Surface Drainage Works
Transcrição
Surface Drainage Works
Surface Drainage Works Protection of Culverts and Low-level Crossings In tro d u ctio n 1 Structures built from double twist hexagonal wire mesh gabions and Reno mattresses are a valid and effective technical solution in the design and maintenance of culverts and low-level river crossings. (See tables for specifications). 2 In inlet works it is necessary to guide the flows into the culvert, thus avoiding dangerous uncontained flows. Furthermore, in restoration work one should be aware of erosion of river beds and banks, which may undermine the structure. In the case of deeply cut watercourses it is advisable to create structures capable of both containment and support. 3 When the river bed is not well defined it is good practice to extend the wing walls of the culverts to protect the flanks. At low-level river crossings, where the water flows directly over the roadway, protection is needed both upstream and downstream to prevent erosion which would immediately affect the roadway itself and render it unusable. 4 Structures made from gabions and Reno mattresses poses many technical and economic advantages over other possible systems, such as rip rap, cement or concrete. PROPERTIES OF WIRE Diameter Tolerance Zinc Coating mm mm g/m2 2.2 ±0.08 245 2.5 2.7 ±0.08 ±0.08 260 275 3.0 ±0.1 275 3.4 ±0.1 275 3.9 ±0.1 290 4.4 ±0.1 290 PROPERTIES OF MESH Mesh Type 60 80 b b (mm) Tolerance (%) Nominal External Wire Diameter (mm) Mesh PVC Galv. 2.2 3.2 2.7 3.7 60 -2 +5 80 -2 +5 MESH TOLERANCE The tolerance on the opening of mesh “b” being the distance between the axis of two consecutive twists according to SANS 1580:2001, EN 10223-3, EN 10218-2, ASTM A975. Tolerances and dimensions of the double twist mesh and PVC coated wire are covered by the local and international specifications which may differ from country to country. LOCAL AND INTERNATIONAL SPECIFICATIONS South Africa SANS 675:1993 European EN 10223-3 Zinc Coating SANS 675:1993 EN 10244-2 PVC Coating SANS 1580:2001 Mesh Specifications SANS 1580:2001 EN 10245-2 EN 10223-3 EN 10218-2 Wire Specifications American ASTM A975 ASTM A975 ASTM A641 ASTM A975 These advantages include: • simplicity and ease of installation even on sites with difficult access; • ease of finding suitable fill materials locally; • ease of construction even in arid locations; • unskilled labour can be used; • flexibility; • reduction of the thickness of filter layers; • ease of maintenance. The following types will be discussed: - Circular culverts. - Polycentric and pipe arch culverts. - Reinforced concrete box culverts. - Low-level river crossings (sometimes termed Irish crossings, fords or causeways). ASTM A975 5 A Without restriction of the section. With restriction of the section. A Culvert. Water course section. 1 2 2 Bueiro. Seção do curso d’ádua. a b c d, e Absence of lateral scour. Lateral scour. Scour at the end of wing walls. Correct solution. a b c d,e Ausência de atrito lateral. Atrito lateral. Atrito ao final das alas. Solução correta. A B 1 B A B From: Handbook of steel drainage and highway products. (American Iron and Steel Drainage) 2 1 Sem restrição da seção. Com restrição da seção. Sans rétrécissement de section. Avec rétrécissement de section. 2 Buse. Section courante. a b c d, e Absence d’érosion latérale. Erosions latérales. Erosions à l’extrémité des murs d’aile. Solution optimale. 1. 2. 3. 4. 