The urban road network system is the main carrier of urban traffic. The constraint factor that urban road network has on traffic leads to major urban traffic problems. In this paper, a questionnaire survey and the Delphi method are determined to determine the case cities with a population of 1-2 million at home and abroad. Literature research and comparative, analytical, and inductive research methods are used to compare, analyse, and evaluate the advantages and disadvantages of the road network structure of the case cities, to summarize the development law of the urban road network, and to propose a sustainable development structure model for each development stage of urban road network: the mode made of ring freeway + trunk street (the embryonic stage), the mode made of ring freeway + expressway + trunk street (the incubation stage), the mode made of outer ring freeway + outer ring expressway and radial expressway + trunk street (the mature stage). The innovative point of this paper is to put forward a sustainable development pattern for the road network structure of cities with a population of 1-2 million in China.
Rapid industrialization has brought both economic opportunities and infrastructure challenges to the people of Honduras, Central America. A 15 ha (37 acre) industrial park was recently developed south of the major Honduran city of San Pedro Sula, a rapidly growing municipality with a population of over 900,000 citizens. Workers commuting via public transit to the industrial park had no alternative but to make the hazardous crossing of a busy six-lane highway on foot. Construction of a two-span cable-stayed, precast, prestressed concrete bridge, in a very narrow right-of-way, provided a practical and beautiful solution for ensuring the safe passage of Buena Vista Industrial Park employees.
An all-precast/prestressed concrete system was used to build the new Olympic Stadium Project in San Pedro Sula, Honduras. Designed for the 1997 Central American Olympic Games, the stadium (mainly intended for soccer but can accommodate other sporting events) has a seating capacity of 40,000 together with 250 skyboxes. More than 7000 precast components were used which included single columns, A-frames, H-frames, primary beams, cantilever beams, single risers, double tees and skyboxes. This article presents the conceptual design, geometric layout, design features, load testing and erection highlights of the project. CONHSA-PAYHSA Group was responsible for the entire design and construction of the project.
Part 1 N o single event was more instru mental in launching the pre stressed and precast concrete in dustry in North America than the construction of the Walnut Lane Bridge in Philadelphia in 1950 (see articles in Sept.-Oct.1976 PCI JOURNAL 1 ).*More than anything else, how ever, it was the charisma, dy namism, and engineering talent displayed by the man who designed the Walnut Lane Bridge, namely Professor Gustave Magnel of Bel gium, that gave the impetus neces Whatsoever a man soweth, that shall he also reap (Galatians 6:7) sary for the acceptance and de velopment of prestressed concrete in the United States.On the other hand, very few know how this came about, how the Belgian-American Educational Foundation, an American-sponsored organization founded in 1920 as an aftermath of World War I, was to be instrumental in bringing Professor Magnel to the United States in 1946.Nor is it known how many appar ently unconnected events and coin cidences which took place during that period, led to the construction of the Walnut Lane Bridge.This is an extraordinary and fas cinating story which I believe should be recorded for posterity.'I gLL 0" a -,',i '-C--/.i2'-2i7Io 3,, ,,r,/.,I tLJ7, -4<))-,c L ,c, CSai 4' //o & fig.9. Portion of an original calculation sheet in Magnel's own handwriting.Prestressed Concrete in America L Colt, a consulting engineer in New York, had developed.as consultant to John A. Roebling & Sons company, a pre' stressed concrete box girder of variable depth for a Walnut Lane Bridge using cables made up of galvanized strands provided with sockets and swage terminal for anchorages, and bridge saddles over transverse ctlaptrragms, similar to the cables used in suspension bridges.
Located about 6 km southwest of San Pedro Sula, Honduras, the interchange bridge project, a 4-span, 1-way structure with an overall length of 65 m, proved challenging because of its sophisticated design. With its horizontal and vertical curves, the bridge is an aesthetically pleasing infrastructure project. This article describes the design of the prestressed, precast concrete hollow-core units used for the interchange bridge, which also includes a 5.5-m-wide travel lane and two 0.65-m-wide shoulders.
An all precast, prestressed concrete cable-stayed pedestrian bridge was constructed to transport workers across a busy four-lane highway to a major industrial park complex in San Pedro, Honduras. In designing the 30.8 m (101 ft) long structure, special attention was given to creating an aesthetic harmony between the bridge and the entrance canopy as well as the other buildings in the Bufalo Industrial Park. This article presents the design options, architectural concept, design considerations and particularly the design of connections, construction highlights, and especially the role that the nearly 150 precast concrete components played in erecting the bridge. It is concluded that the design concepts and construction method, which proved to be efficient and economically successful in Honduras, can be applied in other parts of the world.
This article describes the design and construction of a Honduran replacement bridge. The Megaplaza Interchange comprises two 131-foot-long (40 m) single-span bridges in an eastern suburb of San Pedro Sula, Honduras. The bridges are part of a north-south, secondary-circulating, main thoroughfare and were built to overpass a major roadway. The authors describe the use of precast, prestressed concrete girders to construct the bridges over the span. The design used precast concrete folded-plate abutments. These girders, made from 9000 psi (62 MPa) compressive strength concrete and each weighing 68 tons (62 Mg), require only a transport truck and two cranes for erection. The authors report on the girder geometry used, in which deformation and cracking are minimized. In addition, diaphragms, deck panels, curbs, and barriers were all made of precast concrete, significantly reducing time of construction. The article includes plans, drawings, and full-color photographs of the project.
To answer the question of whether the decorative craftsmanship of "Minnan-style" architecture has artistic value, the historical evolution of the decorative craftsmanship is examined in this study through three types of evidence: historical literature, historical images, and architectural history, thus inferring that the "Minnan-style" cresting art is divided into two major artistic features: the "Quanzhou style" and the "Chaozhou style," as well as the fusion of two crafts: "Porcelain-cutting Sculpture" and "Jiaozhi Pottery." The "Minnan-style" cresting originated from Quanzhou Port during the Song and Ming dynasties, which merged with the Chaozhou cresting style during the Kangxi period of the Qing Dynasty in the "Xianshui Temple, Taiwan County". The "Minnan-style" cresting art, which combines the ideas of ritual and music with inspiration from foreign art, was born from this.
46 Precast prestressed folded plate roof elements are cast flat with hinges between panels; they are transported flat, then opened to the desired angle during erection, with joints formed and cast in place to unify the structure. The construction method and design rationale, as developed in China, are being widely used in Honduras for both public buildings and industrial buildings. This paper describes the several such buildings recently constructed, and explains how waterproofing and ventilation are handled in the tropical climate.
The Texaco Wharf Maritime Port Facility is a major marine docking structure located off the northern coast of Honduras that has replaced a 1940s-era steel frame docking structure and access bridge. The structure comprises precast concrete piling and superstructure components that combine precast and cast-in-place concrete. The construction methodology almost completely eliminated the need for on-site formwork and proved to be very successful in producing a high quality docking project in a short time frame. This article presents the design parameters, construction challenges, and erection highlights of the project.
'/%3e%3cuse xlink:href='%23a' transform='rotate(23.036 .093 25.536)'/%3e%3cuse xlink:href='%23a' transform='rotate(45.87 1.273 16.18)'/%3e%3cuse xlink:href='%23a' transform='rotate(69.945 .996 12.078)'/%3e%3cuse xlink:href='%23a' transform='rotate(20.66 -19.689 31.932)'/%3e%3c/svg%3e)
