Roller Compacted Concrete For Pavement Applications

Roller Compacted Concrete is an innovative technology gaining popularity in the recent past due to some of the positive points like low cost of construction, speed in construction, and the possibility of using mineral admixtures obtained from industrial wastes like Fly Ash and Ground Granulated Blast furnace Slag (GGBS).

Dr. S. Krishna Rao, Professor and Head - Civil Engineering Department, Vignana Bharathi Institute of Technology, Hyderabad

Roller Compacted Concrete (RCC) has been developed as a new construction material during the 1960s for dam applications. ACI 325.10R defines Roller Compacted Concrete as concrete compacted by vibratory roller. By definition it is simply a concrete mix that has a stiff consistency (Zero Slump) which enables it to spread with a special type of paver and which can be compacted under the wheels of vibratory roller. RCC can be placed without formwork at large production rates and can be considered as more economical than conventional pavement quality concrete which is used in rigid pavement applications.

Material properties of RCC have a wider range of variation than the pavement quality concrete. Ordinary Portland cement of different grades, PPC and PSC, different mineral admixtures like Pulverised fuel Ash, Ground Granulated Blast Furnace Slag etc., and aggregates not satisfying the grading requirement usually for normal or conventional concrete can be used for its preparation. RCC can be used for pavement applications and this new paving method was proposed to be the best cost-effective and durable solution for rigid pavements and similar applications.

Roller Compacted Concrete Pavement (RCCP) material was successfully used in Canada in heavy industrial areas under severe frost conditions. The material had been doing well for carrying heavy traffic wheel loads with low construction cost. After that experience, several advances have been introduced to RCC. Most of these advances are focussed towards improving quality of the surface and durability. Also, an improvement in rideability came when special pavers were employed for placing the RCCP. With the advent of this procedure, RCC now unites the quality of concrete material and the low cost of bitumen and construction procedure of the bituminous pavements.

Roller Compacted Concrete For Pavement Applications

The low water-cement ratio varying between 0.30 to 0.40 assists in providing very high strengths. RCCP material is placed without formwork, with no surface texturing and no finishing. Hence it can be constructed very rapidly requiring less labour than traditional pavement quality concrete (PQC). With low water content used in the RCC mixture and low water-binder ratio, RCC usually has strengths greater than conventional concrete. To satisfy the economy of construction of RCC over PQC, smoothness and surface quality of RCCP suffer.

Applications
Considering the limitations of the Roller Compacted Concrete, its major application is for industrial pavements such as:
  • Industrial access roads
  • Parking areas
  • Shipping yards and port terminals
  • Truck terminals
  • Bulk commodity storage yards
  • Aircraft Apron
  • Urban streets, rural roads and parking paths
  • Heavy commercial parking lots (Surface Car Parking)
Advantages
Roller Compacted Concrete Pavement (RCCP) has the following advantages when compared to the conventional pavements.
  • It has high flexural and compressive strength.
  • Reduction in construction time.
  • Little Maintenance costs
  • High freeze-thaw durability
  • Reduced cracking and shrinking
  • Resists abrasion even under heavy traffic loads and volume
  • It has more resistance for high temperature
  • More Durability and high resistance to chemical attack
Limitations of Roller Compacted Concrete
  • The surface of RCC is rougher than other pavements and not suitable for high speed traffic.
  • The construction of adjacent slabs and also multiple horizontal lifts in same layer shall be placed within an hour to make sure the good bonding between layers.
  • It is very difficult to compact the pavement layer towards the edges and hence most specifications are forced to limit the percent compaction to 96% modified proctor density.
  • Generally, the use of admixture on RCC may be higher than conventional concrete pavements because of the dryness and stiffness of the mixture.
  • In hot weather concreting of RCC for paving requires additional attention to decrease the possibility of water loss due to evaporation.
Considering the versatility of RCC over conventional pavements and its ease of application and its durability as compared to traditional bituminous pavements it becomes clear that the roller compacted concrete is a suitable paving material. Also, when considering the ever-increasing cost of petroleum-based products such as bitumen it becomes quite evident that RCC is likely to be the paving construction material of the future.

Roller Compacted Concrete Pavement Construction Procedure
Roller Compacted Concrete For Pavement Applications

Connectivity of rural roads is an important criterion in rural development. Low volume rural roads in India, including other district roads (ODR) and village roads (VR), occupies about 80% of the total roads of the country. At present these roads are provided with asphalt pavements. Most of these roads are potholed and distressed due to variety of reasons. Therefore, there is an urgent need to construct and maintain the rural roads in an optimal manner.

