increasing function of the plastic moment capacity of its posts。 In general for the stiffness configurations that were addressed, it was found that the response of a ROPS to the applied vertical and longitudinal loading was approximately linear。 Based on this study, it is recommended that two post ROPS be carefully proportioned to form plastic hinges at the top and base of each post for the lateral loading sequence whilst possessing sufficient capacity to withstand the subsequent vertical and longitudinal loading phases。 In general it can be concluded that the simplified collapse load approach is an adequate design method for the assessment and proportioning of ROPS members provided that the estimated collapse load is at least equivalent to the minimum provision of the standard。

References

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Comments to Editor:

We have considered all the comments of the two reviewers and have carried out the necessary corrections。

In particular we have clearly stated the focus of the paper in section 1, last paragraph and made sure that the flow of the paper is compatible with this。 This is briefly discussed below:

The focus of the paper was to establish the feasibility of using FE techniques for (i) design and evaluation of ROPS and (ii) investigating the influence of parameters for enhancing ROPS performance。 Limited experimental testing is required, both to capture physical behaviour and to use the results to validate the finite elements models, which could then be used in further investigation。 As it is difficult to carry out full scale testing on ROPS, ½ scale models were designed based on the principles of similitude modelling and Buckingham’s Pi theorem was used to develop the relationships between the prototype and the model。 This paper treats ROPS models for a K275 bulldozer using experimental testing of a ½ scale ROPS model and extensive computer simulations first on ½ scale and then full scale FE ROPS models。 The FE analysis was validated through comparison of results for the ½ scale models and then extended to full scale ROPS models through similitude verification。 This project aims to (i) enhance our understanding on ROPS behaviour, (ii) improve energy absorption and safety and (iii) generate research information which will contribute towards the development of analytical techniques for design and evaluation that may lessen the need for destructive full scale testing。