that see the tremendous amount of work that goes into their construction in this building project five hundred men of many crafts working at the same time on different parts of the work each building project is managed by a highly each compartment of the truck contains the right amount of gravel and sand for one batch the concrete for this wall will contain one part cement two parts sand and three parts rated r now the concrete poured down into a bucket that holds one cubic yard the crame easily lift the heavy bucket to the top of the retaining wall where the concrete is poured into the high frame teamwork is required at all times the concrete is poured and then three foot layers from the bottom to the top of the wall this work is done by a skilled and semiskilled cement work before the concrete and electric vibrator is used to compact the concrete into a solid mass yes writing the bucket looks risky but it's quick and makes the work much easier many trips are required to fill the large wall inspectors watch the work to see that everything is built according to the plans the reflection of the sun in the mirror and they build the inspector to see in the darkest corner when the sun is not joining uses a flashlight he is checking to be all the fastenings on the farms are secure if the form should burst out and spoil the shape of the wall the concrete would all have to be pulled out then the forms rebuilt this would be costly when the forms have been removed a concrete wall stands strong and firm ready to be cleaned i am smooth electricians erect a lamppost along the lower roadway and also along the road on the top of the retaining wall the base of the lamp post is bolted into the foundation and cemented into place ma'am pull the wires through the post and put a transformer in each call to bring the electric current down to the proper voltage all the  at the end of the wall is a huge underpass where steel workers are putting in place this new reinforcing bar carrying these bars is heavy work as each bar is seventy feet long and weighs four hundred and fifty pounds it takes strong men to carry these ingles steel bars most of these men are experienced steel workers overseers and inspectors say that the steel bars are placed the proper distance from the poem and these bars are being placed on usually close together jones that this bridge is being built to carry a heavy load the steel carries the load and is held in place by the concrete indeed these men are getting there at the other side of the underpass a pile driver is driving the piles into place or the structure on which the concrete bridge will be built this man is adjusting the huge number which will pound the pole into place the cranes lift up the heavy hammer which falls on the ball and drives it into the ground until it is permanent to carry a twenty ton load engineers can measure accurately the resistance of a phone to a definite weight the operator of the pile driver operates his machine skillfully in another part of this road building project concrete workers are making curves and  are a concrete mixer on a truck called a transit mix is pouring concrete into the wooden forms a combination curb and gutter is made at one time men smooth out the concrete and when the concrete is hot enough the forms are removed next man smooth the base of the curb and finish it  crane driver and then hurried to help him they rush him to a hospital where he will receive first aid immediately but the work must go on our crane is pulled into place  mechanic to repair the damage but let's return to our road curves and governors are in place the ground is graded to a definite level to leave the required space for the concrete when it has been smoothed down sprinkled it is the second grip of the spreader finds the concrete much more level when this machine has tempted down fairly evenly the finishing machine takes over the work these machines have a system of rollers and trials to smooth off the concrete many different types of machines are used in a road building project