Optimization of Temperature‐Control Measures for Concrete Structures: A Case Study of the Sluice Project

Abstract

Temperature control and crack prevention in sluice pier concrete is a key issue in the early design and construction period. Strong surface insulation may lead to cracks after formwork removal, while weak surface insulation may result in a high crack risk in the early age. e water-cooling measure may also cause severe cracks at a rapid cooling rate. erefore, the optimum temperature control scheme should be comparatively studied against the alternatives. In this paper, we investigate crack prevention in sluice pier concrete as a multiple-factor system optimization problem and investigate an optimization method for temperature-control measures using the uniform design method and a neural network model. e minimum ratios for the internal and surface points of the sluice pier concrete are taken as inputs, and the corresponding combinations of temperature-control parameters based on the uniform design method are taken as outputs. Combined with a sluice project, the optimization method for the temperaturecontrol measures is implemented. e analysis results show that internal pipe cooling combined with reasonable surface heat preservation measures should be employed, and a low concrete pouring temperature is more beneficial than a low cooling temperature and long duration for crack prevention in sluice pier concrete.

Formation of Temperature Cracks of Concrete in High-Rise Buildings and the Corresponding Measures

“…It can be seen from the concrete heat conduction equation 4that the temperature change of a specified concrete is related to time and internal heat production, that is to say, for equation 4FORMATION OF TEMPERATURE CRACKS OF CONCRETE IN HIGH-RISE BUILDINGS... which is used for describing the temperature variation of a specified concrete, it has two unknowns numbers, t and in Q . There are innumerable solutions satisfying equation 4from the mathematical point of view, but the special value solution is needed in practical application; hence it is necessary to add initial and boundary conditions [9] to equation (4).…”

“…Therefore, measures need to be taken to prevent it. Huang [4] regarded the prevention of pier concrete cracks as a multifactor system optimization problem and studied the optimization method of pier concrete temperature control measures using uniform design method and neural network model. He found that pier concrete should adopt inner tube cooling and adopt reasonable surface insulation measures and low concrete pouring temperature.…”

Improved Hybrid Model for Predicting Concrete Crack Openings Based on Chaos Theory

“…Such models usually include temperature component, hydraulic component, and aging component. Experiments demonstrate that temperature is crucial to control concrete deformation [2,3] and that variations in temperature are an important factor in determining the opening and closing of concrete cracks [4]. e temperature component is thus considerably sensitive to the temperature variations [1].…”

Effect of Hydration Heat Inhibitor on Thermal Stress of Hydraulic Structures with Different Thicknesses

“…For small water conservancy projects, it is difficult to use temperature control measures such as aggregate precooling and ice mixing to control the temperature of concrete pouring due to economic factors. For thin-walled and massive concrete structures such as hydraulic tunnel linings, aqueducts, and small sluice floors, due to the large temperature gradient inside the structure and the constraints of the foundation or surrounding rocks, large thermal stresses will be generated [10,11]. e thickness of the structure is thin, so it is not easy to lay cooling water pipes, and the cost of measures to limit the cracks in the steel bar is high [12].…”