Drumurile in lume

[b1]

Cowi wins contract for 8-lane immersed tunnel in Canada



Cowi has won an engineering contract to develop designs for a proposed eight-lane immersed tunnel in Vancouver, Canada.

The proposed tunnel will have three general purpose traffic lanes and one dedicated bus lane in each direction, as well as a bi-directional multi-use cycle path/pedestrian walkway to improve travel across the George Massey Crossing without restricting navigable space for marine traffic.

As part of its role, Cowi will provide the reference concepts and geotechnical underpinning for the ambitious CD$4.15bn (£2.41bn) river crossing.
Drawing on its experience designing the original George Massey tunnel in 1959, Cowi will oversee removal of the original four-lane tunnel and construction of its eight-lane replacement. Cowi will also be responsible for designing a flood control system around the new tunnel that can withstand extreme river flows as well as anticipated increased sea levels.

Cowi senior project director Darryl Matson said: "It's projects like these that light up the engineer inside each of us. We are very passionate about this project as it lies in the backyard of our local team – we use it frequently so we know what a difference we can make to the community. It's a key transportation link with engineering challenges such as minimising disruption to local ecosystems during construction and ensuring the final tunnel will stand up to natural disasters. It will both test and showcase our talented engineers."

He added: "The tunnel will break new ground with a dedicated pathway for cyclists and pedestrians and a dedicated bus lane alongside road traffic, helping create cleaner transport and bringing huge trade and travel benefits to the local communities."

Cowi has worked on the design of several immersed tunnels around the world, including the world's longest immersed tunnel for motorists in China and the first immersed tunnel designed against typhoon waves in South Korea.

Sursa.

[b1]

Longlang Expressway to be opened to traffic in Loudi City, HunanProvince andrural China:

The Longlang Expressway starts from Longtang Town, Lianyuan City, Hunan Province, and ends at Langtang Town, Xinhua County, Hunan Province. It connects the built Changshao Lou Expressway and Xinxu Expressway. The main line is about 74 kilometers long. Simultaneously build 13.015 kilometers of Meijiang connection line, Chetianjiang connection line and Xinhua connection line (set up Meijiang connection line 8.7 kilometers, Chetianjiang connection line 2.6 kilometers, Xinhua connection line 1.715 kilometers), adopt two-way four-lane expressway Standard, the design speed is 100 km/h, and 8 interchanges are set up in Longtang (junction), Lianyuan North, Anping, Chetianjiang, Wentang, Youxi Bridge, Meishan Longgong, Langtang (junction), and the total investment is estimated About 8.4 billion yuan.
Longlang Expressway is a provincial-level key project, an important part of the fourth horizontal of the "seven vertical and seven horizontal" expressway network in Hunan Province, and the horizontal connection line between the Erguang National Expressway and the Hubei National Expressway.
After the project is completed, Changsha City will reach Huaihua City via Changshao Lou Expressway, Xinxu Expressway, Xuhuai Expressway, Huaizhi Expressway and other expressways, which can save 70 kilometers of driving mileage compared with Shanghai-Kunming Expressway and Changtan West Expressway, which highlights the It acts as a transportation hub connecting the east and the west. It is of great significance to improve the expressway network in Hunan Province, improve the traffic in Lianyuan, Lengshuijiang and northern Xinhua, meet the growing demand for transportation, and promote regional economic development.

Large scale Interchange Bridge in Shijiazhai, Jishou, Western Hunan, China:

The interchange project between the Xiangxi section of the Hunan Province Baomao Expressway and the Shijiazhai hub of the Yongji (Yongshun County to Jishou City in the western Hunan Province) expressway is "recumbent" in the valley, like a musical note on the earth.