Alternative Solutions
A place where soil is soft and of poor strength, aggregate is costly and poor drainage conditions are prevailing; rigid pavement is best alternative to flexible pavement. Rigid pavement of following types is suggested in place of flexible pavements:
  • Plain Cement Concrete Pavement (PCP) with M-30, M-35 & M-40 Grade concrete
  • Continuously Reinforced Concrete Pavement (CRCP)
  • Roller Compacted Concrete Pavement (RCCP)
Table: Some features of Rigid Pavements
Type of Rigid Pavement Features
PCP More number of joints and it causes inconvenient to the road user.
CRCP Reduces the need of expansion and contraction joint and thus improves riding quality and reduces the maintenance cost.
Construction is difficult.
More costly and involves more man power.
RCCP Overcomes the problems of traditional pavements.
Much quicker to construct.
Similar kind of ingredients as that of PCP.
Higher percentage of Fine aggregate allows tight packing and consolidation.
Rigid pavements consist of a number of joints, which reduces stresses caused due to temperature changes and this is a principal cause for inconvenience to the road users. IRC: 101-1988 specifies technique of continuously reinforced concrete pavement which reduces the need of expansion and contraction joints; and thus improves riding quality and reduces the maintenance cost compared to plain cement concrete pavement (PCP). For the construction of conventional Continuously Reinforced Concrete Pavement (CRCP), percentage of steel required is 0.7-1.0%. Provision of steel reinforcement is important to arrest the cracks that occur in the concrete. Compared to flexible asphalt pavements construction, the process of construction of reinforced concrete pavements is difficult and costlier and involves more manpower.

RCC can overcome the problems usually encountered with flexible asphalt pavements or conventional plain or reinforced cement concrete pavements. RCC is the commercial name used for concrete placed with conventional hot mix asphalt paving equipment, then compacted with vibratory rollers. The strength properties of RCC are similar to that of a conventional concrete and consists of the same basic ingredients as conventional concrete; but RCC is dry mix made with lower water cement ratio and consists of mixture of dense graded aggregates, cement and water. The major difference between RCC mixtures and conventional concrete mixtures is that RCC has a higher percentage of fine aggregates, which allows for tight packing and consolidation.

The material is carried in dump trucks, placed into an asphalt-type paver equipped with a standard or high-density screed and then compacted under steel wheel rollers. Steel Drum Finish Roller with smooth rubber rear wheels and a vulcanized rubber drum is used to produce final surface texture. The time required for placing and compaction process is critical to obtain adequate density, strength, and smoothness of the finished RCC pavement. The concrete is placed and compacted fresh and at workable stage i.e., usually within 60 min of delivery. Due to stiff consistency it remains stable under vibratory rollers, yet wet enough to permit adequate mixing and distribution of paste without segregation.

Structural behavior of RCC is similar to that of conventional paving concrete, and so the design procedure follows the methodology used for concrete pavements.
GAEPL Achieves Record Paving of 100 lane-km in 100 hours
Ghaziabad Aligarh Expressway Private Limited (GAEPL), under the guidance of Cube Highways, has set an example of speedy, safe, and sustainable road construction through research, integration of advanced technology, following best international practices

Read more ...

Indian Companies Delivering Projects Overseas
External affairs minister S. Jaishankar during his visit interacted with the workers and the senior staff, and lauded the role of Indian infra companies, saying that he was “impressed by their enthusiasm”. “Strong economics will complement shared values in taking

Read more ...

NHAI awards 6,003 km of highway projects in FY23
According to Motilal Oswal Financial Services, the infra project awarding activity picked up and gathered pace in Q4 of FY23, with NHAI awarding total projects of 6,003 km in FY23, much below its FY23 target of 6,500 km. The total value of projects awarded

Read more ...

Is the Indian Road Sector Navigating a Smooth Journey?
This report covers the current state of the Indian Road Sector, performance of road projects under Hybrid Annuity Model, financial performance of major road developers, and the outlook for FY24. CareEdge Ratings analysed 235 HAM projects awarded between

Read more ...

Balanced Mix Design for Bituminous Mixes
As more than 90% of the roads in India have bituminous surfacing, a proper bituminous mix design also assumes significance for better performance of the bituminous roads. India is currently witnessing huge investments by the Indian Government towards

Read more ...

