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Faure Pier - Concrete
Robben Island, Western Cape
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Click to view large map Coordinates: | The timber pier was replaced — during the First World War - with a more substantial reinforced concrete structure. The concrete pier functioned as the entry point onto Robben Island up until the Murray’s Bay Harbour was constructed during the Second World War. Precise details regarding the design and the date of construction of the concrete pier have not yet been confirmed. However, close examination on site, detailed measurements of the existing structure and photographic documentation have assisted in developing the description that follows. The concrete pier would have been designed in Imperial Units and the Metric dimensions are in each case followed by Feet (‘) and Inch (“) equivalents. Layout and extent of concrete pier The concrete pier has an existing overall length (measured from a recent Google Earth aerial photograph) of approximately 148 metres (482’). The concrete pier was designed and constructed as a set of six standard pier sections, terminated by a more robust terminal section. The first pier section commences on a concrete abutment but otherwise is the same as the other five standard pier sections. The six standard pier sections — measured on the pier deck — are each 22,130 m long by 4,950 m wide (72’ x 16’ 3”). The terminal section of the pier has been significantly eroded by the action of the sea and is no longer accessible, but would appear to be approximately 15,2 m in length (50’). Standard Pier Section (Sections 1 to 6) Each standard pier section was subdivided into three standard modules. Each of the three modules was set out on a regular structural grid of 7,160 mm (23’ 6”). The three standard modules were defined with four pairs of reinforced concrete columns, set out in two parallel rows and separated by a centre-to-centre distance of 2,750 mm (9’). The four pairs of concrete columns for each standard pier section each measured 460 mm by 460 mm (1’ 6” x 1’ 6”). Each pair of columns was provided with one diagonal concrete brace with a square cross-section of 300 mm x 300 mm (12” x 12”). The direction of each diagonal brace alternated at every column pair. The point of connection of the diagonal braces to the columns was made with an integral square concrete bracket. A construction joint was formed between each adjacent pier section and the end columns of a pier section were constructed up against the first columns of the following pier section, thereby forming two adjoining pairs of columns at each construction joint. Each parallel row of four columns supported a main longitudinal structural beam of reinforced concrete with a sectional dimension of 460 mm wide by 560 mm deep (1’ 6” x 1’ 10”) along the length of the pier section. The connection between each column to the main beam was detailed with a symmetrically splayed concrete bracket — except at the first and last columns. The soffit of the main beam was set at about 2,400 mm above sea level (at low tide). The pair of main beams in turn supported four primary transverse beams 460 mm wide by 380 mm deep (1’ 6” x 1’ 3”) spanning the width of the pier deck, with their centre-lines coinciding with the structural grid of the four column pairs below. Two secondary transverse beams 300 mm thick x 380 deep (1’ 0” x 1’ 3”) were inserted between each of the primary transverse beams. Each standard pier section therefore had a total of ten transverse beams (four primary and six secondary) spaced at regular 2,390 mm (7’ 10”) centres. The ten transverse beams were all half-lapped over the main structural beams with the upper face of the transverse beams 230 mm (9”) above the upper face of the main beam. Each of the ten transverse beams had tapered ends projecting beyond the line of the main beams and extending to the outer edges of the concrete pier deck which formed a cantilevered edge on both sides of the pier. The transverse beams supported the pier deck over their full length. The underside of the pier deck reduced in thickness on both sides by 50 mm (2”). On the North side the thickness reduced over a width of 1,190 mm (4’ 0”), on the South side by only 390 mm (1’ 3”). The reinforced concrete pier deck measured 150 mm (6”) in thickness at the edge and both exposed corners were provided with a broad chamfer. Terminal Section (Section 7) The concrete deck of the terminal section of the pier has been eroded away by the action of the sea and accurate measurement and documentation of this was therefore not possible. The terminal section has a different structural module at what appears to be closer centres. A narrow flight of stairs provided access down to the water’s edge on the North side. These stairs are clearly visible on a contemporary image of Prince Arthur (of) Connaught, the Governor-General of the Union of South Africa, leaving the Island after a visit, circa 1920. Derrick A derrick is a lifting mechanism typically comprising of a single mast articulated over a load by adjusting its supporting guys. A derrick is clearly visible on historic photographs at the terminal end of the pier. Witness marks on the concrete pier deck of hold down bolts around a circular baseplate confirm the position of the derrick mounted at the junction between Section 6 and the Terminal Section. Timber platforms Additional timber platforms were installed at some stage on either side of the pier adjacent