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_____________________________________________________________________________________ AbstractThis paper contains a summary and evaluation of an experimental research project carried out at the ICITECH laboratories, Valencia, Spain. The project consisted of the construction of a full-scale building that included a process of shoring, clearing and striking (SCS). The experimental model was used as the basis for the development of a FE model, including an evolving calculation, with the objective of simulating the construction process used, as well as studying the evolution of concrete properties during the test. The FE model was verified with the results obtained from the experimental model. Two further FE models were then developed from the original model and were used to simulate the construction of the same building using two different construction processes: one involving shoring and striking (SS) and the other shoring, re-shoring and striking (SRS). Finally, the SCS was compared to the SS and SRS processes, respectively, and an analysis was made of the advantages and disadvantages of each one. The paper breaks new ground in that for the first time ever a comparative study is made of the three most frequently used shoring techniques.

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_____________________________________________________________________________________ AbstractThis paper describes a computer tool for calculating and validating loads on floor slabs and shores in the construction of multistorey buildings with in situ casting. Its chief novelty lies in its optimization unit, designed to produce appropriate and optimum construction processes, which was created by applying exact and heuristic methods: Random Walk (RW), Descent Local Search (DLS) and Simulated Annealing (SA). The system has shown that it can improve three of the most important aspects involved in construction: time, cost and safety. In some cases the optimal solutions were achieved while reducing up to 53% of the cost of the shoring system, in shorter construction time, and meeting all the usual requirements for the construction of this type of building.

This paper analyses the influence of temperature changes on load transmission between floor slabs and shores during the in situ casting of concrete slabs by the shoring-clearing-striking method. Therefore several experimental studies were carried out which measured both the internal temperature evolution of the slabs and the loads on the shores. With the results of these studies, a Finite Element Model (FEM) of an experimental structure was then developed. In both the FEM and the experimental studies the same behaviour was observed regarding changes in temperature. When temperatures rose, the loads on shores decreased, accompanied by a reduction in slab deflection. When temperatures dropped, the loads on the shores increased, accompanied by an increased slab deflection. In the experimental study, for a temperature increment of ±1ºC the load per surface unit on shores varied between 0.13 kN/m 2 and 0.34 kN/m 2 , which represents between 2% and 6% of the self-weight of the slabs. The main cause of these load variations appears to be the temperature gradient inside the floor slabs.

This paper presents the results of tests carried out during the construction of a block of flats with reinforced concrete slab floors in Madrid, Spain, using the shoring, clearing and striking process. Loads on shores were recorded during the different construction stages of floor slabs 1 to 6. The experimental results were used to analyse load transmission between slabs and shores during the construction of the building. The results of the analysis showed that slab-shore load transmission differed according to the position of the span analysed, and also that variations in the construction process had a significant effect on the expected loads. The paper includes the evolving calculation

This paper describes a simplified method of estimating maximum loads on shores during the construction of multistorey buildings with in situ casting. Calculating this maximum value is fundamental to establish the design load of the shores and thus avoid possible safety problems caused by selecting the wrong type of shore. The procedure was verified and showed a good fit with both the experimental measurements and finite-element method calculations. This simplified procedure will be useful to both researchers and practitioners, who have to deal with this problem in the course of their daily work. The proposal also represents an important technology transfer to the industry as it is in the form of a simplified tool that comes fairly close to the results obtained by complex calculation methods. Actually, the maximum load obtained from the simplified method is 20·72 kN, which is very close to the value 21·37 kN obtained from an advanced finite-element model.

When constructing reinforced concrete (RC) building structures, knowing the loads to which the shoring system will be subjected during the entire process is one of the key aspects for ensuring safety during the work. Although various simplified methods of estimating the load transmission between shores and slabs during construction have been proposed to date, none of these methods can estimate the loads on individual shores during the different construction phases. This paper proposes a calculation method that allows the loads on individual shores to be calculated for each construction phase without having to resort to the use of advanced software. The proposal was validated by comparison with the results obtained from two actual buildings under construction and represents a step forward in the construction of RC building structures, as it is the first method that offers the possibility of estimating the loads acting on each shore during all the construction phases.