Civil Engineering May 2021 | Vol 29 No 4

Civil Engineering May 2021 17 and damage to the embankment during construction. It took approximately 1 100 geocontainers to complete the structure along the two sections, which now also provide a place for beachgoers to sit and relax while admiring the view. The Covid-19 lockdown delayed construction by a month and work only began in May after the initial hard lock- down restrictions were lifted. Because of this delayed start, the team encountered the extreme July 2020 storm when the revetment was only partially complete. It is estimated that this was the third-largest storm in the area since 1979. Amazingly, the only damage was that one of the containers at the bottom of the revetment pulled out by 10 cm. Both the design engineer and contractor were surprised, and very relieved, considering that the structure was at its most vulnerable, having been only partially constructed. After careful assessment, it was decided not to restore the moved geocon- tainer to its original position, as it had already settled and stabilised. However, all containers will be monitored and their position surveyed to detect any further movement. If required, portions of the revetment can be repacked in the future. LONG-TERM PLANS Further studies and area profiling are required to determine the most feasible long-term solution for the area. Some of the coastal protection structures considered for the interim solution may be feasible in the long run. However, all options have significant constraints and implications, both technical and financial. The City will therefore need to decide whether a costly “hard” structure should be built, or if the “softer” solution, which is capital-light but high-maintenance, would be more feasible.  REFERENCES Dassanayake DT, Oumeraci H. 2012. Engineering Properties of Geotextile Sand Containers and Their Effect on Hydraulic Stability and Damage Development of Low-Crested / Submerged Structures. The International Journal of Ocean and Climate Systems . 2012;3(3):135–150. Oumeraci H, Hinz M, Bleck M, Kortenhaus A. Sand-filled Geotextile Containers for Shore Protection. Proceedings ‘Coastal Structures 2003’, Portland, Oregon, USA. Project team Client City of Cape Town (CCT) Design engineer Maria le Roux Pr Eng (CCT) Project & construction manager Pierre Roux (CCT) Contractor Allan Klaassen (Southern Oceaneering) Geocontainer supplier Kaytech Reliable and Cost Effective. PDI's Pile Driving Analyzer ® and the New GRLWEAP14 To learn more about the Pile Driving Analyzer (PDA) or GRLWEAP14, visit www.pile.com. Pile Driving Analyzer ® (PDA) • High strain dynamic load testing and pile driving monitoring system • Evaluates static soil resistance, pile integrity, pile stresses and hammer energy • Up to 16 channels of data acquisition available • Field-to-office data transmission with SiteLink ® technology • Available in cabled or wireless versions GRLWEAP14 • Simulates pile response to impact or vibratory hammer forces • Hammer and driving system selection with known piling, soil and capacity requirements • Determines pile driveability and estimates total driving time • Available in standard and offshore versions