ROCK ROLL MATTRESS INSTALLATIONS

PROJECT BRIEF	Used as a temporary scour protection measure, our brief was to install a series of rock rolls to form a rock roll mattress that was capable of resisting high velocities and shear stress loads of up to 1200 k/N which equates to around 120 ton-force within a high energy river. This system was temporary but it provided a suitable instant and flexible solution where other bioengineering techniques would be less effective. The rolls were moved into position via an excavator and secured to the abutment structure with galvanised chain shackled to shield anchors with forged eyes.
RESPONSIBILITIES	Project Manager for all subsurface works including the creation of the dive management system, risk assessment strategies and methodology process.
CLIENT	MMC Diving Services \| Dyer and Butler Construction Ltd
CHALLENGES	Initial challenges involved the movement of each rock roll across a fast flowing river in full flood. Thereafter challenges included the fixing of multiple units to the pier and abutment structures using hydraulic machinery and linking each roll to each other. Strict protocol required us to work in accordance with environmental guidelines and land owner approval throughout demanding conditions.
RISK RATING	High Risk
OUTCOME	Project completed

Skills : Bio Engineering, Civil Engineering, Commercial Diving, HSEQ, Hydraulic Drilling Equipment, Logistical Planning, Project Management