300Ton All Terrain Crane Bridge Lifting Construction Case Study

300Ton All Terrain Crane Bridge Lifting Construction Case Study

1. Project Overview

Project Name: Expressway Precast Box Girder Lifting Project

Construction Equipment: XCMG XCT300G8-1 300-ton All Terrain Crane (dual-crane tandem operation)

Lifting Object: 25m precast concrete box girder, single weight 80 tons

Construction Features: narrow construction site, cross-road operation, high-precision synchronous lifting, long-radius positioning

Application Scenarios: highway bridges, municipal viaducts, large infrastructure projects

2. Project Background

The total length of the bridge construction section is 1.2 kilometers, containing 128 precast box girders in total. The original construction plan adopted a traditional bridge girder erecting machine. However, the construction area is surrounded by farmland and narrow rural roads, which leads to long assembly and disassembly cycles, high land acquisition costs and low construction efficiency.

After professional mechanical performance verification and construction scheme demonstration, the project department finally adopted the double 300-ton all-terrain crane synchronous lifting scheme. The new solution features flexible transition, no large-area temporary land occupation and short construction cycle. It effectively shortened the overall construction period by 30% and reduced comprehensive construction cost by 40%.

3. Pre-construction Preparation

3.1 Foundation and Site Treatment

The crane outrigger working area is filled and compacted with 50cm crushed stone, covered with 20mm thick steel plates to ensure uniform force diffusion. The ground bearing capacity is strictly tested to reach more than 18t/㎡. A special lifting warning area is set up with full closed isolation and professional safety personnel on duty to eliminate potential safety hazards.

3.2 Equipment Working Condition Configuration

The main boom is configured at 42m with a working radius of 28m, and the rated lifting capacity reaches 92 tons, which provides sufficient safety margin for 80-ton box girder operation. Each crane is equipped with 120 tons of standard counterweight, with fully extended outriggers and precise level calibration. High-strength steel wire ropes, professional balance beams and anti-drop safety hooks are adopted for lifting rigging to ensure stable stress of components.

3.3 Safety Technical Disclosure

All operators receive special lifting technical training and safety disclosure before construction. Unified operation commands are formulated for dual-crane synchronous lifting, rotating and landing. A 10-minute static trial lifting test is carried out before formal construction to check outrigger stability, rigging stress and component balance.

4. Standard Construction Process

1. The precast box girder is transported to the designated lifting position by flatbed truck and fixed stably.
2. Symmetric lifting points are adopted for binding, and the steel wire rope angle is controlled within a safe range to ensure horizontal stress of the box girder.
3. Perform no-load test operation of cranes to debug synchronous micro-motion control system.
4. Conduct trial lifting, lift the girder 20cm off the ground and hold for 10 minutes to confirm no abnormal conditions.
5. Two cranes lift synchronously, rotate steadily and transport the box girder to the top of the pier.
6. Fine adjust the position through traction ropes, and complete accurate positioning and slow landing.
7. After the component is stably installed and accepted, remove the rigging and complete the cyclic operation.

5. Equipment Performance and Construction Advantages

Stable Synchronous Lifting Performance: Equipped with intelligent anti-swing micro-motion control system, the crane realizes stable composite actions of lifting, rotating and luffing. The positioning accuracy is controlled within ±3cm, which meets the high-precision installation requirements of bridge components.

High Mobility and High Efficiency: The all-terrain chassis supports rapid transition. There is no need for long-time assembly and disassembly like traditional girder erecting machines. It can complete multiple-span girder installation every day, greatly improving construction progress.

Strong Site Adaptability: The telescopic boom system is flexible and efficient, adapting to narrow roads and complex terrain. It reduces temporary site construction and saves project investment.

High Safety Performance: Equipped with multiple safety protection devices such as overload protection, outrigger pressure monitoring and height limit, the whole machine maintains sufficient safety margin during heavy-load operation, ensuring long-term stable construction.

6. Safety Management Specifications

All lifting operations shall be stopped in case of strong wind above level 6, heavy rain and insufficient lighting. No personnel are allowed to stand under the lifting boom and cargo area. Regular inspection of steel wire ropes, hydraulic systems and outrigger foundation is required during construction. All lifting actions follow the principle of slow lifting, slow rotation and slow landing to avoid sudden acceleration and emergency stop.

7. Project Construction Achievements

The project successfully completed the installation of all 128 precast box girders in 28 days, which was 32 days ahead of the original schedule. The whole construction process achieved zero safety accidents and zero component damage. The dual-crane synchronous lifting scheme greatly reduced temporary engineering and equipment leasing costs, and was successfully promoted as a standard construction method for similar bridge projects.

8. Brief English Marketing Description

This case adopts two XCMG 300-ton all-terrain cranes for synchronous lifting of large precast bridge girders. With intelligent micro-motion control, stable heavy-load performance and flexible transition capability, the equipment efficiently completes high-precision bridge installation in complex and narrow construction sites, greatly shortening the construction period and reducing project cost. It is a reliable lifting solution for highway bridges, municipal viaducts and large infrastructure projects.