Zhejiang Zhoushan Jintang Bridge, China:

Jintang Bridge is a sea-crossing passage connecting Zhoushan City and Ningbo City in Zhejiang Province, China. It is located above the gray turtle ocean. It is one of the components of the Yongzhou Expressway (National Expressway G9211) and also the "Zhoushan Sea-Crossing Bridge". an important part of the project.
The Jintang Bridge starts from the Jiaochuan Junction Interchange in the west, crosses the Huiheyang sea area, and reaches the Jintang Island Interchange in the east; the total length of the line is 21.029 kilometers, and the cross-sea bridge is 18.415 kilometers long; the bridge deck is a two-way four-lane expressway, and the design speed 100 km/h.
The construction of Jintang Bridge started on September 30, 2005; the main bridge closing project was completed on June 25, 2008, and the entire bridge section was completed; it was opened to traffic on December 25, 2009.
The main navigation hole is arranged with a span of (77+218+620+218+77) meters, the full width of the box girder is 30.1 meters, the beam height at the center line is 3.0 meters, the total height of the cable tower is 204.0 meters, and the height above the bridge deck is about 152.362 meters; It is 6.5 meters thick, 56.78 meters long and 34.02 meters wide. The Donghang Kong Bridge is arranged with a span of (122+216+122) meters, the root beam is 13.3 meters high, the mid-span beam is 4.4 meters high, and the main pier is 8.8 meters high. The west navigation hole adopts (87+156+87) span arrangement, the height of the root beam is 9.25 meters, and the height of the mid-span beam is 3.4 meters.

[b1]

Tanzania revives stone arch bridge construction for river crossings

















It is common for residents of the Kigoma region in north west Tanzania to make dangerous crossings of rivers to reach workplaces, schools, hospitals and markets during the rainy season. But for many, such journeys will soon no longer be necessary as a result of a new bridge construction programme. Removing the inherent risks involved in crossing rivers could also bring global benefits.

Safe year-round river crossings are being delivered with the construction of 70 stone arch bridges, as part of Belgian development agency Enabel's Sustainable Agriculture Kigoma Region Project (SAKiRP). For this project, co-funded by the Belgian and Tanzanian governments, Enabel is working with Tanzanian rural and urban road agency Tarura, the regional branch of the ministry of agriculture and local communities.

The aim of the project, launched in 2016, is to upgrade agriculture value chains but it has also resulted in a new approach to bridge construction. "One of the interventions in the value chain is to improve the access to markets for smallholder farmers and that's where the bridges come in," says Enabel junior expert rural infrastructure Willem van der Voort.

In a country where reinforced concrete bridges are the most common form of river crossing, a decision to construct stone arch ones is unconventional. Enabel opted for this bridge type because of experience gained in Congo and Uganda in its previous incarnation as the Belgian Technical Cooperation. Projects in those countries showed that stone arch bridges are cost efficient, allowing for more to be built with available budgets. Tanzania's stone arch bridge construction programme started in early 2018 and already 44 have been completed. There has been no shortage of expertise among local engineers and craftsmen, thanks to a detailed construction manual compiled by Enabel.



The manual provides supervisors with an easy step by step guide to planning and construction processes. The stepwise approach aims to ensure adherence to quality requirements and construction methodology. It includes detailed design tables for semicircular and segmental arch bridges. The tables provide exact figures for parameters such as thickness of keystone, arch radius, thickness and abutment height as well as minimum foundation depths depending on the bridge span selected.

"Stone arch bridges were the mainstream technology [around the world] until the 1920s or so [...] These design tables are rooted in empirical evidence and, so far, we have very good experience with them," says Enabel's SAKiRP project manager Steven Hollevoet, whose knowledge in the field was instrumental in the creation of the manual. The longest bridge built for the project to date is 31m.

"The spans of single arches range from 1.5m to 8m for Roman – semi-circular – arches and from 3m to 10m for segmental arches," van der Voort explains. The capacity of each bridge is 40t, which is several times more than the requirements for rural roads in the country. An advantage of standardising the design of the bridges is that relatively little engineering input is required for each bridge. Senior lecturer at Brunel University London and project consultant Dr Adrienn Tomor adds that standardisation saves time and costs. Tomor was impressed with the detail of the design tables and when she checked them using relevant software she identified overdesign. She also found differences in the way these stone arch bridges are being constructed compared to their European equivalents.

