Editor's date: 2020.3.25

Editing unit: guangzhou hengqiao offshore engineering co., LTD

1. Engineering design basis

(1) technical regulations for aluminum alloy footbridge (TCECS 471-2017);

(2) aluminum alloy structure design code (gb50429-2007);

(3) urban bridge design specification (cjj_11-2011);

(4) designed bridge deck load: 3.5kn /m2.

(5) other current standards and norms of the state, the ministry of communications and related industries.

2. General construction period

The production cycle is 25-30 days and the installation time is 5 days.

3. Bridge abutment structure requirements

The two ends of the fixed bridge need sufficient bearing capacity of concrete abutment, which is used for embedded aluminum alloy base. The bottom height of the aluminum alloy bridge is close to the structural height of the abutment.

4. Design service life

According to the urban bridge design specification (cjj_11-2011), it is a small bridge. The designed service life of the aluminum alloy bridge is 30 years, and it can be continued to be used with proper maintenance.

5. Calculation of structural design

The aluminum alloy bridge is located in guangzhou, with a crowd load of 3.5kn/m2 and a hollow structure, which is subject to less wind. In the structural calculation, only the constant weight of the bridge and the crowd load are calculated. The main calculation process adopts the international general mechanical analysis software SAP2000 for analysis and calculation.

Condition setting :(1) the main structure of the bridge is welded. F1 section is 150*150*12mm, 6061T6 aluminum alloy square tube. D1 section is 100*50*6mm, 6061T6 aluminum alloy square tube. The ASEC1 section is the bridge panel.

(2) according to the technical specification of aluminum alloy footbridge (TCECS 471-2017) and aluminum alloy structure design specification (gb50429-2007), the welding contact strength of aluminum alloy decreases after welding, and the value in table 4.3.4 is used as the aluminum alloy strength value of tensile, bending and compressive resistance 100N/mm2, shear resistance 60N/mm2, and the following material is created (6061-t6 welding).

(3) next, the modeling is simplified. The four legs are hinged, and the unit is kn.m.c, as shown in the following figure. According to the drawing, the dimensions of length and width, 23.6x2.85m, and height 1.3m were determined by modeling the center line of the square tube. The actual width of the pedestrian passage is 2.4m and the weight of the bridge panel is about 370N/m2. Loading in the model :(3.5+0.37) *2.4/2.85=3.26KN/m2.