Essential projects that meet your hight standards
Hardstanding road and pavement construction ensuring vehicle loads are supported, drainage design to effectively discharge rainwater; these are just some examples of the varying routes our infrastructure design services can take our engineers. These projects are often complex, with the need to consider significant use and environmental stresses to ensure they remain safe and operational for decades to come.
To execute these effectively, efficiency is our key driver, with a team that coordinates closely with contractors, engineers and local authorities to ensure your development is completed on time and within budget. In addition to being hands on during the implementation phase, we can also provide construction details for civil engineering elements such as kerbs, retaining walls, and steps, another way you can utilise the skill and expertise of the Chartered team at Richard Herrmann Associates Ltd.
Infrastructure for the future
With experience across a wide range of infrastructure projects, we bring the technical expertise and project management skills needed to deliver on time and to the highest standards. Our goal is to create infrastructure that not only serves today’s needs but also anticipates the demands of tomorrow. This includes incorporating sustainability into our planning stages, which is increasingly critical as communities look to reduce their environmental impact. From reducing carbon emissions during construction to integrating renewable energy sources, we are committed to delivering infrastructure that supports environmental goals.
Sustainable drainage solutions
Our drainage design will follow the SuDS sustainable drainage principles, where rainwater is attenuated on site, before being allowed to infiltrate into the ground. When serving hardstanding, drainage is also often cleaned through an interceptor initially. By working closely with your teams to understand the end goal, we’ll consider these processes and look to more sustainable ways to obtain the same results, mimicking natural drainage techniques wherever possible.
37
Years Est.
6,500+
Clients
100+
Years' Experience
Surpassing your expectations
Case Study: Repair and Protection of Corroded Embedded Steel Columns in a Bus Station
A bus station was found to have vertical cracking in the brickwork, which was causing concern for the safety and long-term stability of the structure. Upon investigation, it was determined that the cracking was due to the corrosive expansion of embedded steel columns, which had been a critical support element for the station. This case study explores the approach taken to diagnose the issue, implement repairs, and ensure the durability of the structure through the protection of these columns.
Project Background
The bus station in question is an important piece of local infrastructure, serving as a hub for public transportation in the area. However, over time, the station had developed significant structural issues. The primary cause of these issues was identified as the corrosion of steel columns embedded within the brickwork, which had led to the expansion of the steel and caused vertical cracking in the surrounding masonry.
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Key issues included:
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Vertical Cracking in Brickwork: Cracking was most noticeable in areas where the steel columns were embedded in the brickwork, compromising both the structural integrity and the aesthetic appearance of the station’s façade.
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Corrosion of Steel Columns: The embedded steel columns had begun to corrode over time, leading to their expansion, which put pressure on the surrounding brickwork. The resulting cracks were not just a cosmetic concern but a structural hazard if left unaddressed.
Inspection and Diagnosis
A thorough site investigation was carried out to assess the extent of the damage and the root cause of the cracking:
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Corrosion Assessment:
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Embedded Steel Columns: The steel columns embedded within the brickwork were inspected, and it was confirmed that corrosive expansion was the primary cause of the cracking. The corrosion was likely due to the combination of moisture, oxidation, and lack of adequate protection over time.
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Cracking Pattern Analysis: The vertical cracks in the brickwork were aligned with the locations of the embedded columns, confirming that the corrosion-induced expansion was responsible for the movement in the masonry.
2. Condition of the Brickwork:​
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The brickwork around the affected areas was found to be damaged but not entirely compromised. The cracks were localised to the areas around the columns, with the structural integrity of the masonry remaining largely intact.
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The damage was deemed to be repairable, provided the underlying cause—the corroded columns—was addressed.
Repair Scheme Development
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The repair scheme focused on restoring the structural integrity of the bus station by addressing the corrosion of the steel columns and ensuring that the surrounding brickwork was properly restored. The key components of the remedial works included:
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1. Exposure of Corroded Columns
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Column Access: The first step in the repair process was to carefully expose the affected steel columns by removing the surrounding brickwork where necessary.
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Cleaning and Inspection: Once exposed, the steel columns were thoroughly inspected to assess the level of corrosion. They were cleaned to remove all corrosion, dirt, and debris, revealing the full extent of the damage and ensuring that the protective coatings would adhere properly.
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2. Application of Protective Coatings
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Corrosion Prevention: After the columns were cleaned, a durable protective coating was applied to the steel surfaces. The coating was specifically chosen to prevent further corrosion by providing a waterproof barrier that would shield the steel from environmental moisture and oxygen.