Van der Voort explains: "We work with rough stone and relatively inexperienced masons, compared with those who built European bridges in the 17th to 19th centuries. To cope with the risk of imperfections in craftsmanship, our bridges are overdesigned."

Cost-efficiency:
Building stone arch bridges is very labour intensive and construction costs can be prohibitively expensive as a result. But the bridges built for this project are five times cheaper than equivalent concrete ones, says Pharles Ngeleja who is Tarura regional coordinator for the stone arch bridges in Kigoma region. Lower costs were achieved through the engagement of local communities and because of lower materials costs. Unlike government infrastructure projects, there are no contractors involved. Enabel provides surveying, design and supervision resources, while Tarura brings supervision and asset management of built structures. It also mobilises local communities. The communities that will benefit from a bridge provide volunteers to excavate foundation pits, gather sand and collect stones and pieces of wood. They also help with masonry work and raise money to contribute to the payment of labourers. Materials costs are minimised because a significant amount of the materials used are sourced in the area near the site. Enabel tops up some of these materials if required – sometimes it has to bring better quality sand from other parts of the country. It also provides cement.



Construction costs are further limited by reusing arch formwork which requires large amounts of timber, an expensive material in Tanzania. "You can reuse it between five and 10 times before it degrades too much. We have different sets of formwork for the spans that we most often have to build," van der Voort says. These solutions bring the cost of materials below those for reinforced concrete bridges of the same size, according to the project team. There are further cost savings because no heavy machinery is needed, according to Hollevoet.

The long lifespan of stone arch bridges makes comparative costs even lower. Van der Voort says that the stone arch bridges should last at least 100 years at a conservative estimate, claiming that they have a longer lifespan than concrete bridges built in the country. "The concrete bridges that are built here are often of lower quality than in Europe because of the way the concrete is poured, the quality of the aggregates, the mixing and so on. So their lifespan here is not very long." Hollevoet adds that stone arch bridges are not prone to the corrosion which affects the steel reinforcement in concrete bridges.

Construction process:
Once a site is selected and the preliminary survey –  which includes an assessment of hydrology, soil type and river bank condition – is carried out, those involved in the construction process are trained. Work often has to stop during the rainy season because of flooding so foundations are prepared during the dry season. In the meantime, a head mason trains craftsmen to construct the arch on timber formwork. Construction of the arches and the proper placement of the stones is the most challenging part of the process, Hollevoet says.



"In terms of management [the most challenging part] is quality control, making sure that the masons and labourers adhere to the minimum principles of good construction. And that means that all gaps are filled, there is a good bond, stones are washed, etcetera," he adds. The time needed to construct each bridge varies according to the span, weather conditions and time of year. During busy periods for the agriculture sector, there are fewer volunteers.

Even though constructing a stone arch bridge is more labour intensive than building a concrete one of the same size, Hollevoet says the stone arches take similar or even less time to build. He explains that concrete used in concrete bridges takes a month or longer to cure, while a week is enough for that used in stone bridges.

Global revival?
The SAKiRP bridge programme ends in June 2023 and construction of the 70th and final bridge started last December. Van der Voort says Enabel will soon make a decision about whether it will construct more bridges as part of the work to improve agriculture supply chains. More stone arch bridges may be constructed in the Kigoma region of Tanzania, even without Enabel's involvement. Ngeleja says Tarura's senior management team was impressed with the low construction costs and it is looking into using this technology in other parts of the country.

Hollevoet believes the project demonstrates that stone arch bridges are an ideal solution for developing countries with limited budgets looking to develop their road networks at district and village level. For more economically developed countries, he says that even though the cost advantage of stone bridges may be affected by higher labour costs, increased demand for these structures could originate from the drive to cut carbon emissions. He explains that carbon footprint of stone arch bridges is significantly lower than that of reinforced concrete bridges because less cement is used.

