Innovation: Key to sustainability
Organisation for economic cooperation and development estimates that a minimum of $50 trillion of investment in infrastructure will be required to fuel global development. India being a developing country will need between 700 and 900 million sq m of new housing space annually. One material that would be used in huge quantities to develop the required infrastructure and housing would be concrete. Huge quantities of natural materials mined and processed for making concrete is expected to leave a substantial mark on the environment. The enormous amounts of energy required to produce cement and aggregates to cast the required quantity of concrete releases large quantities of carbon dioxide into the atmosphere which damages the environment thereby increasing global warming leading to climate changes. Therefore sustainability in construction continues to be the topmost priority. To achieve this, innovation plays a major role in enhancing the quality of constituent materials which in turn increases the life of a concrete structure. Business models fostering innovation has helped the cement and concrete industry to evolve as can be seen by the trends in advances in the manufacturing process of cement and various types of concretes that is cast at site.
Cement & concrete
Cement continues to play a critical role in the global economy and is considered to be a barometer of growth in the development of nation. Various types of cements are being manufactured which is being used in combination with other ingredients to make concrete - the major building block of structures that fulfill various functional requirements. It is widely accepted that concrete is the most widely used material for construction. Romans are credited for the invention of cement-based concrete. They built several monumental structures like Pantheon in Rome which survives to this day. The word concrete is derived from the Latin word ´concretus´, which means growing together. Concrete is generally cast at site or at an RMC plant. Its huge popularity is the result of a number of well-known advantages such as high compressive strength, general availability, and wide applicability. But due to various developments it is seen that that concrete can be produced in ways that can minimise its harmful impact on the environment. To balance various requirements of quality, functional requirements and environmental friendliness, innovation plays a vital role.
Innovation as per literature is the ability to bring together ideas that are original in nature and helps in application of solutions that meets the needs of stakeholders. Adoption of an innovation is possible if it is having relative advantage over the next best option and the users are convinced that it improves their present situation. Improvements or changes as a result of innovation could be in any of the functions, which results in effective after-sales service, integration of various functions, local adaptation, increasing the service life, enhancing the productivity, ensuring that the impact on environment is minimum, reducing completion time and enhancing quality
Figure 1: Innovation for Sustainability
Sustainability as per Brundtland report is based on the principle of the ability to meet the needs of the present without compromising the ability of the future generations to meet their needs. The challenge before cement industry for sustainability is enormous as it uses raw materials and energy that are non renewable; extracts its raw materials through mining and is used by the construction industry in making concrete which in most of the cases is not being recycled. There are a number of initiatives to achieve sustainable growth that has been taken by the industry. Kilbert explains sustainable construction as the creation and responsible management of healthy built environment based on resource efficient and ecological principles.
Sustainability is getting more importance in view of the following trends:
- The country´s infrastructure is expected to grow as India is a developing country
- Natural resources for manufacture of cement and concrete are getting scarcer
- In view of the huge quantities of cement and other constituents that is required to make concrete, emissions are expected to go up leading to global warming.
Increasing number of certifications for green buildings
Innovation in construction makes green building a reality. Green building based on sustainable practices is the one which is energy efficient, conserves water and natural resources, recycles wastes and therefore considered to be healthy than a normal building.
The practices that promotes sustainability must be implemented at every stage of the project starting from design stage to the execution stage and thereafter during the maintenance period.
It is interesting and encouraging to note that as per US Green Building Council India ranks third among top 10 countries for LEED (Leadership in Energy & Environmental Design) outside the United States.
As shown in Figure 1, innovation in the specific areas mentioned below will continue to play a major role in achieving the goal of sustainability:
1.Research & development
2.Adoption of latest technology for cement manufacturing
3.Measuring durability of concrete to enhance the life of concrete
4.Use of blended cement
5.Use of recycled aggregate
6.Customised concrete based on site requirement
7.Activities to promote good concrete practices at sites
8.Transforming the business models to foster innovation
Role of R&D: Research & development in the area of cement and concrete is pivotal as it helps in the upgradation in quality of cement, utilisation of various blending materials and also help the concrete technologist make an optimum concrete mix. R&D in cement and concrete helps the customers in various ways some of which are as follows:
1.The cement that is most suitable for a particular application. For instance if SRC (Sulphate resistant cement) is specified only on the basis of sulphates present without analysing the quantity of chlorides, it could lead to durability problems as a concrete made with SRC may not be able to resist the attack of chloride
2.Optimum mix design: Application of scientific principles to determine the proportions of ingredients to make a good concrete.