to the derrick, presumably to provide additional staging areas for the loading and offloading of goods. Heavy timber baulks were inserted into the gap between the pier deck and the main structural beams — directly adjacent to the transverse beams — which provided the structural support for the timber planking of the loading platforms. All that remains of these timber platforms are the eroded timber baulks. Small scale building on pier A small square plastered brick structure with a flat concrete roof was constructed on the North side of the pier on the West end of the terminal section. It is possible that the structure housed pumping equipment to pump freshwater — delivered from a boat from the mainland — up to the water reservoir but this has not been confirmed. An alternative possibility is that the structure housed a stationary engine to power the lifting mechanism of the derrick. Surface finish The rusty remnants of the Robben Island mule trolley rails — which would have run the length of the pier deck — are visible at the abutment end on the Section 1 pier deck. A tarred road surface exists in areas on the pier deck. It is likely that the tar is a later surface finish and this layer obscures the fixing marks of the mule trolley rails. Balustrade The edges of the pier deck were protected with a robust balustrade. This balustrade was formed with freestanding balustrade posts connected by a set of three horizontal steel pipes. The positions of the balustrade posts for the first six sections coincided with the centre line of each of the transverse beams below the deck. A pair of posts occurred at the interface between each pier section. The edge of the pier deck and each bracketed end of the transverse beams was elaborated with facetted plastered projection below each balustrade posts. Most of the surviving balustrade posts are precast concrete balustrade posts with a typical height of 1,100 mm (3’ 8”). Some of the remaining posts are however of hardwood. It is perhaps not unlikely that the original balustrade posts were all in hardwood and subsequently replaced with concrete where required. Some of the better preserved precast concrete balustrade posts (on the South side of Section 3) confirm that the tops of the posts were segmentally rounded. The four corners of these balustrade posts were detailed with a broad chamfer — each terminating in a stop chamfer about 100 mm (4”) from the bottom. The plan dimensions of the concrete balustrade posts vary; those on the gridlines of the four primary column grids (and primary transverse beams) were 152 mm x 152 mm (6” x 6”) measured in plan. The intermediate balustrade posts measured 152 mm x 100 mm (6” x 4”) and these were placed coincident with the secondary transverse beams. The balustrade posts were cast with high strength concrete with three circular apertures to support the three 50 mm (2”) diameter horizontal metal balustrade pipes. A recess was provided in the concrete pier deck at each balustrade post for installation of the balustrade after the pier deck had been cast. The majority of the concrete balustrade posts are no longer extant The metal pipe components of the remaining balustrade sections are all badly corroded. Windmill platform A freestanding square reinforced concrete platform was constructed on the North side of the concrete pier. A contemporary photograph confirms that a standard steel framed Agricultural windmill was installed on the platform. The windmill was presumably used to pump freshwater — delivered from a boat from the mainland — up to the reservoir on the Island. The platform was placed coincident with the second and third balustrade posts on the north side of Section 4, with the platform level slightly below the level of the pier deck. The date of construction has not been determined but it is likely to have been concurrent with the construction of the concrete pier. The support structure for the windmill platform comprised of four inclined concrete legs with a set of horizontal beams a short distance below the platform. The top surface of the platform has a centrally placed circular aperture. Witness marks of steel fixing brackets are visible on each of the four corners of the platform. Brine outfall A modern 100 mm diameter plastic pipeline has been installed on the North side of the pier deck as a brine outfall from the Island's desalination plant — which pipe discharges into the sea at the end of the pier. The pipe line was laid between a parallel row of shingle concrete blocks and the pipe covered with a weak concrete infill. Statement of Significance The existing concrete pier is a significant early example of a reinforced concrete structure. Long term exposure of the concrete pier to sea water has resulted in corrosion of the steel reinforcing and consequent spalling of the concrete structure — nevertheless the concrete pier remains a well known landmark and historical marker on the Robben Island coastline. The concrete pier is associated with a significant period of the Island’s history, the final years of the Leper Colony, and as such deserves preservation. The concrete pier has also become a significant roosting place for sea-birds. References: Fish James W. Robben Island - the Home of the Leper. An Account of Thirty-Four Years' Gospel Work Amongst Lepers of South Africa. Published by John Ritchie, Kilmarnock, Scotland, 1924. pp 210 + 9 William MARTINSON, Osmond Lange Architects, February 2020 References:
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