5. a Circular culvert. Polycentric and pipe arch culvert. Reinforced concrete box culvert. Low-level river crossing. Influence of wing walls at the outlet section. 1 2 I nt r odu ç ã o In tro d u ctio n Estruturas construídas com gabiões e colchões Reno em malha hexagonal de dupla torção, são uma solução técnica válida e efetiva para projetos e manutenção de bueiros e passagens molhadas. (Ver tabela normas) Les structures en gabions et matelas Reno fabriquée de grillage à maille hexagonale double torsion, représentent une solution correcte et efficace pour le calcul et l’entretien des buses et des traversées inondables. (Voir table pour les specifications). Em algumas obras é necessário direcionar a água para o bueiro e v i t a n d o d a n o s g e ra d o s p o r f l u x o s n ã o c o n t r o l a d o s. Dans les ouvrages d’embouchure, il faut canaliser de façon sûre dans des buses les débits d’eau qui arrivent, afin d’éviter de dangereux contournements des ouvrages. Além disso, em obras de restauração deve-se estar atento às erosões do leito do rio e margens, que podem solapar a estrutura. No caso de obras que alterem drasticamente o curso d'água é aconselhável o uso de estruturas que desenvolvam várias funções, tais como: contenção, controle de erosão, revestimento, etc. Par ailleurs, dans les restitutions, il faut se méfier de l’érosion sur le fond du lit et sur les berges qui, en régressant, risquent de constituer un danger pour les structures. Quando o leito do rio não é bem definido costuma-se prolongar as alas dos bueiros para proteger as margens. Dans le cas des cours d’eau particulièrement encaissés, on conseille des structures capables d’offrir aussi bien une action de retenue et de soutènement. Para uma passagem molhada, na qual a água flui diretamente sobre a rodovia, se faz necessário proteções a montante e a jusante para prevenir eventuais erosões que afetariam a própria estrada, inutilizando-a. Lorsque le lit d’un cours d’eau n’est pas déterminé de façon certaine, il faut prolonger latéralement la protection le long du pied du remblai, jusqu’aux conduits souterrains, pour éviter un écoulement incontrôlé le long du remblai. Estruturas feitas com gabiões e colchões Reno possuem muitas vantagens técnicas e econômicas se comparadas a outros sistemas construtivos, tais como rip-rap, ou concreto. Dans les traversées inondables, enfin, où l’eau passe directement sur la chaussée, il est nécessaire d’avoir des protections en amont et en aval du plan de la route, pour empêcher l’érosion qui s’attaquerait immédiatement à l’assise de la route même et la rendrait impraticable. Estas vantagens incluem: • simplicidade de instalação e construção, até mesmo em locais de difícil acesso; • possibilidade da utilização de materiais locais para enchimento; • não exige mão de obra qualificada; • flexibilidade; • redução da espessura das camadas de filtração; • fácil manutenção. Les ouvrages en gabions et matelas Reno démontrent une série d’avantages techniques et économiques par rapport à d’autres systèmes d’enrochement, perré maçonné ou ouvrages en béton préfabriqué. Os tipos seguintes serão discutidos: - Bueiro circulares. - Bueiros policêntricos. - B u e i r o s r e t a n g u l a r e s e m c o n c r e t o a r m a d o. - Passagens molhadas. Ces avantages sont: • facilité de trouver sur site un matériau de remplissage adéquat; • facilité de réalisation, même dans les environnements arides; • utilisation