3.Cement admixture compatibility: Concrete trials conducted in a laboratory with various admixtures can be used as a guideline to monitor the compatibility at site
4.Measurement of durability helps the project personnel to decide the type of concrete and the degree of durability required for a particular application.
Adoption of latest technology for cement manufacturing: Innovations in the area of cement manufacturing has lead to numerous technological developments in the following areas :
- Energy efficiency
- Use of alternative energy sources
- Optimal mix of modes of transport to deliver raw materials and cement with a view to decrease emissions
- Quality assurance to ensure quality in cement
- Increasing usage of blending materials for conservation of limestone resources
- Installing pollution control devices to arrest emissions
- Safety and worker health conditions
- Mining practices
Measuring durability of concrete to enhance the life of concrete structure: The ability of concrete to withstand damaging effects of environment thereby enhancing its service life is durability. While evaluating the durability of concrete one should take into consideration the environmental factors affecting the concrete and accordingly adopt innovative techniques to resist those factors.
Extensive amount of research and trials have been carried out to understand the mechanism of deterioration due to which basic information and knowledge about concrete durability is available. There are instances of premature deterioration of concrete structures, which increases the costs to the economy and it is clearly evident that in most of the cases that knowledge is not applied adequately.
The challenge then is to utilise and transform these information into good practices at site where measurement of durability can and should be incorporated at the site if priority is given to the life of concrete structure.
Durability of concrete is dependent upon the quality of constituent materials , the practices adopted to mix concrete at site and the post concreting techniques. Sometimes concrete having just high compressive strength may not enhance the service life of a concrete structure. The type of cement and the concrete mix used must take into account factors affecting the durability of concrete structures like the exposure condition, type of structure, the type of attacks the concrete may be subjected to which may be sulphate/chloride attack, alkali aggregate reaction.
Compressive strength of concrete are being measured at sites which can encourage sustainable construction. Durability can be measured through tests like RCPT (Rapid Chloride Penetration test) or the water permeability test.
If the concrete structures have a long life and is durable, there could be large savings in natural resources and energy. By extending the lives of most of the concrete structures, the resource efficiency can be increased. The use of high performance concrete and various types of customised concretes, proper use of additives and admixtures in concrete, protective coatings have contributed in increasing the life of concrete structures. The danger to life of concrete structures at site may be attributed to fast track construction methods without due consideration to quality assurance measures. If the owners seek a durable concrete structure with a longer life they must follow a life cycle cost approach rather than deciding just on the basis of lower initial cost.
Use of blended cement: Cementing materials like fly ash and slag are being increasingly used in concrete to enhance durability. One of the major challenges facing the concrete industry is the selection of the right quality of blending materials. The difficulty in selection and testing of such blending materials can be overcome through the usage of blended cements like Portland Pozzalona or Portland Slag cement where the right quality of blending materials as per the codal specifications are used to manufacture these cements.
The cement and construction industry have realised the importance of supplementary cementitious materials like fly ash, ground granulated blast furnace slag from a qualitative perspective. These materials with Pozzolanic or hydraulic properties when added to cement improves properties of concrete in fresh and hardened state. The workability, the long term strength and durability of the con-crete is improved.
For usage in the manufacture of blended cements, these blending materials should satisfy the require¡ments as stated in the code for fly ash - IS 3812 and that of slag û IS 12089.
Use of recycled aggregate: Many construction projects in Europe, America and Asia have started using recycled aggregates. This is beneficial and necessary from the perspective of environmental preservation and effective utilisation of natural resources. In our country the concrete technologists should be encouraged to conduct more number of concrete trials with recycled aggregates. Recycled concrete aggregates is different from natural aggregates as recycled aggregates is generally composed of two different materials - natural aggregates and cement mortar attached to it. The results of such concrete mixes with recycled aggregates needs to be compared with concrete made of natural aggregates with respect to properties like slump & compressive strength, which will help the project personnel take appropriate decisions on the optimum percentage of recycled aggregates.
Customised concrete based on site requirement: Concrete which is hard, strong and durable by the user is only achieved after it goes through a stage of plasticity but the attention paid to fresh properties of concrete is small, despite the far-reaching effects of inadequate fresh performance.
Pumping, spreading, moulding and compaction all depend on rheology and thanks to an increasingly scientific approach it is becoming possible to predict fresh properties, design and select materials and model processes to achieve the required performance. Rheology is now seriously considered by users, rather than being seen as an inconvenient and rather specialised branch of cement science.