Tomor believes that materials costs for stone arch bridges can be similar to concrete bridges in developed countries if random rubble is used instead of cut stone, because the former is often disposed of by quarries and therefore can be bought at a relatively low price. "The other option is to use recycled stones," she adds.

Tomor has been a strong advocate for the construction of such bridges in the UK. She initiated a project to build one in Bristol, which in 2016 was granted the first planning permission for a stone arch bridge in the UK for more than 100 years. Ultimately the project did not proceed, but Tomor is now working on an application to build a stone arch bridge in Devon. She highlights the fact that there is no British standard for the design of stone structures, such as buildings and bridges. She is working on introducing stone design into the curriculum for civil engineering. "But for that you also need to create guidelines. It will take some time...that's why in the meantime is so important to provide standard designs," Tomor adds.

She is also planning to adopt what has been done in Tanzania and develop an international design guide. Tomor concludes: "This will enable people internationally, just to take the standard tables and build stone bridges. The capacity and material needs obviously will have to align with each country's standards."

Sursa.

[b1]

Longjiang Road-Changhong Road Interchange, China:


The Longjiang Road-Changhong Road Interchange is located in Changzhou city, Jiangsu province. The project of the interchange was officially started in August 2017, and it was fully opened to traffic on June 29, 2019.

[b1]

Baijusi Yangtze River Bridge, China:

[b1]

Winding Panlong Road with 639 haripin turns on westernmost border of China:

The Panlong Ancient Road is located in Waqia Township, Taxkorgan County (Taxian for short), Kashgar Prefecture, Xinjiang, on the westernmost border of China. This road is not for the faint of heart or anyone prone to motion sickness.

In fact, this road is called Wacha Highway瓦恰公路, which is one of the two roads leading to Wacha Township, Ta County. Although the road is difficult and dangerous, it can greatly shorten the distance and access time. Because this road is like a giant dragon lying on the mountain, it is named "盘龙古道 Panlong Ancient Road  (盘龙 means Circling Dragon in Chinese)".

The Huacha Highway is more than 70 kilometers long, of which the Panlong Ancient Road is about 30 kilometers long. The altitude ranges from 3,000 meters to more than 4,100 meters. The entire drop reaches more than 1,100 meters. Therefore, 639 curves appear on the 30 km mountain road, and they are basically s-bends of more than 180 degrees.

The Panlong Ancient Road is like a huge wandering dragon, hovering on the Pamir Plateau of about 4,100 meters. The dark asphalt road is perfectly combined with the colored mountains. Such a unique wonder attracts countless people to drive there to experience the special and adventurous journey on this road.

[b1]

Azi în Coreea de Sud se inaugurează o secțiune de 31,2 km. din Autostrada 400 (Metropolitan Second Circular Expressway sau în coreeană: 수도권제2순환고속도로) - a doua centură de autostradă a Seulului.

Există planuri ambițioase ca Autostrada 400 să formeze o șosea de centură regională în jurul Seulului, cu o lungime totală de 263 de kilometri. Întreaga autostradă ar trebui să fie gata până la jumătatea anului 2026. Construcția ei a început în mai 2005.


Powered by API/PUM imgur uploader

[b1]

The high-speed Qianhaizi Double Helix Bridge on the cloud in China:

