhi, the capital of India, has around a dozen of such buildings coming up. They range between heights of 150-300 metres. Kolkata too is catching up with 9 such residential buildings extending to the height of 245 metres either approved or under construction.

Ahmedabad too has about 13 tall buildings which are under construction and are ranging between 200 metres to 410 metres. Hyderabad and Bangalore too are witnessing some development in construction of tall buildings for residential-commercial purpose with 2 or 3 approved projects.

All in all, this amounts to around 60 skyscrapers. Developers see such edifices as a good way to attract potential buyers - high-rise buildings are a good gambit to differentiate their offerings from the rest of the pack. However, this coin has two sides – high-rise development has its own share of demerits, too.

 

Effect on urban wind

Rise in the elevation of a building increases the distance of the wind shadow and minimizes the air flow at the street level behind the building. Near high-rise buildings, the local wind speed is high even in summer. In addition, high-rise buildings tend to create a turbulent flow of the gradient wind as a result of increasing the roughness of the boundary layer surface.

 

Increased air pollution

In summers, local wind speeds near skyscrapers are very high and troublesome. The ventilation conditions in the urban spaces and major streets with high vehicular traffic have significant impact on the concentration of air pollutants at the street level. The high velocity and turbulent wind at the street level results in the mixing of the highly polluted low-level air with cleaner air flowing above the urban canopy.

 

Effect on urban radiation

High-rise buildings absorb direct and reflected solar radiation of surrounding low-rise buildings and convert it into heat via convection of long wave radiation. However, when buildings are of different heights, the walls of the higher buildings absorb part of the reflected and emitted radiation and block a portion of the sky, resulting in reduced solar exposure and long-wave emission from the roofs of the lower buildings.

 

Increased urban temperature

Size and density of the built-up areas affect urban areas temperatures. In the congested centres of large cities, temperature levels are generally higher than in the suburbs. The largest elevations of urban temperature occur during clear and still-air nights, also called ‘Urban Heat Island'. Excessive opacity of high-rise buildings in city centres results in concentrated heat generation by high-density land use (traffic, lighting, heat exhaust) and contributes to the creation of urban heat islands.

 

Effect on night-time cooling

Nocturnal radiation is a major climatic factor that reduces atmospheric heat in urban areas located in hot, dry regions. Nocturnal radiation decreases when the density and the height of built-up urban masses increase. High-rise buildings store solar energy during the day time and release it slowly into low-speed local wind, especially at night. The vertical distance between cool winds above buildings roofs and the ground surface is long, and this results in decreased radiant cooling during the nights. Low-rise buildings that match trees heights of 12-15 meters, on the other hand, penetrate night-time ventilated cooling at the ground level and also store cool radiation through built-up urban areas.
 

Other factors

  • Tall buildings are colder in winter and hotter in summer than regular buildings, and therefore require more heating and more cooling. This is particularly true of modern glass towers. Thus, a lot of energy is required to keep these high rises functioning.
  • Exterior cleaning and maintenance of a high-rise building can be very costly and dangerous. With global warming (which causes higher wind speeds) on the rise, insurance companies often refuse coverage to maintenance companies in charge of high-rise buildings at certain times of the year.
  • High-rise buildings take longer to build, and due to rapid and heavy construction activity within the city, there is a heavy load on civic infrastructure.
  • In-high rise buildings the average construction cost per square foot is 20-25 per cent higher if the building has more than 12 floors.
  • Major modifications and/or renovations in a skyscraper are significantly more cost-intensive.
  • If a new building has to be built on the same piece of land, the number of claimants is vastly higher.

 

When it comes to our largest cities, there is not much one can do about these factors – and indeed, they are accepted as a fact of life in a city like Mumbai, which must grow vertically if it is to grow at all. Unfortunately, the areas of our cities which are in the biggest need of high rise buildings are also the ones which offer the lowest scope for remedial infrastructure measures that could reduce the impact of skyscraper development.

The author is Head-Strategic Consulting (West), JLL India

 

 

 

 




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