QUESTION $2(20$ marks$)$

Design timber forms for a $14ft$ high wall which is to be poured at the rate of $5ft$ per hour, internally vibrated. Assume the mix is made with type $1$ cement with no pozzolans or admixtures and that the temperature at placing is $70F.$ The unit weight of concrete is $150$ pcf with a slump of $3\frac{1}{2}$ inches. The forms will have continuing reuse. Assume deflection is limited to $\frac{1}{360}$ of the span. Use $\frac{3}{4}$ inch plywood sheathing which is available in $4ftx8ft$ sheets. Use $2$ inches $x6$ inches timber studs and $2$ inches $x6$ inches double wales. Lumber is No$.2$ Douglas Fir$-$Larch. $4300lb$ coil ties are on hand.

$(20$ marks$)$

QUESTION $3(20$ marks$)$

a$.$ List six $(6)$ factors that should be considered in the selection of a suitable pile driving hammer.

$(5$ marks$)$

b$.$ The falling ram of a drop hammer used to drive a timber pile is $6,500lbs.$ The free$-$fall height during driving was $19$ inches, and the average penetration for the last eight blows was $0\mathrm{.}5$ inch per blow. What is the safe rated load?

$(5$ marks$)$

c$.$ A crawler tractor costs $$250,000,$ has an estimated salvage value of $$50,000,$ and has a $5$ year life. Find the annual depreciation and book value at the end of each year using the double$-$declining$-$balance method of depreciation.

$(5$ marks$)$

d$.$ Briefly describe the process of installing a shell pile.

$(3$ marks$)$

e$.$ How does a pile support its applied load?

$(2$ marks$)$