de main d’oeuvre non spécialisée; • flexibilité; • réduction de l’épaisseur des couches filtrantes; • possibilité d’effectuer un entretien simple. On examinera les types d’ouvrages suivants: - Buses circulaires; - Buses à plusieurs centres; - Buses emboitées en béton armé; - Traversées inondables. B b c d e 1 2 2 1 1 1 2 2 3 Circ ula r Culve rts Circular culverts with D < 1.0m Buses circulaires avec D < 1.0m Bueiros circulares com D < 1.0m Variable 4 1.0m 3 1.0m Longitudinal section 0.5m 1.0m D 0.23-0.3m 1.0m 2.0m 1 1.0m 2 1.0m 2.0m 1.0m L L > 2.5-3 D 4.0m 5 4 Inlet 3 2.0m Outlet 4.0m 1.0m 2.0m 4.0m 2.0m 6 Culverts in braided river beds Bueiros em confluência de leitos de rio Buses circulaires pour lits peu profonds Outlet 1. 0m 0.5m 1.0m 0m 2. 6. 0m 0.23-0.3m 7 1. 2. 3. 4. 5. 4 Pipeline. Base layer. Gabion and mattress protection. Gabion key. AG Geotextile. 1. 2. 3. 4. 5. Oleoduto. Camada de base. Proteção em gabião e colchão. Gabião chave. AG Geotêxtil. 1. 2. 3. 4. 5. Buse. Couche de base. Protection en gabion et matelas. Gabion d’ancrage. AG Géotextile. Bu e i r o s Cir cular es Buses Circulair e s Bueiros circulares com D >1.0m Circular culverts with D >1.0m Buses circulaires avec D > 1.0m Longitudinal section Variable 3 4 A B Variable 3.0m D 1.0m 0.23-0.3m 1.0m A B 1 3.0m 2 1.0m 5 L L > 2.5-3 D 1.0m 3 Section A-A 1.0m Variable 2.0m 1.0m 1.0m 2.0m Variable Section B-B 1.0m 1.0m 5 0.23-0.3m Variable 2.0m 8 1.0m Variable Circular culverts with drop structures at the outlet section 2.0m Bueiros circulares com saída em degraus. Variable 3 Buses circulaires avec des escaliers à la restitution 6 Longitudinal section Variable 4 1.0m D 1.0m 1.0m 0.23-0.3m 1 1.0m 2 3.0m 5 1.0m 3.0m 2.0m 3.0m 3.0-5.0m 9 1. 2. 3. 4. 5. 6. Pipeline. Base layer. Gabion key. Gabion protection. AG Geotextile. Concrete capping. 1. 2. 3. 4. 5. 6. Oleoduto. Camada de base. Gabião chave. Proteção em gabião. AG Geotêxtil. Revestimento em concreto. 1. 2. 3. 4. 5. 6. Buse. Couche de base. Gabion d’ancrage. Défense en gabions. AG Géotextile. Couverture en béton. 5 6 10 11 12 13 14 15 10. Whale Rock, W. Cape, South Africa. 11. Sabi River Sun, Mpumalanga, South Africa. 12. Pretoria, South Africa. 13. Brazil. 14. Whale Rock, W. Cape, South Africa. 15. USA. 11 16 17 1 2 4 3 5 4.0m 18 2.0m 10.0m 2.0m 14.0m 1. 2. 3. 4. 5. Gabion structure. Woven mesh/geogrid reinforcement. AG Geotextile. Compacted earth back-filling. Crushed stone. 19 16. Lesotho. 17. Aliano, Matera, Italy. 18. Culvert through mechanically stabilised earth. 19 & 20. South Australia. 1. Estrutura em gabiões. 2. Reforço em malha hexagonal ou geogrelha tecida. 3. AG Geotêxtil. 4. Reaterro com solo compactado. 5. Pedra britada. 1. Structure en gabions. 2. Géotextile tissé/ géogrille de renfort. 3. AG Géotextile. 4. Remblai compacté. 5. Pierraille. 20 7 Polycentric and Pipe Arch Culverts Single polycentric culvert with head retaining wall Longitudinal section Variable 3 Variable 6 A 0.23-0.3m D 4 8 1 2 A 8 3.0m 1.0m 2.0m 2.0m L L > 2.5-3 D 6.0m 21 4 Single polycentric culvert with drop structure Longitudinal section Variable 6 3 7 9 0.23-0.3m Variable A 1.0m 0.23-0.3m D 4 8 1.0m 1 2 A 2.0m 6.0m 22 0.5m 8 3.0m 2.0m 2.0m 2.0m 4.0m 4.0m Multiple polycentric culvert with sloping head wall Longitudinal section Variable A 4 Variable 6 D 1.0-1.5m A 8 a 1 2 6.0m 5 23 0.23-0.3m 1.0m b 8 2.0m 8 2.0m 4.0m 1. 2. 3. 4. 5. 6. 7. 8. 