Rheology as per literature from concrete technology is the science of the deformation and flow of matter, and the emphasis on flow means that it is concerned with the relationships between stress, strain, rate of strain, and time.
A performance-based concrete quality control during concrete construction with documentation of achieved construction quality and compliance with the specified durability should also be carried out. When the concrete structure is completed, the owner should further be provided with a proper service manual for the future operation of the structure.
Various types of concrete like self compacting concrete, light weight concrete, high density concrete are being used for some of the projects in our country. Experts in concrete technology have been advocating the importance of performance specifications as against prescriptive specifications. Prescriptive specifications provide a set of detailed instructions and ingredients to make a concrete which inherently is non innovative and performance specifications place emphasis on the requirements of the final product, i.e., concrete. Performance specifications encourages innovative practices as the concrete technologist is given the freedom to decide the proportions without compromising on the quality of concrete.
Activities to promote good concrete at unorganised sites
Levitt (1972) radically suggested that "There are no such things as service industries. There are only industries whose service components are greater or less than those of other industries. Everybody is in service."
This suggestion of Levitt applies to cement and concrete sectors. Cement in most of the cases is being used in combination with other ingredients to make concrete or mortar and therefore the practice followed by the construction personnel determines the quality of concrete. The concreting work in majority of the small sites is carried out by skilled labour without much conceptual knowledge in concrete or by unskilled labour. Therefore services in the form of awareness programs or assistance to the personnel working at site to make a durable concrete assumes importance. Engineers need a ´sustainability design framework´ that can guide designers through the necessary steps of sustainability design. Coordination between owner, concrete manufacturer, contractor and consultant to ensure that each play an effective role in the implementation of the project to emphasise on parameters enhancing durability and sustainability.
Transforming the business model to foster innovation
Osterwalder et al. (2005) defined a business model as a conceptual tool that contains a set of elements and their relationships and allows us in expressing the business logic of a specific firm. Changing the business model for a company may imply a change in the operation or skill set of its various functional department and its relation to external resource or knowledge. The business model must be able to incorporate all routine measures and technology needed to implement a green construction which fulfills the criteria of sustainability. The knowledge that is required to incorporate sustainability in construction is unique and it is not easy to imitate, and hence ways and means to encourage innovative practices are to be incorporated into the business model. Business model must take into account the customer segment that it wishes to serve, value proposition and the revenue. The ability to foster and transfer innovative products and services is one of the prime criteria that is to be included in the business model.
A business model encouraging effective coordination between different functions is the most effective as sustainability is considered to be an interdisciplinary approach picking up insights from disciplines like engineering and science, sociology, geology, management and psychology. Therefore it is important to bring professional opinions together specifically with regard to green technology and techniques, reliability and quality of specification, leadership and responsibility, stakeholder involvement and guide/benchmarking systems.
An effective business model must ensure involvement and cooperation of all parties who are involved in a construction project as subcontractors or suppliers as without cooperation and involvement of the partner network, successful implementation of green specifications which lead to green construction seems difficult, if not impossible.
Sustainability needs to be approached holistically which could be achieved if innovative techniques are encouraged and incorporated in the business model. India with a long coastline of about 7,500 km makes it more prone to risks arising out of climate change and hence there is an urgent need to innovate to achieve sustainable growth in concrete construction. The average global temperature and indeed in some places the local temperatures are seemingly rising some say by one or more degrees over the last century, as documented by several sources. Although climate challenge is a global challenge it is on our capacity to create local solutions that will help us to redress this challenge. A rising trend in certifications by LEED (Leadership in Energy and Environmental Design) or Green Building Rating System India may pave way for more number of innovations. A viable balance between growth of the infrastructure and optimum use of resources is the need of the hour and hence requires urgency in implementation.
- Kibert, C J (2005) Sustainable Construction: green building design and delivery. New Jersey: Wiley.
- Brundtland Report Our Common future
- Osterwalder, A, Pigneur,Y and Tucci,C L (2005) Clarifying Business Models:Origins, Present, and Future of the Concept, Communications of the AIS, 16(1), 1-25.
- Levitt, T., 1972, Production Line Approach to Service, Harvard Business Review, September-October, pp. 41-42.
- Sunil Mathur, All things smart and wonderful (August 29, 2015) - Business Line dated August 29, 2015.