As part of the completed works, soil was carefully excavated to expose the existing retaining wall to the required depth for safe removal. Temporary earth supports were installed where necessary to ensure stability during the process, and the surrounding ground was fully reinstated once the works were finished.

The project also included the construction of a raised planter bed adjacent to the former retaining wall location, built in accordance with the engineer’s drawings. The result is a structurally sound and visually refined landscape feature that enhances both the functionality and appearance of the space.

Demolition of existing 250mm thick reinforced concrete suspended slab, cutting and disposing damaged area of slab, cut to locations as shown on engineers drawings (approx 7.60 x 4.50m)

Breaking out of existing 250mm thick reinforced concrete suspended slab to exposed retained reinforcement
perimeter of demolished slab, 2000mm C/L of column as shown on engineers drawings (approx 45m2)

E.O. for reducing 250mm thick retaining wall to expose reinforcement sufficient to lap new, allow 500mm depth across 6m

E.O. for reducing column heads to expose reinforcement sufficient to lap new in accordance engineers details (2 Nr)

Reinforcement, high yield, Type B500A, B500B or B500C Ribbed Bars to BS4449:2005, tied into existing, as detailed on engineers drawings and rebar schedule, new reinforcement to be installed with minimum lap as detailed (H16 min lap 800mm)

New suspended slab and column heads, tied into existing, H16 bars as reinforcement schedule and engineers drawings, approx 256 Nr (2.5t)

H12 U bars to head of retaining wall as reinforcement schedule and engineers drawings, approx 30 Nr (0.5t) – PROVISIONAL

CONCRETE REPAIRS

Preparation of surfaces

Removal of soot particles and damaged anti-carbonation surface coatings from existing surfaces by shot blasting (including the provision of all protections as necessary), ensure cement laitance and all surface contamination is removed back to a sound substrate, leave ready to receive new coatings

Soffit of upper slab level (approx 930m2)
columns 300 x 300 including head

Testing and Survey (as required within SIKA specification)

Percussion – Hammer test all concrete surfaces to identify loose or unsound concrete (including removal)
soffits of suspended slabs

Preparation of schedule of all defects and repairs required

Preparation of sketches indicating locations and position of defects, repairs, carbonation tests, cover meter survey depths to support testing and schedule of defects and repairs

Concrete repairs as detailed with the SIKA specification contained within the appendix to this document (Ref JC-00013184); including, Sika Monotop reinforcement protection and Sika Monotop 615 repair mortars

Note: provisional allowances included for tender pricing and comparison – rates to be used for adjustment of actual repairs identified on site.

Soffits of suspended slabs and columns

Core holes drilled in testing of concrete 70mm dia x 200mm deep (6 Nr)