Ganhaizi Bridge is located in Shimian County, Ya'an, Sichuan on the Ya (An) Lu (Gu) Expressway. It has a total length of 1811 meters, a bridge width of 24.5 meters, and a total of 36 spans. It is the longest steel tube truss girder highway bridge in the world. The main structure of the bridge is made of steel fiber concrete, which is the first case in the history of bridge construction in the world. Sichuan Province has the longest mileage, the largest investment, and has created many world records. So far, the Jingkun Expressway has been fully connected across the 1,045 kilometers in Sichuan Province.
After the completion of the Qianhaizi Bridge, it will drive on it as if it were in the "cloud". It was officially opened to traffic on April 28, 2012. The Jingkun Expressway, a national trunk expressway, realizes the full highway in Sichuan, shortening the distance from Chengdu to Xichang to 420 kilometers, and it can be reached by self-driving in 5 hours. This saves about half of the time compared to the past. The completed Xipan Expressway is enough, and the whole journey takes only 6 hours.
As the Ganhaizi Bridge has entered winter with low temperatures and the road surface is slippery and easy to accumulate snow, snow removal vehicles and other emergency rescue equipment will be equipped in the future. At the same time, the guardrails on both sides are 30 centimeters higher than ordinary high-speed guardrails to prevent vehicles from rushing out of the bridge. In addition, the piers of the bridge also adopted a unique air pipe design, which reduced the weight of the piers. The seismic intensity of the bridge was designed to be 9 degrees.

[b1]

Imagini din timpul construcției podului Lvzhijiang din China:

Distanța de la turn până la ancorajul montan este de 780 de metri, depășind precedentul record deținut de podul de autostradă Jinshajiang Hutiaoxia cu o deschidere de 766 de metri.

Locație:


Cum v-a arăta la finalul construcției:














Comparație cu podul Jinshajiang Hutiaoxia:



LE: Podul este aproape finalizat și va fi deschis traficului încurând:

Mai multe imagini din timpul construcției.

[b1]

Autostrada 700, Șoseaua de centură Daegu, Coreea de Sud:
31 martie 2022

Cele două segmente care cuprind Autostrada 700 din jurul Daegu, Coreea de Sud, au fost deschise traficului, cu o lungime totală de 32,9 kilometri. Acesta este un segment de vest de 20,3 km și un segment de nord-est de 12,6 km în jurul Daegu. Daegu este a treia zonă metropolitană ca mărime din Coreea de Sud, cu o populație de 2,5 milioane de locuitori. Lucrările la autostradă au început pe 10 martie 2014.

[b1]

Podul George Washington la sfârșitul anilor 1940:

[b1]

Un pic de istorie 9:Cum se făcea mentenanța drumurilor din SUA în trecut?

[b1]

Autostrada E1A (japoneză: 第二東名高速道路 - Shin Tōmei Kōsoku Dōro, română: Autostrada Shin-Tomei), Japonia:
16 aprilie 2022

Harta autostrăzii:


Un segment de 13 kilometri din autostrada E1A a fost deschis traficului în Japonia. Noul segment este situat între Isehara-Oyama IC și Hadano IC, aflându-se la vest de Greater Tokyo Area.

Locație capătul estic.
Locație capătul vestic.

LE: Acesta este al 700-lea mesaj al meu.

[b1]

World's first road-rail dual-purpose cable-stayed bridge with three cable planes, China:

The Wuhan Tianxingzhou Yangtze River Bridge is located on the Yangtze River waterway and is one of the components of Wuhan's Third Ring Road， connecting Qingshan District and Jiang'an District in Wuhan City, Hubei Province. On December 26, 2009, Tianxingzhou Yangtze River Bridge opened to traffic.

Tianxingzhou Yangtze River Bridge starts from Qinghua Interchange in the south, crosses the Yangtze River waterway, and ends at Hanshi Interchange in the north; the whole bridge is 4657.1 meters long and 27 meters wide; the upper floor of the bridge is a two-way six-lane expressway with a design speed of 60 km/h. The lower layer is a two-way four-track railway with a design speed of 200 km/h.

After the Tianxingzhou Yangtze River Bridge is opened to traffic, the Beijing-Guangzhou high-speed railway crossed the bridge and formed a railway loop with the Wuhan Yangtze River Bridge, doubled or tripled the capacity of the railway to cross the Yangtze River. At the same time, it has further improved the road network in Wuhan, relieved the shortage of traffic capacity of the first and second bridges of the Yangtze River in Wuhan, and laid a solid foundation for the further development of the city of Wuhan.

Jiaozi Overpass, China:

[b1]

Planuri de viitor în Turcia: 5527 km de autostradă construiți în perioada 2023-2035...