background infrastructure iron maintenance master metal pillar planning power processing progress rubble strong structure texture tough winch work worker working gear hard hardness beam brick building city column engineer equipment excavator foundation landscape sand scene strength works be-prepared to stop caution hazard readiness ready road-sign roadwork sign slow slow-down traffic warning workers workman workmen build child construction gravel hardwork jelly labour labourer labourers lady machine make mason smoke stones cement basis brasil brazil crane digging alarm alert ayto car combo deliver drive electric emergency engine light lighting orange signal small special transport vehicle wagon boots builders building construction cables chains construction site container helmeted helmets hoist hoisting hooks laborers lifting raising safety skip