9. Pipeline. Base layer. Head wall. Reno mattress lining. River bed key-in (a, b solutions). Upstream gabion key-in at banks. Key-in of drop structure. AG Geotextile. Concrete capping. 2.0m L L > 2.5-3 D Bue i ro Policênt r ico com e Tubo em Arco Buses à P lusie u r s Centre s Bueiro policêntrico com encabeçamento de muros de contenção Buse à plusieurs centres avec des murs de soutènement Section A-A 1 D 1.5-2 0.23-0.3m 2.0m Variable 2.0m Bueiro policêntrico com estrutura em degraus. Buse à plusieurs centres avec des ouvrages en gradins Section A-A 8 3 D 0.23-0.3m 7 m 6.0 1 1.5-2 0.5m 9 Variable 3.0m m 3.0 6.0m Bueiro policêntrico múltiplo com encabeçamento em taludes revestidos. Buse à plusieurs centres multiple avec revêtement de talus Section A-A 6 D 1 1.0m 1.5-2 0.23-0.3m 8 Variable 1. 2. 3. 4. 5. 6. 7. 8. 9. Oleoduto. Camada de base. Muro de encabeçamento. Canalização em colchão Reno. Leito de rio chave (a,b soluçãos). Margens a montante em gabião chave. Chave em estrutura em degraus. AG Geotêxtil. Revestimento em concreto. 2.0m Variable 1. 2. 3. 4. 5. 6. 7. 8. 9. Buse. Couche de base. Mur de soutènement. Revêtement en matelas Reno. Ancrage du lit du cours d’eau (solution a, b). Ancrage des gabions en amont sur les berges. Ancrage avec des ouvrages en gradins. 9 AG Géotextile. Couverture en béton. 24 25 24 & 25. La Lucia, KZN, South Africa. 26. Luanshya, Zambia. 27. Canada. 10 28. Swaziland. 26 27 28 11 Reinforced Concrete Box Culve rts Single box culverts in braided river beds Bueiro retangular em confluência de leito de rio. 3 Buses emboitées simples pour lits peu profonds Variable 1.5-2 1 Longitudinal section Variable 4 0.23-0.3m 0.23-0.3m D 5 1 2 1.0m 1.0m 3.0m 5 L L > 2.5-3 D Inlet 3 Outlet 4 D m 4.0 5 ble ia Var 5 2.0 3.0 2.0 m m 3.0 m L m 4.0 m 2.0 m 29 Box culverts with drop structures at the outlet section Bueiro retangular com saída em degraus. Buses emboitées avec des ouvrages en gradins Section B-B 4 1 A 1.0m 1.0m 1.0m 0.5m 3 Longitudinal section Variable 1.5-2 1 B 8 2.0m A 4.0m 5 2.0m 4 0.23-0.3m D 5 4.0m 1.0m 1 2 2.0m B 0.23-0.3m 1.0m 3.0m 30 12 3 1.0m 6.0m 1. 2. 3. 4. 5. 6. 7. 8. Box culvert in reinforced concrete. Reinforced concrete cut-off. Reno mattress lining. Gabion protection. AG Geotextile. Gabion key-in at bank. Reno mattress or gabion apron (0.23-0.3m). Concrete capping. 5 Bue i ro Ret angula r em Conc re to A r m ado. Buses Emboitées en Béton Armé Outlet section in mobile river beds Saída de bueiro com leito não revestido Restitution pour des lits non définis 7 m 1.0 D m 2.0 m 4.0 le riab Va m 2.0 L .0m 4 Outlet transition to the natural trapezoidal stream section Transição de saída para a seção trapezoidal natural Restitution avec raccordement à la section trapezoïdale courante 7 6 e abl i Var D L 2.0 m m 1.0 ble 6 ia Var Outlet transition to the natural stream Transição de saída para o fluxo natural Restitution avec raccordement à la section courante 7 6 D L 2.0 m m 1.0 m 6 4.0 ble ia Var m 4.0 31 1. 2 3. 4. 5. 6. 7. 8. Bueiro retangular em concreto armado. Barreira em concreto armado. Canalização em colchão Reno. Proteção em gabião. AG Geotêxtil. Gabião chave na margem. Apron em colchão Reno ou gabião (0.23-0.3m). Revestimento em concreto. 1. 2. 3. 4. 5. 6. 7. 8. Emboîtement en béton armé. Talon en béton armé. Revêtement en matelas Reno. Protection en gabions. AG Geotextile. Ancrage des gabions sur la berge. Renforcement en matelas Reno ou gabions (0.23-0.3m). Couverture en béton. 