Calculate and dimension timber beams with lateral reinforcement according to Eurocode
Building in existing buildings implies the desire to preserve existing timber beams in the long term despite damage or changes in the use of the building. However, with the trend in the construction industry towards more sustainability, the demands on structural engineers are increasing. The FRILO Reinforced Timber Beam HTV+ program therefore helps to economically calculate and dimension timber beams with lateral reinforcement to ensure their preservation.
In modern structural design, building existing structures is becoming increasingly important. To ensure that the maintenance of existing timber structures is as economical and efficient as possible in the future, FRILO has brought the HTV+ Reinforced Timber Beam calculation program onto the market. The HTV+ enables structural engineers to calculate and dimension timber beams that need to be reinforced on one or both sides by additional timber cross-sections or steel sections. The lateral reinforcements are flexibly connected to the timber core using fasteners as a coupled system.
The individually configurable system input enables structural engineers to realistically depict the static system to be maintained in the HTV+ and to supplement the support with the required reinforcement measures. Among other things, users can variably define supports for the different static systems and enter loads individually. The calculation is carried out using a truss analysis in which the loadings are distributed to the cross-sections involved via the fasteners.
The system input in HTV+
In the HTV+ from FRILO, timber beams with any rectangular cross-section can be reinforced laterally with individual timber cross-sections or steel sections. Different types of timber or strengths can also be assigned to the rectangular timber reinforcements. If the lateral reinforcement is carried out using steel cross-sections, various channel and L section series are available to choose from. The special feature lies in the separate choice of static systems for the timber core and for the reinforcements. By completely freely defining the arrangement, storage and dimensions of each reinforcement, the program can map any static system.
The individual systems are coupled using freely selectable fasteners. In addition to the usual bolts, pins and threaded rods, connector joints are also available. Individual types, distances and other parameters can be specified for each fastener group. This means that every timber beam can be reinforced economically where the reinforcement is needed. In addition, structural engineers are able to define joints or cross-sectional jumps to depict cross-sectional failures or cross-sectional weakening in the timber core.
The load input in HTV+
In the HTV+ from FRILO, timber beams with any rectangular cross-section can be reinforced laterally with individual timber cross-sections or steel sections. Different types of timber or strengths can also be assigned to the rectangular timber reinforcements. If the lateral reinforcement is carried out using steel cross-sections, various channel and L section series are available to choose from. The special feature lies in the separate choice of static systems for the timber core and for the reinforcements. By completely freely defining the arrangement, storage and dimensions of each reinforcement, the program can map any static system.
The verification in HTV+
The calculation is based on a strut-and-tie model in which the timber beam is flexibly coupled to the reinforcements at the discrete locations via the fasteners. The action effect and deformation of the timber beam and the reinforcement can be precisely calculated in each section and in each connecting element. In this way, the defined support conditions and the real load application are also taken into account precisely.
This not only allows the necessary dimensions of the supports and reinforcements to be determined, but the connecting elements can also be used precisely where they are required by the load. Based on the resulting internal forces, all timber cross-sections and fasteners are verified according to Eurocode 5 and the steel sections according to Eurocode 3. In addition, the program determines the support pressure according to Eurocode 5 for each existing support of the timber core.
The interfaces to the HTV+
Thanks to the direct integration into the FRILO world, users can transfer timber beams that have already been entered and calculated in the Continuous Beam DLT+ (or HTM+) at the push of a button and then reinforce them. This saves structural engineers valuable time when making entries. In addition, the PLUS surface of the new HTV+ is closely aligned with the Continuous Beam. Users who have tried and tested the Continuous Beam can intuitively create the individual static systems and connect them using fasteners. The support reactions calculated in the new HTV+ program can also be transferred directly to all FRILO support programs. As an addition, the complete system can also be transferred to the in-house program Framework RSX.
