# Compression at an Angle to Grain

## Safe Dimensions of the Notch at a Joint of a Timber Truss

**Situation**

The truss shown in is made from timber Guijo 100 mm × 150 mm. The load on the truss is 20 kN. Neglect friction.

Compression parallel to grain = 11 MPa

Compression perpendicular to grain = 5 MPa

Shear parallel to grain = 1 MPa

1. Determine the minimum value of *x* in mm.

A. 180 | C. 160 |

B. 150 | D. 140 |

2. Determine the minimum value of *y* in mm.

A. 34.9 | C. 13.2 |

B. 26.8 | D. 19.5 |

3. Calculate the axial stress of member *AC* in MPa.

A. 1.26 | C. 1.57 |

B. 1.62 | D. 1.75 |