13 32 33 34 32. W. Cape, South Africa. 33. W. Cape, South Africa. 34. Dedza, Malawi. 14 18 35 36 37 35. Mississippi, USA. 36. Minnesota, USA. 37. Outeniqua Pass, W. Cape, South Africa. 15 Low-Leve l River Crossings Typical scheme Esquema típico Plan Schéma type 5 A 3.0-4.0m 3 6.0-8.0m Variable Road 3 A 5 5 Section A-A 0.23 - 0.3m 1 5 3 Alternative solution with a gabion curb 6.0 - 8.0m Solução alternativa com gabião freio 5 6 1 Alternative avec des rangées en gabions 5 6 8 4 2 0.23 - 0.3m 8 Variable 3.0 - 4.0m 38 3 4 2 0.23 - 0.3m 0.23 - 0.3m 1.0m 3.0 - 4.0m 1.0m Variable 6.0 - 8.0m 39 Reno mattress or gabion foundation for yielding soils 5 1 16 0.15 - 0.5m 3.0 - 4.0m 1. Road paving. 2. Sub-base. 3. Concrete cut-off. 4. Drainage hardcore. 5. Mattress protection. 6. Gabion curb. 6 2 5 7 0.23 - 0.3m 40 Matelas Reno en fondation ou gabions pour des terrains meubles Colchão Reno ou fundação em gabião para solos deformáveis 1.0m 7. Impermeable membrane. 8. AG Geotextile. 9. Concrete capping. 10. Pipeline. 11. Dry granular material. 12. Gabion retaining structure. 0.23 - 0.3m 8 Variable 1.0m 6.0 - 8.0m 1. 2. 3. 4. 5. 6. Estrada pavimentada. Base granular. Barreira em concreto. Núcleo drenante. Proteção em colchão. Gabião freio. Irish C ros si ngs Bue iros circ ula res Crossing with a drop structure Passagem molhada com estrutura em degraus. 5 Tra versée s Inondab l e s Traversée avec ressauts 1 9 8 2 0.23 - 0.3m 5 0.23 - 0.3m 1.0m 3.0 - 4.0m Variable 1.0m 6.0 - 8.0m 41 Culvert crossing with small discharges (causeway) Passagem molhada com descargas pequenas (calçada). Traversée avec buse pour des faibles débits Longitudinal section 10 12 Max level B 0.23-0.3m % Variable B 8 Variable Section B-B 1 12 11 1.0m 5 1.0m 0.23 - 0.3m 10 3.0 - 4.0m 2.0m 0.23 - 0.3m 8 Variable 2.0m 4.0 - 6.0m 42 7. 8. 9. 10. 11. 12. Membrana impermeável. AG Geotêxtil. Revestimento em concreto. Oleoduto. Material granular seco. Estrutura de contenção em gabião. 1. 2. 3. 4. 5. 6. Dallage. Couche de transition. Talon en béton armé. Structure filtrante. Protection en matelas. Rangées en gabion. 7. 8. 9. 10. 11. 12. Géomembrane imperméable. AG Geotextile. Couverture en béton. Buse. Matériau graveleux. Structure de rétention en gabions. 17 43 44 45 43 & 44. Richmond, KZN, South Africa. 45. Italy. 18 46 47 48 49 46. Paarl, W. Cape, South Africa. 47. Chapananga, Malawi 48 & 49. Papua, New Guinea. 19 ANY REPRODUCTION, INCLUDING PHOTOCOPY, FILM AND MICROFILM, IS FORBIDDEN. ALL RIGHTS RESERVED WORLDWIDE. Quality System Guarantees production, certified internal management and technical assistance in compliance with ISO 9001:2000 MACCAFERRI SA (PTY) LTD HEAD OFFICE - DURBAN, SOUTH AFRICA: P O Box 15777, Westmead, 3608 Tel: +27-31-700 8456 Fax: +27-31-700 8469 E-mail: [email protected] JOHANNESBURG, SOUTH AFRICA: P O Box 133, Kya Sands, 2163 Tel: +27-11-704 0160 Fax: +27-11-704 0159 E-mail: [email protected] MALAWI: P O Box 40494, Kanengo, Lilongwe 4, Malawi Cell: +265-8-842 503 Tel/Fax: +265-1-756 109 E-mail: [email protected] CAPE TOWN, SOUTH AFRICA: P O Box 22150, Fish Hoek, 7974 Tel: +27-21-702 1416 Fax: +27-21-702 2977 E-mail: [email protected] MADAGASCAR: BP 168, Antananarivo 101, Madagascar Tel: +261-20-22-231 02 Fax: +261-20-22-553 90 E-mail: [email protected] Website: www.maccaferri.co.za ZAF / CULVERTS : Eng - Rev. 01, Feb 2007 Maccaferri SA (Pty) Ltd, Durban, South Africa - Designed by: Wendy Potgieter - Printer: Pro-Print (Pty) Ltd.