Conventional pavement construction relies on movement joints which can cause costly maintenance issues when used in heavy-duty industrial environments. Grant Roe discusses innovation in pavement construction and where seamless pavement is a good solution.
The joints in traditional ground-supported concrete flooring and pavements are designed to control cracking by allowing for movement. Horizontal movement is caused by concrete shrinkage and changes in temperature. Vertical and rotational forces are imposed by traversing traffic and load-weight. Joints can be costly to make and maintain, but if well-designed and constructed are effective at responding to movement and load whilst preventing unsightly cracking in most situations.
However, in heavy-duty industrial environments such as container storage facilities, under-awning dock areas, and high-bay automated warehouses, the relative inadequacy of movement joints in concrete pavement areas can cause severe problems for building owners and tenants. The reinforcement materials within the joints can be subjected to such great stress that they eventually fail, causing the pavement surface to become uneven, resulting in costly and disruptive maintenance.
Seamless, joint-free pavement construction
An innovative approach to industrial concrete pavement construction is the seamless, no-joints (“combi”) method which produces a more durable heavy-duty surface area. Offering longer-term utility to building owners and tenants than the traditional jointed pavement construction, the appearance of fine cracking is inherent to the combi design and should not unduly discourage its adoption when recommended for industrial construction projects, according to Grant Roe, managing director of Costin Roe Consulting, civil and structural engineers.
“Seamless floors are also well suited to high-bay automated warehousing designs where movement joints are generally precluded. For container storage areas it is absolutely a requirement that there are no joints in concrete pavements,” said Grant.
“The majority of warehouse construction projects do not involve large enough areas to make economic use of the heavy-duty flexible pavement option. However, there is a definite movement towards seamless concrete pavement construction for large external under-awning areas such as those designed for intensive heavy forklift activity. Conventional jointed pavements tend to suffer significant maintenance requirements where heavy forklift traffic has affected the joints.”
Seamless pavements can be designed using conventional reinforcement, or a combination of steel fibre and conventional reinforcement.
“The costs associated with seamless pavement construction are higher because the overall requirement for reinforcement is increased. There are savings compared to sawn and armoured joints, however construction joints are tied with heavy reinforcement, so it depends on the specifics of the project. The cost of seamless pavement construction is expected to stabilise as the method becomes more widely adopted. Even so, the cost of seamless pavement can be weighed against the anticipated savings on maintenance and avoidance of issues associated with conventional jointed pavement.”
Broader potential applications for seamless pavement
Costin Roe Consulting recently completed two separate external pavement projects of combi-seamless construction, both designed for heavy container use. “The results have been good,” said Grant Roe of these examples.
“We have also used seamless flooring internally at four industrial facilities, including one freezer area. These applications differed from typical warehousing requirements, and seamless flooring was well suited in each instance.”
Acceptance of inherent superficial cracking
“Whenever we have recommended the seamless pavement option for an industrial construction project, the cracking has been mostly as anticipated,” Grant said.
“What must be understood is that the fine cracks which become visible on areas of seamless pavement are an inherent feature of the design and construction, not a flaw. Once the aesthetic considerations are put into proper perspective, along with differences in cost, seamless pavement becomes acceptable as a good solution.”
“The end result is less maintenance for the facility owner and the tenant.”