Sustainable Road Construction in Hilly Region
Siksha Swaroopa Kar, Principal Scientist, Amit Kumar, Technical Officer, Krishan, Technician, Flexible Pavement Division, CSIR-CRRI, New Delhi, discuss mechanized laying of cold bituminous layer, the mixer and paver that have been fabricated, and the effectiveness

Read more ...

Implementation of Road Maintenance Management System - Benefits & Technologies
The maintenance of road pavements is essential to ensure the safety, reliability, and sustainability of road networks. A road maintenance management system (RMMS) involves effective management of resources to optimize the life cycle of roads, reduce maintenance

Read more ...

Replacement of Steel Reinforcement with  Synthetic Fibre for Concrete Pavement & Floor
Manoj Didwania, Adani Total Gas Ltd, Dharamsinh Desai University (DDU-Nadiad), Cept University, presents a paper on the use of Macro Synthetic Reinforcement Fibre (MSRF) as full or partial replacement of Steel Reinforcement for Concrete Pavement

Read more ...

GTI® Reinforced Soil Slope System
GTI® is involved in developing environmentally friendly construction products and systems, which are critical for achieving infrastructure growth in a sustainable manner. The company’s GTI® Sloping Fascia Unit and the new system GTI® Reinforced Soil Slopes

Read more ...

CRISIL: Debt to rise for road developers amid strong revenue growth
Sizeable equity commitments in under-construction projects and rising working capital requirement will increase the debt burden of road developers, though revenue growth will also be high in the next two fiscals driven by strong awarding and execution

Read more ...

Indian Toll Roads to witness moderation in growth to high single digits in FY2024 after a stellar 17-20% growth in FY2023: ICRA
WPI for December 2022 is significantly lower at 5.0% against WPI of 14.27% in December 2021. ICRA Ratings expects the toll road projects growth to moderate to high single digit in FY2024 after a 17-20% growth witnessed in FY2023 with moderation in the

Read more ...

Road Over Umling-La Pass at 19,024 Feet
Construction of World’s Highest Motorable Road Chismule – Demchok In Eastern Ladakh Using Non-Frost Susceptible Sub-Base. Union Territory of Ladakh is located at approx 11,000 feet above Mean Sea Level (MSL). The area experiences extreme cold

Read more ...

BRO Uses Eco-Friendly Steel Slag For Road Construction
Steel slag, a by-product of steel making, is produced during the separation of the molten steel from impurities in steelmaking furnaces. This process generates slag as a molten liquid melt and is a complex solution of silicates and oxides that solidifies

Read more ...

Potholes to become history breakthrough by Zydex
Vadodara-based Zydex Industries has developed a new technology in road construction that enables roads to resist cracking under heavy traffic loads and cyclic weather variations. The speciality chemicals company has been at the forefront of R&D and implementation

Read more ...

Expected Increase in M&A and Refinancing Activity for HAM Projects in India: ICRA
According to the ratings agency ICRA, there is expected to be an increase in mergers and acquisitions (M&A) and refinancing activity in highway asset management (HAM) projects in the upcoming quarters. Approximately 105 HAM projects, with a total bid project

Read more ...

Prestressed Precast Concrete Pavement (PPCP)TM
PPCP Technology can help build roads of good quality, which are highly durable, can be built quickly, and do not require extensive maintenance. The construction industry is primarily concerned with two issues: construction quality control and the speed

Read more ...

More Efficient Road with iROADS Asset Management
iROADS Asset Management System enables significant optimization of road maintenance costs while ensuring a well-maintained road network and road assets. India has the second largest road network in the world comprising national

Read more ...

Upgradation of PMGSY Road Using Full Depth Reclamation Process in the State of Nagaland
Rapid growth in industrial development and economy in last two decades has demanded upgradation of the existing road network in the country. Though there is a huge road network in the country, it is still inadequate to meet accessibility and mobility requirements

Read more ...

Erosion Control for Green Highway Construction
Namrata Bichewar, Regional Manager - Maharashtra, Gabion Technologies India Pvt Ltd, discusses the company’s contribution in constructing green highways using Bio-Engineering Erosion Control methods and solutions. The government plans to construct 26 green expressways

Read more ...

Stone Matrix Asphalt is enabling durable and maintenance-free roads in India
A Stone Matrix Asphalt (SMA) pavement laid at Parimal Underpass in Ahmedabad Municipal Corporation has completed 7 years. The underpass, which used to get submerged under almost 2m depth of water due to waterlogging in the monsoons every year

Read more ...