Problem 1: Determine the flexural strength of a W 410 x 67 beam with a simple span of 8 m and Fy = 250 MPa subject to the following conditions. 1. Lateral bracing are provided at 1.6 m interval along the span. 2. Lateral bracing is provided only at midspan. 3. No lateral bracing is provided. Properties of W 410 x 67 A = 8,580 mm² d = 409 mm bf = 179 mm tf = 14.4 mm tw = 8.76 mm Ix = 244 x 106 mm4 1,190 x 10³ mm³ Sx rx = 169 mm ly=13.7 x 106 mm4 Sy = 153 x 10³ mm³ ry = 39.9 mm J = 1.05 x 106 mmª Zx = 1,348 x 10³ mm³ Cb = 1.30

b) Dewatering is a term to describe the removal of groundwater or surface water from for example a construction site. In construction the water is pumped from wells or sumps to temporarily lower the groundwater levels, to allow excavation in dry and stable conditions below natural groundwater level. Discuss the following types of dewatering methods normally employed during construction of a building project: I. Open sumps and ditches  II.    Well point systems  III.   Deep well drainage