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Durability Considerations: The coatings selected were designed to withstand harsh environmental conditions, including high humidity and temperature fluctuations, ensuring the longevity of the steel columns. This step was crucial in preventing any future corrosion that could lead to further damage.​
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3. Restoration of Brickwork
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Repointing and Rebuilding: Once the columns were fully protected, the surrounding brickwork was carefully restored. Cracked bricks were replaced, and repointing was carried out to ensure the masonry was secure and visually consistent with the original structure.
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Structural Stability: The repairs were designed to provide long-term stability to the brickwork, preventing further movement caused by the corrosion of the embedded steel columns.
Challenges and Considerations
1. Working Around Existing Infrastructure
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The repair process had to be carefully executed while the bus station remained in use. This required strategic planning and coordination to minimize disruption to public services and ensure that repairs were carried out efficiently without compromising safety.
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Temporary barriers and signage were used to protect the work area from public interference and ensure safe access for repair crews.
2. Preservation of the Building’s Aesthetic
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Given that the bus station was an integral part of the local infrastructure, maintaining its aesthetic appeal was important. Careful attention was paid to restoring the brickwork to its original appearance, ensuring that the repairs were discreet and did not detract from the station’s visual integrity.
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3. Long-Term Durability and Maintenance
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In addition to addressing the immediate corrosion issues, the repair strategy considered the long-term durability of the bus station. Measures such as the application of high-quality protective coatings were designed to prolong the lifespan of the steel columns and reduce the need for future repairs.
Results and Impact
1. Restored Structural Integrity
The remedial works successfully addressed the underlying cause of the vertical cracking in the brickwork. By treating the corroded steel columns and ensuring their long-term protection, the overall structural integrity of the bus station was restored. The brickwork was also stabilised, and the building's safety was significantly improved.
2. Prevented Further Deterioration
With the protective coatings applied to the steel columns, the risk of future corrosion was significantly reduced. The solution not only repaired the damage but also prevented further deterioration, ensuring the bus station would remain in good condition for many years to come.
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3. Minimal Disruption to Service
The work was completed with minimal disruption to the bus station’s daily operations. The station continued to function as a vital part of the local transportation network, and the repairs were carried out efficiently, allowing for a swift return to normal service.
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4. Enhanced Aesthetic and Safety
The work was completed with minimal disruption to the bus station’s daily operations. The station continued to function as a vital part of the local transportation network, and the repairs were carried out efficiently, allowing for a swift return to normal service.
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Conclusion
This case study demonstrates the successful repair of a bus station that was suffering from the corrosion of embedded steel columns. Through careful investigation, targeted remedial work, and strategic planning, the project restored both the structural integrity and aesthetic value of the bus station. The use of protective coatings on the steel columns ensured long-term durability, while the restoration of the brickwork reinforced the station’s overall stability.
By addressing the root cause of the problem—the corrosion of embedded steel columns—the remedial works not only repaired the damage but also provided a sustainable solution that will extend the lifespan of the bus station for years to come.
Case Study: Surface Water Drainage Design for Housing Development
A critical aspect of sustainable development is ensuring effective surface water drainage, particularly in areas with restricted off-site flow capacity. This case study details the drainage design for a housing development, where surface water runoff had to be managed despite severe restrictions on flows off the site. The design process required a careful balance of flood management strategies, innovative engineering solutions, and a collaborative approach to meet the project’s drainage needs.
Project Background
The housing development, located in an area with restricted surface water flow capacity, presented significant challenges in managing storm water. As part of the project, a robust drainage system needed to be designed to handle increased runoff from new housing while preventing flooding and ensuring compliance with environmental regulations.
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The primary challenge was that the off-site flows were severely restricted, meaning that typical drainage solutions, such as connection to local sewers or watercourses, were either impractical or could exacerbate flooding downstream. Therefore, a more innovative and controlled solution was necessary.
Key requirements for the project included:
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Managing Surface Water Runoff: Ensuring that surface water from the development did not exceed existing capacity limits.
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Flood Exceedance Routes: Designing the system to handle situations where rainfall exceeded typical design conditions.
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Environmental Considerations: Minimizing environmental impacts while managing surface water effectively.
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Design Process and Considerations
1. Assessment of Existing Site Conditions
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A comprehensive assessment of the site topography and existing drainage infrastructure was carried out. The drainage solution had to account for the following site conditions:
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Restricted Off-Site Flow: Limited capacity to discharge water from the development due to local infrastructure and environmental constraints.
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Flood Risk: The site was located in an area prone to surface water flooding, particularly during heavy rainfall events.n.
