BS 7533-101:2015 sets the framework for rigid pavement design in the UK, but applying it in Bournemouth requires local knowledge that goes beyond the code. The town sits on a mix of Branksome Sand, Parkstone Clay, and weathered Upper Chalk, creating a patchwork of bearing conditions across relatively short distances. When a pavement fails here, it is rarely the concrete quality that let it down. It is the ground beneath. Our laboratory processes core samples from across the conurbation weekly, and the variation in CBR values between a site near the seafront and one up toward Charminster can be striking. We combine in-situ permeability testing with laboratory strength analysis to feed accurate parameters into the pavement design model. A rigid pavement over soft alluvium near the River Stour behaves nothing like one founded on competent chalk. Getting the subgrade modulus right before a single bay is poured saves the client from expensive reconstruction later.
A rigid pavement in Bournemouth succeeds or fails in the first metre below the concrete. Chalk dissolution features and perched water tables are the hidden variables that standard desk studies miss.
Service characteristics in Bournemouth
Typical technical challenges in Bournemouth
Bournemouth's coastal climate introduces a risk that inland towns rarely face: salt-laden wind and spray accelerating corrosion in joint dowels and reinforcement. The seafront is an aggressive exposure class, and a rigid pavement here must be designed with adequate concrete cover and stainless steel components where necessary. Less visible but equally serious is the chalk beneath much of the borough. The Upper Chalk is susceptible to dissolution, forming solution features and small sinkholes that can create voids under a pavement. A rigid slab bridging a void will sound hollow and eventually punch through under repeated axle loads. Our risk assessments always include a review of historical geological maps and, where the chalk is shallow, a recommendation for seismic refraction to scan for anomalies before finalising the pavement design. Drainage is the other critical factor. A poorly drained rigid pavement on the clay-rich soils found in parts of Talbot Woods will suffer from pumping at the joints, eroding the subbase and leaving the slab unsupported at its edges. The design must integrate positive drainage from day one.
Our services
Our rigid pavement design service supports Bournemouth projects from preliminary assessment through to construction verification. We work directly for consulting engineers, local authorities, and contractors who need site-specific pavement designs backed by solid geotechnical data.
Subgrade evaluation for rigid pavement
We carry out plate load tests, dynamic cone penetration, and laboratory CBR testing on samples recovered from the formation level. The resulting modulus of subgrade reaction feeds directly into the Westergaard-based pavement thickness calculation, avoiding the conservatism of generic assumptions that inflate concrete volumes.
Full rigid pavement design package
From traffic loading classification to joint detailing and concrete specification, we produce a complete design package compliant with BS 7533 and the local Bournemouth ground conditions. The output includes slab thickness calculations, reinforcement schedules if required, and construction joint layouts.
Common questions
How much does a rigid pavement design cost for a Bournemouth project?
For a typical Bournemouth commercial or residential access road, our rigid pavement design package ranges from £1,690 to £4,870 depending on the extent of site investigation data already available and the traffic loading category. A design that requires new plate load testing and laboratory CBR work sits at the upper end of the range.
What is the difference between a flexible and a rigid pavement?
A rigid pavement distributes wheel loads through the flexural strength of a concrete slab, spreading stress over a wide area of subgrade. A flexible pavement relies on a layered system where each layer transmits load to the one below through grain-to-grain contact. Rigid pavements suit areas with weak subgrades or where settlement is a concern because the slab can bridge small soft spots.
How do you determine the right slab thickness for a rigid pavement?
We use the Westergaard method as adopted in BS 7533, which calculates slab thickness based on the concrete flexural strength, the modulus of subgrade reaction from plate load tests, the design traffic loading, and the expected number of load repetitions over the design life. Our laboratory determines the actual subgrade k-value rather than relying on estimated correlations.
Why is joint design so important for concrete pavements?
Joints control cracking, accommodate thermal expansion and contraction, and transfer loads between adjacent slabs. In Bournemouth's coastal environment, poorly designed joints lead to water ingress, subbase erosion, and eventual slab faulting. We specify contraction, expansion, and construction joint details including dowel diameter and spacing based on the slab thickness and expected traffic.
Does a rigid pavement need a subbase layer?
Yes. The subbase provides a stable working platform, protects the subgrade from frost action, and contributes to uniform support under the slab. We specify either cement-bound material or tightly graded granular subbase depending on the drainage conditions and the sensitivity of the underlying soil to moisture changes.