Superstructures concrete

Apparently a vault had been constructed around the superstructure of the furnace. It was 4.5 x 6 m in cross section and 4 m high. It was constructed of 20-cm-wide flange beams on 0.8 m (front) and 1 m (sides) centers faced on both sides with 10-mm steel plates and filled with dry sand. The explosion displaced the walls about 6 cm. The top of the vault which was supported by a 30-cm beam on top of a 20-cm beam was deflected about 8 cm. Steel doors mounted to slide in angle-iron tracks were blown off. A number of 1.9-cm bolts holding the door tracks were sheared cleanly. The furnace was driven down into the concrete floor and a penetration of some 10 cm was measured. 

American Concrete Institute (ACI) ACI 548.IR-92 Guide for the Use of Polymers in Concrete (1992) ACI 548.4 Standard Specification for Latex-Modified Concrete (LMC) Overiays(1992) ACI 546.1 R Guide for Repair of Concrete Bridge Superstructures (1980) ACI 503.5R Guide for the Selection of Polymer Adhesives with Concrete (1992)... 

Conventional reinforced concrete bridges refer to those with superstructures made of reinforced concrete. In general, prestressed concrete and steel bridges will have... 

Placing a protuberance such as concrete bock or steel bracket at superstructure or substructure as shown in Fig. 7(b). 

Sohanghpurwala, A.A. (2005). Manual On Service Life of Corrosion Damaged Reinforced Concrete Bridge Superstructure Elements. NCHRP 18-06A Final Manual. 

A shallow foundation is foundation built near or at ground (soil) or rock surface. This foundation is placed on firm soil near the ground and beneath the lowest part of the superstructure. Examples of these foundations are pad footing and spread footing. Deep foundation on the other hand is foundation that transmits structural loads to deeper soils or rock layers that are far from the surface. This foundation is constructed on a soil that is not firm, and transmits the load of the structure considerably below the ground of the lowest part of the superstructure. Deep foundations can be divided into two categories, that is pile foundation and drilled pier foundation or caisson. Piles are normally columns made of concrete, wood, plastic or steel that are driven into the ground. Drilled pier or caisson on the other hand is a special pile made of cast in situ concrete inside a bored or drilled hole. 

Concerning the serviceability requirements, the concrete bridges are classified in CSN 73 6222 (2008) into six categories B to G taking into accoimt the type of bridge superstructure and remaining working life as indicated in Table 1. 

It is assumed that the bridge is loaded by the self-weight of the superstructure, the permanent and traffic loads. The traffic load model LMl is considered which consists of the double-axle concentrated load gk (the tandem system TS, two lanes loaded by the axle loads 300 kN and 200 kN with the adjustment factor uq = 0,8), and the uniformly distributed load a qiciUDL, the first lane qi = 9 kN/m with adjustment factor Ug = 0,8, other lanes = 2,5 kN/m with factor a i = 1). The concrete class C 40/50 and... 

Adhesives may be used to bond precast concrete slab units directly to the flanges of longitudinal steel girders in bridge construction. Such a technique has been successfully employed in Germany(12). On one bridge described in Chapter 7, epoxy resins were used in a variety of forms and locations on the superstructure. The successful use of resins in this example suggests considerable scope for other applications. 

ACT Committee 546. Guide for repair of concrete bridge superstructures, Report No. ACI546. IR-80, Concrete International, September 1980, pp. 69-88. 

Piles are made of wood, concrete, and metal and are generally pushed or driven into the ground in order to support the superstructures both statically and dynamically, such as buildings and bridges. Recently, prefabricated or cast-in concrete piles are employed for supporting the superstructures. 

The contractor was operating a backboe when an employee attempted to walk between the swinging superstructure of the backboe and a concrete wall. As the employee approached the backboe from the operator s blind side, the superstructure hit the victim crushing him against the wall. 

The finite element models used in this study have combined both elastic-plastic solid elements, used for soils, and elastic and elastic-plastic structural elements, used for concrete piles, piers, beams and superstructure. In this section described are material and finite element models used for both soil and structural components. In addition to that, described is the methodology used for seismic force application and staged construction of the model. 

In this, second stage, number of changes to the model happen. First, soil elements where piles will be placed are removed (excavated), then concrete piles (beam-colnmn elements) are placed in the holes (while appropriately connecting strnctnral and solids degrees of freedom, as described above), columns are placed on top of piles and finally the superstructure is placed on top of columns. All of this constrnction is done at once. With all the components in place, the self weight analysis of the piles-colnmns-superstructure system is performed. 

Thanks to a large experience on the Insulation Market with a chromium oxide cast in place solution, Saint-Gobain SEFPRO is now proposing some unique AZS and high alumina concrete solutions for tank walls, superstructure walls and forehearth repairs. Both compositions exhibit particular good mechanical, glass and vapor contact behaviors for the different furnace areas. 

Hammerhead piers, as shown in Figure 2.5b, are often found in urban areas where space limitation is a concern. They are used to support steel girder or precast prestressed concrete girder superstructures. They are esthetically appealing and generally occupy less space, thereby providing more room for the trafhc underneath. Standards for the use of hammerhead piers are often maintained by individual transportation department. 

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