2. Development of Flood Exceedance Strategy
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A key aspect of the design was ensuring that the drainage system could handle flood exceedance scenarios—conditions where the volume of rainfall exceeds the capacity of the designed drainage infrastructure. This required:
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Flood Exceedance Routes: Routes were carefully considered where excess water could safely overflow without damaging the development. These routes were designed to direct excess water away from critical infrastructure and residential areas.
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Emergency Overflow Systems: In areas where the drainage system might be overwhelmed, the design incorporated controlled overflow routes, ensuring that floodwater was directed safely and predictably.
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3. Selection of Drainage Components
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Given the challenges of managing water in a restricted flow environment, the drainage system incorporated a combination of pre-cast concrete culverts and bespoke in-situ reinforced concrete chambers. Key elements included:
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Pre-cast Concrete Culverts: Pre-cast culverts were chosen for their strength, durability, and speed of installation. These provided a reliable means of conveying surface water beneath roads and critical infrastructure. The pre-cast design also allowed for efficient handling of the high flow rates during storm events.
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Bespoke In-Situ Reinforced Concrete Chambers: Custom-designed reinforced concrete chambers were used at key points to facilitate water flow regulation, manage overflow, and provide maintenance access. These chambers were designed to handle local conditions and ensure long-term resilience in the system.​
Challenges and Innovative Solutions
1. Site Topography and Drainage Constraints
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The restricted off-site flow conditions meant that careful planning was required to ensure water from the housing development would not increase flood risk in surrounding areas. The design team used advanced hydrological modeling to predict water flow and determine the most effective route for excess water. This modeling allowed for the precise placement of culverts, chambers, and overflow routes to ensure that the drainage system performed optimally under both normal and extreme conditions.
2. Environmental Considerations
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As part of the project, there were environmental restrictions to consider, particularly regarding the potential for increased surface water runoff affecting downstream watercourses or causing erosion. The design team incorporated Sustainable Drainage Systems (SuDS) principles to:
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Control the rate of discharge: The drainage system was designed to ensure that stormwater was released at a rate consistent with pre-development conditions.
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Use of permeable surfaces: Wherever possible, permeable paving and green infrastructure, such as rain gardens and swales, were incorporated into the overall design to reduce runoff and promote natural infiltration.
3. Integration with Other Infrastructure
The drainage system had to integrate smoothly with existing utilities and infrastructure, including roads, electrical systems, and water supplies. The design process involved close collaboration with civil engineers, architects, and other stakeholders to ensure that the drainage system did not interfere with other aspects of the development.
Implementation and Construction
1. Construction of Culverts and Chambers
The construction of the pre-cast concrete culverts was carried out with minimal disruption to the site, and the reinforced concrete chambers were cast on-site according to the bespoke specifications. The team used modern construction techniques to ensure that both systems were installed efficiently and to the highest standards of durability and safety.
2. Coordination with Other Contractors
Given the complexity of the project, coordination with other contractors was essential. The drainage work was carried out in parallel with other infrastructure installations, such as road construction and utility services, ensuring that the drainage system was integrated seamlessly into the overall development.
Results and Impact
1. Efficient Management of Surface Water
The drainage system successfully manages surface water runoff from the housing development, ensuring that the flows do not exceed the capacity of the existing off-site infrastructure. The use of pre-cast concrete culverts and bespoke chambers enabled the design to effectively control the flow of water while maintaining the integrity of the surrounding environment.
2. Resilience in Flood Exceedance Conditions
The design allows for effective management of flood exceedance events, ensuring that the development remains safe even under extreme weather conditions. The flood exceedance routes provide a predictable overflow path, reducing the risk of flooding to residential properties and critical infrastructure.
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3. Long-Term Durability and Maintenance
The design allows for effective management of flood exceedance events, ensuring that the development remains safe even under extreme weather conditions. The flood exceedance routes provide a predictable overflow path, reducing the risk of flooding to residential properties and critical infrastructure.
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3. Sustainable Design Practices
By incorporating Sustainable Drainage Systems (SuDS) and focusing on reducing the environmental impact of the drainage system, the design helps to protect local watercourses and reduce the risk of downstream flooding and erosion.
Conclusion
The surface water drainage design for this housing development successfully addressed the challenges of restricted off-site flow and flood risk, delivering an efficient and sustainable drainage solution. By integrating innovative engineering practices, such as pre-cast concrete culverts and bespoke in-situ reinforced concrete chambers, the design ensures the long-term durability and resilience of the infrastructure.
This case study highlights the importance of thoughtful drainage design in urban development, emphasizing the need for careful planning, environmental sensitivity, and the integration of advanced engineering solutions to create functional, safe, and sustainable infrastructure.
Infrastructure that connects communities
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