Intelligent Structure Jacking & Movement Technology
Extend the Service Life of Near-shore Facilities: A Solution to Resolve Settlement-induced Issues on Reclaimed Lands
Fortune Chen, PhD
CTCI Resources Engineering Inc

Petrochemicals plants are generally build near to the seashore or on the hydraulic reclaimed lands. Its adjacent facilities such as storage tanks , pipe racks, and buildings are also constructed either on piles or directly on soils on the reclaimed land. Thus 'Renovation' or 'Demolish & Rebuild' of the plants and its facilities is a matter of concern.

The paper describes on Structure Jacking Technology to renovate or demolish & rebuild of petrochemicals plants and its adjacent facilities in a cost- effective manner and to enhance their ser vice life for another decade.

Petrochemical plants have been set up away from urban areas in many countries to avoid the possible environmental impacts. Instead, they are usually built in the Industrial zones near seashore or on the hydraulic reclaimed lands. Facilities such as storage tanks, pipe racks, and buildings are constructed either on piles or directly on soils on there claimed land. Subsequently, the land naturally settles downwards as its own weight acting on the existing sea bed and results in the facilities suffering the settlement-induced problems during construction or in the later operation, i.e. facility tilts or structure angular distortion exceeding the allowable limits. The plant therefore faces a dilemma of 'Renovation' or 'Demolish & Rebuild' as it has no idea which choice will give a costeffective result.

Figure 1 :Structure stressanalysis for tank operation at designated high level

Case studies performed on storage tanks in Taiwan indicated that both the cost ratio and the time ratio of 'Renovation' to 'Demolish & Rebuild' roughly went to 1 to 3 subject to the local available resources. The renovation technology took use of structure jacking system together with a computer-controlled synchronous jacking module to precisely control hundreds of hydraulic jacks to renovate the tilted storage tanks or pipe racks successfully and ex tend their service life for another decade.

Figures 2 : FEM Simulation for optimized elevation curve and structure jacking stages/steps

Prior to performing the structure jacking, 3D-scanning and FEMs tress analysis/ simulations on the deformed tank are done to check the existing stress distribution and to determine the optimized elevation curves for the next renovation procedure(see Figures 1-2). The struc ture jacking system integrates the conventional hydraulic jacks with the advanced computerized system to control solenoid valves and wireless displacement transducers, so that the hundred jacks will be able to push the structure simultaneously with designated movements (see Figures 3-4). It resolves the settlement -induced problems and extends the service life of huge oil storage tanks, multi-layer pipe racks, shop buildings, etc.

Figures 3 : Renovation of storage tank by using intelligent structure jacking system

Figures 4 : Ex tend Pipe Rack service life by using computerized jacking system

Figures 5 : Pushdown Caisson using ground anchors and computerized jacking system

In addition, the same technology is also applied in historical buildings relocation and pushdown caisson construction (see Figure 5). This structure jacking technology provides an intelligent solution to perform the 'Upward, Downward and Horizontal movement' and satisfy various demands in engineering and construction.